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Artificial Sweeteners | The Paleo Diet

Introduction: Evolutionary Perspective

It’s pretty clear that if we follow the example of our hunter gatherer ancestors, artificial sweeteners should not be part of contemporary Stone Age diets. In my book, The Paleo Diet Revised (2010)1 I warned against drinking artificially sweetened soft drinks and further strengthened my opposition to all artificial sweeteners in 2012 with The Paleo Answer.2 Over the past few years numerous epidemiological (population), animal, tissue and human studies have demonstrated the adverse health effects of these synthetic chemicals. A particularly powerful study just published in the October 2014 issue of Nature3 provides a convincing argument against the use of artificial sweeteners in our food supply. If you consume artificial sweeteners in the form of sodas or foods once in a blue moon, they will have little or no adverse effects upon your long term health. However, I would never recommend that you drink artificially sweetened beverages or foods on a daily or even weekly basis, as they may promote insulin resistance,3, 4 obesity in adults5-7, 30-33 and children,8-11, 32, 44 metabolic syndrome diseases,12-18, 33 migraine headaches,19-23 adverse pregnancy outcomes,24-26 childhood allergies,24 and certain cancers.27-29

Artificial Sweeteners

The table* below shows the five artificial sweeteners that the U.S. Food and Drug Administration (FDA) has approved for consumption.

Artificial Sweeteners: Agents of Insulin Resistance, Obesity and Disease | The Paleo Diet

*Note that the artificial sweetener cyclamate was banned in the U.S. in 1969, but is still available in certain countries outside of the U.S.

In addition to these artificial sweeteners, the FDA has sanctioned a sugar substitute, stevia, as a dietary supplement since 1995. Stevia is a crystalline substance made from the leaves of a plant native to central and South America and is 100 to 300 times sweeter than table sugar. A concentrated derivative of stevia leaves called rebaudioside A was recently (2008) authorized by the FDA and goes by the trade names of Only Sweet, PureVia, Reb-A, Rebiana, SweetLeaf, and Truvia.

Since 1980 the number of people consuming artificially sweetened products in the U.S. has more than doubled.32, 33 Today, at least 46 million Americans regularly ingest foods sweetened by these chemicals – mainly in the form of soft drinks, or in a huge number of artificially sweetened products, including baby food.32, 33

Artificial Sweeteners and Obesity

If you were to ask most people why they drink artificially sweetened beverages, the resounding answer would be to enjoy a sweet drink without all the drawbacks of sugar laden sodas. Doesn’t everyone know that soft drinks sweetened with sugar promote obesity, type 2 diabetes and the Metabolic Syndrome (high blood pressure, high blood cholesterol and heart disease)? Of course, and the standard line of thought goes something like this, “if we remove refined sugars from our diets and replace them with artificial sweeteners, we would all be a lot healthier.” I can agree with the first and last parts of this argument, but not the second.

A number of large epidemiological studies5-7; 8-11, 44 and animal experiments34-43 indicate that artificially sweetened beverages may actually not be part of the solution to the U.S. obesity epidemic, but rather may be part of the problem.30-33 Unexpectedly, a series of large population based studies, including the San Antonio Heart Study6 examining 3,682 adults over a 7-8 year period; the American Cancer Society Study7 including 78,694 women; and the Nurses’ Health Study5 of 31,940 women have clearly demonstrated strong associations between increased intakes of artificial sweeteners and obesity. Alarmingly, these effects have been observed in children8, 11, 44 as well as in adults, and were utterly unanticipated because most artificial sweeteners were previously thought to be inert and not react with our gut or metabolism in an unsafe manner.30-33, 45

Laboratory Animal Experiments

In the course of the past few years, animal experiments have reversed these erroneous assumptions. Rats allowed to eat their normal chow consumed more food and gained more weight when artificial sweeteners were added to their diet.34-43 The best available evidence indicates that artificial sweeteners when consumed by either laboratory animals or humans promote weight gain by altering the normal gut bacterial biome3, 45 which in turn adversely affects glucose and insulin metabolism and consequently appetite. Who would have ever thought that a mass marketed product which supposedly was designed to help us lose weight may have actually caused exactly the opposite result? But wait, there is more.

Cancer

In 1958 the federal government deemed both saccharin and cyclamate as “generally recognized as safe (GRAS)” artificial sweeteners. Eleven years later the FDA banned cyclamate and announced its intention to ban saccharin in 1977 because of worries over increased cancer risks from both of these chemicals. Consumer protests eventually led to a moratorium from congress on the ban for saccharin, but unfortunately it is still with us today. Aspartame was sanctioned for use as a sweetener by the FDA in 1996, followed by sucralose (1999), neotame (2002), and acesulfame (2003). You may think that anytime chemical additives such as artificial sweeteners were permitted into our food supply, they would have been thoroughly tested and conclusively shown to be safe. Unfortunately, this is not always the case, and the potential toxicity of some of these sweetening compounds are widely disputed in the scientific community, particularly in light of newer, more carefully controlled animal studies.27-29

A series of more recent experiments29 from Dr. Soffritti’s laboratory in Bologna, Italy have shown that even low doses of aspartame given to rats over the course of their lives leads to increased cancer rates. This study is important, because many people may consume much higher concentrations of this chemical by drinking artificially sweetened beverages on a daily basis for years and years.

Migraines

Aspartame has also been shown to trigger migraine headaches in certain people because it breaks down into a compound called methanol (otherwise known as wood alcohol) in our bodies. And it’s not just aspartame that may prove dangerous to our health when we ingest these synthetic concoctions on a regular basis. Recent animal experiments27 have revealed that saccharin, acesulfame as well as aspartame caused DNA damage in mice bone marrow. Frequently, it is difficult to translate results from animal experiments into, meaningful recommendations for humans, because large epidemiological studies generally don’t show artificial sweeteners to be risk factors for cancer. Does this mean that these compounds are completely safe? Absolutely not.

Pregnancy

A 2010 prospective study25 of 59,334 pregnant women from Denmark showed for the first time that consumption of artificially sweetened soft drinks significantly increased the risk for pre-term delivery (less than 37 weeks). This condition shouldn’t be taken lightly, as it represents the leading cause of infant death. An interesting outcome of this study was that only artificially sweetened beverages increased the risk for pre-term delivery – and not sugar sweetened soft drinks. A follow-up study confirmed these results.26 Am I recommending that pregnant women consume sugary soft drinks? Emphatically no! But these studies indicate that sugar sweetened drinks may be less harmful to your developing fetus than are artificially sweetened soft drinks.

Cordially,

Loren Cordain, Ph.D., Professor Emeritus

REFERENCES

1. Cordain L. The Paleo Diet. John Wiley & Sons, NY New York, 2010.

2. Cordain L. The Paleo Answer. John Wiley & Sons, NY New York, 2012

3. Suez J, Korem T, Zeevi D, Zilberman-Schapira G, Thaiss CA, Maza O, Israeli D, Zmora N, Gilad S, Weinberger A, Kuperman Y, Harmelin A, Kolodkin-Gal I, Shapiro H, Halpern Z, Segal E, Elinav E. Artificial sweeteners induce glucose intolerance by altering the gut microbiota. Nature. 2014 Oct 9;514(7521):181-6

4. Horwitz DL, McLane M, Kobe P. Response to single dose of aspartame or saccharin by NIDDM patients. Diabetes Care. 1988 Mar;11(3):230-4.

5. Colditz GA, Willett WC, Stampfer MJ, London SJ, Segal MR, Speizer FE. Patterns of weight change and their relation to diet in a cohort of healthy women. Am J Clin Nutr. 1990 Jun;51(6):1100-5

6. Fowler SP, Williams K, Resendez RG, Hunt KJ, Hazuda HP, Stern MP. Fueling the obesity epidemic? Artificially sweetened beverage use and long-term weight gain. Obesity (Silver Spring). 2008 Aug;16(8):1894-900.

7. Stellman SD, Garfinkel L. Artificial sweetener use and one-year weight change among women. Prev Med. 1986 Mar;15(2):195-202.

8. Blum JW, Jacobsen DJ, Donnelly JE. Beverage consumption patterns in elementary school aged children across a two-year period. J Am Coll Nutr. 2005 Apr;24(2):93-8.

9. Forshee RA, Storey ML. Total beverage consumption and beverage choices among children and adolescents. Int J Food Sci Nutr. 2003 Jul;54(4):297-307

10. Striegel-Moore RH, Thompson D, Affenito SG, Franko DL, Obarzanek E, Barton BA, Schreiber GB, Daniels SR, Schmidt M, Crawford PB. Correlates of beverage intake in adolescent girls: the National Heart, Lung, and Blood Institute Growth and Health Study.J Pediatr. 2006 Feb;148(2):183-7.

11. Brown RJ, de Banate MA, Rother KI. Artificial sweeteners: a systematic review of metabolic effects in youth. Int J Pediatr Obes. 2010 Aug;5(4):305-12

12. Nettleton JA, Lutsey PL, Wang Y, Lima JA, Michos ED, Jacobs DR Jr. Diet soda intake and risk of incident metabolic syndrome and type 2 diabetes in the Multi-Ethnic Study of Atherosclerosis (MESA). Diabetes Care. 2009 Apr;32(4):688-94.

13. Cohen L, Curhan G, Forman J. Association of sweetened beverage intake with incident hypertension. J Gen Intern Med. 2012 Sep;27(9):1127-34.

14. Gardener H, Rundek T, Markert M, Wright CB, Elkind MS, Sacco RL. Diet soft drink consumption is associated with an increased risk of vascular events in the Northern Manhattan Study. J Gen Intern Med. 2012 Sep;27(9):1120-6.

15. Dhingra R, Sullivan L, Jacques PF, Wang TJ, Fox CS, Meigs JB, D’Agostino RB, Gaziano JM, Vasan RS.Soft drink consumption and risk of developing cardiometabolic risk factors and the metabolic syndrome in middle-aged adults in the community. Circulation. 2007 Jul 31;116(5):480-8.

16. Lutsey PL, Steffen LM, Stevens J. Dietary intake and the development of the metabolic syndrome: the Atherosclerosis Risk in Communities study. Circulation. 2008 Feb 12;117(6):754-61

17. Fagherazzi G, Vilier A, Saes Sartorelli D, Lajous M, Balkau B, Clavel-Chapelon F.
Consumption of artificially and sugar-sweetened beverages and incident type 2 diabetes in the Etude Epidemiologique aupres des femmes de la Mutuelle Generale de l’Education Nationale-European Prospective Investigation into Cancer and Nutrition cohort. Am J Clin Nutr. 2013 Mar;97(3):517-23

18. Greenwood DC, Threapleton DE, Evans CE, Cleghorn CL, Nykjaer C, Woodhead C, Burley VJ. Association between sugar-sweetened and artificially sweetened soft drinks and type 2 diabetes: systematic review and dose-response meta-analysis of prospective studies. Br J Nutr. 2014 Sep 14;112(5):725-34.

19. Abegaz EG, Bursey RG. Formaldehyde, aspartame, migraines: a possible connection. Dermatitis. 2009 May-Jun;20(3):176-7; author reply 177-9

20. Bigal ME, Krymchantowski AV. Migraine triggered by sucralose–a case report. Headache. 2006 Mar;46(3):515-7

21. Jacob SE, Stechschulte S. Formaldehyde, aspartame, and migraines: a possible connection. Dermatitis. 2008 May-Jun;19(3):E10-1.

22. Lipton RB, Newman LC, Cohen JS, Solomon S. Aspartame as a dietary trigger of headache. Headache. 1989 Feb;29(2):90-2

23. Newman LC, Lipton RB. Migraine MLT-down: an unusual presentation of migraine in patients with aspartame-triggered headaches. Headache. 2001 Oct;41(9):899-901.
Araújo JR, Martel F, Keating E. Exposure to non-nutritive sweeteners during pregnancy and lactation: Impact in programming of metabolic diseases in the progeny later in life. Reprod Toxicol. 2014 Sep 28;49C:196-201.

24. Maslova E, Strøm M, Olsen SF, Halldorsson TI. Consumption of artificially-sweetened soft drinks in pregnancy and risk of child asthma and allergic rhinitis.PLoS One. 2013;8(2):e57261.

25. Halldorsson TI, Strøm M, Petersen SB, Olsen SF. Intake of artificially sweetened soft drinks and risk of preterm delivery: a prospective cohort study in 59,334 Danish pregnant women. Am J Clin Nutr. 2010 Sep;92(3):626-33.

26. Englund-Ögge L1, Brantsæter AL, Haugen M, Sengpiel V, Khatibi A, Myhre R, Myking S, Meltzer HM, Kacerovsky M, Nilsen RM, Jacobsson B. Association between intake of artificially sweetened and sugar-sweetened beverages and preterm delivery: a large prospective cohort study. Am J Clin Nutr. 2012 Sep;96(3):552-9.

27. Bandyopadhyay A, Ghoshal S, Mukherjee A. Genotoxicity testing of low-calorie sweeteners: aspartame, acesulfame-K, and saccharin. Drug Chem Toxicol. 2008;31(4):447-57

28. Belpoggi F, Soffritti M, Padovani M, Degli Esposti D, Lauriola M, Minardi F. Results of long-term carcinogenicity bioassay on Sprague-Dawley rats exposed to aspartame administered in feed. Ann N Y Acad Sci. 2006 Sep;1076:559-77.

29. Soffritti M, Belpoggi F, Tibaldi E, Esposti DD, Lauriola M. Life-span exposure to low doses of aspartame beginning during prenatal life increases cancer effects in rats. Environ Health Perspect. 2007 Sep;115(9):1293-7

30. Ferreira AV1, Generoso SV, Teixeira AL. Do low-calorie drinks ‘cheat’ the enteral-brain axis? Curr Opin Clin Nutr Metab Care. 2014 Sep;17(5):465-70.

31. Swithers SE, Martin AA, Davidson TL. High-intensity sweeteners and energy balance. Physiol Behav. 2010 Apr 26;100(1):55-62

32. Yang Q. Gain weight by “going diet?” Artificial sweeteners and the neurobiology of sugar cravings: Neuroscience 2010. Yale J Biol Med. 2010 Jun;83(2):101-8.

33. Swithers SE. Artificial sweeteners produce the counterintuitive effect of inducing metabolic derangements. Trends Endocrinol Metab. 2013 Sep;24(9):431-41.

34. Swithers SE, Davidson TL. A role for sweet taste: calorie predictive relations in energy regulation by rats. Behav Neurosci. 2008 Feb;122(1):161-73.

35. Swithers SE, Baker CR, Davidson TL. General and persistent effects of high-intensity sweeteners on body weight gain and caloric compensation in rats. Behav Neurosci. 2009 Aug;123(4):772-80

36. Swithers SE, Martin AA, Clark KM, Laboy AF, Davidson TL. Body weight gain in rats consuming sweetened liquids. Effects of caffeine and diet composition. Appetite. 2010 Dec;55(3):528-33

37. Feijó Fde M1, Ballard CR, Foletto KC, Batista BA, Neves AM, Ribeiro MF, Bertoluci MC. Saccharin and aspartame, compared with sucrose, induce greater weight gain in adult Wistar rats, at similar total caloric intake levels. Appetite. 2013 Jan;60(1):203-7.

38. Swithers SE, Sample CH, Davidson TL. Adverse effects of high-intensity sweeteners on energy intake and weight control in male and obesity-prone female rats. Behav Neurosci. 2013 Apr;127(2):262-74.

39. Pierce WD, Heth CD, Owczarczyk JC, Russell JC, Proctor SD. Overeating by young obesity-prone and lean rats caused by tastes associated with low energy foods. Obesity (Silver Spring). 2007 Aug;15(8):1969-79.

40. von Poser Toigo E, Huffell AP, Mota CS, Bertolini D, Pettenuzzo LF, Dalmaz C.
Metabolic and feeding behavior alterations provoked by prenatal exposure to aspartame. Appetite. 2014 Dec 24. pii: S0195-6663(14)00774-0.

41. Polyák E, Gombos K, Hajnal B, Bonyár-Müller K, Szabó S, Gubicskó-Kisbenedek A, Marton K, Ember I. Effects of artificial sweeteners on body weight, food and drink intake. Acta Physiol Hung. 2010 Dec;97(4):401-7

42. Malaisse WJ, Vanonderbergen A, Louchami K, Jijakli H, Malaisse-Lagae F. Effects of artificial sweeteners on insulin release and cationic fluxes in rat pancreatic islets. Cell Signal. 1998 Nov;10(10):727-33

43. Swithers SE, Laboy AF, Clark K, Cooper S, Davidson TL. Experience with the high-intensity sweetener saccharin impairs glucose homeostasis and GLP-1 release in rats. Behav Brain Res. 2012 Jul 15;233(1):1-14

44. Berkey CS, Rockett HR, Field AE, Gillman MW, Colditz GA. Sugar-added beverages and adolescent weight change. Obes Res. 2004 May;12(5):778-88.

45. Schiffman SS. Rationale for further medical and health research on high-potency sweeteners. Chem Senses. 2012 Oct;37(8):671-9.

Predicting Childhood Cognitive Performance

How important are socioeconomic factors when it comes to your child’s future academic success? According to a recent report by Child Care Aware America, annual preschool education costs range from $4,500-$12,000 in the US, depending on the state.1 Although President Obama to improve quality and expand access to preschool for lower- and moderate-income families, Parents assume 60% of these costs.2

While preschool education may set the stage for future academic success, are there far less expensive and more effective measures? According to new research published by William Lassek, M.D. and Steven Gaulin, M.D., diet better predicts infants’ future cognitive performance than economics. Specifically, the omega-3 and omega-6 levels of their mothers’ breast milk.3So, where does prenatal and neonatal nutrition come into play?

By comparing the fatty acid profiles of breast milk from women from 28 countries with math, science, and reading ability test results from the Programme for International Student Assessment (PISA), Lassek and Gaulin determined that increased omega-3 docosahexaenoic acid (DHA) and decreased omega-6 linoleic acid levels most strongly predict higher test scores, with no improvements in predictive power when socioeconomic variables were considered. The Paleo Diet is low in omega-6 while featuring the richest dietary sources of DHA—cold-water, fatty fish, particularly salmon, sardines, mackerel, herring, and tuna.

Mothers who consume these fish while pregnant and breastfeeding have higher amounts of DHA in their milk. This was demonstrated in a previous study published by the same authors, among others, comparing the DHA breast milk levels of Tsimane women from Amazonian Bolivia with those of women from Cincinnati. The Tsimane women eat traditional diets consisting primarily of locally grown crops, wild game, and freshwater fish. The Cincinnati women, on the other hand, had typical US diets, including high amounts of trans fats and omega-6 fatty acids (abundant in industrial seed oils, including corn oil and soybean oil).

The Tsimane women’s milk was 400% higher in DHA, 260% lower in trans fats, and 84% lower in omega-6 linoleic acid.4 Lead author Melanie Martin said, “Despite living in economically impoverished conditions, Tsimane mothers produce breast milk that has more balanced and potentially beneficial composition as compared to milk from U.S. mothers.”5 High levels of omega-6 are just as disconcerting as low levels of omega-3 because increased omega-6 consistently predicts lower test scores, according to the Lassek and Gaulin study.

This is not surprising, considering that omega-3 and omega-6 fatty acids both compete for the same rate-limiting enzymes. In other words, the ratio of dietary omega-6 to omega-3 is vitally important. Eating fatty fish several times per week is ideal, but if you’re not concurrently limiting your omega-6 consumption, especially by eliminating seed oils from your diet, you won’t be absorbing enough of that omega-3 from the fish. From an evolutionary perspective, the omega-6 to omega-3 ratio should be roughly 1:1.6 Modern Western diets, however, typically yield ratios ranging from 10:1 to 30:1.7

According to the latest PISA results, US students lag behind students from 29 other nations in math and 22 in science, respectively.8 Is this the result of consuming too little DHA and far too much omega-6? Of the 300-million-plus acres planted with food in the US, half are devoted to soy and corn. Another 50 million go to wheat, with only 14 million acres reserved for fruits and vegetables.9 While these numbers are sobering and perhaps disempowering, change starts with the individual.

So if motherhood is on the horizon, now is the time to start eating a healthy Paleo Diet. Of particular importance to your child’s future cognitive performance is the elimination of all industrial seed oils from your diet, particularly corn, soybean, canola, sunflower, safflower, and grapeseed oils. At the same time, be sure to consume DHA-rich fish from the cleanest sources possible several times per week. Education is important, but clearly so are prenatal and neonatal nutrition.

Christopher James Clark, B.B.A.


Christopher James Clark | The Paleo Diet TeamChristopher James Clark, B.B.A. is an award-winning writer, consultant, and chef with specialized knowledge in nutritional science and healing cuisine. He has a Business Administration degree from the University of Michigan and formerly worked as a revenue management analyst for a Fortune 100 company. For the past decade-plus, he has been designing menus, recipes, and food concepts for restaurants and spas, coaching private clients, teaching cooking workshops worldwide, and managing the kitchen for a renowned Greek yoga resort. Clark is the author of the critically acclaimed, award-winning book, .

references

1. Childcare Aware of America (March 2014). Child Care in America: 2014 State Fact Sheets. Retrieved September 28, 2014 from //usa.childcareaware.org/sites/default/files/19000000_state_fact_sheets_2014_v04.pdf

2. Mitchell, A., Stoney, L., & Dichter, H. (2001). Financing child care in the United States: An expanded catalog of current strategies. Ewing Marion Kauffman Foundation. Retrieved September 28, 2014 from //files.eric.ed.gov/fulltext/ED458932.pdf

3. Lassek, WD., and Gaulin, SJC. (August 2014). Linoleic and docosahexaenoic acids in human milk have opposite relationships with cognitive test performance in a sample of 28 countries. Prostaglandins, Leukotrienes and Essential Fatty Acids. Retrieved September 24, 2014 from //www.plefa.com/article/S0952-3278%2814%2900127-6/abstract

4. Martin, MA., et al., (July 2012). Fatty acid composition in the mature milk of Bolivian forager-horticulturalists: controlled comparisons with a US sample. Maternal & Child Nutrition, 8(3). Retrieved September 24, 2014 from //www.ncbi.nlm.nih.gov/pubmed/22624983

5. University of California at Santa Barbara. (June 9, 2012). Anthropologists finds high levels of omega-3 fatty acids in breast milk of Amerindian women. Press release published by Science Daily. Retrieved September 24, 2014 from //www.sciencedaily.com/releases/2012/06/120609152436.htm

6. Simopoulos, AP. (October 2002). The importance of the ratio of omega-6/omega-3 essential fatty acids. Biomedicine & Pharmacotherapy, 56(8). Retrieved September 24, 2014 from //www.ncbi.nlm.nih.gov/pubmed/12442909

7. Ibid, Simopoulos.

8. Layton, L. (December 3, 2013). U.S. students lag around average on international science, math and reading test. The Washington Post. Retrieved September 24, 2014 from //www.washingtonpost.com/local/education/us-students-lag-around-average-on-international-science-math-and-reading-test/2013/12/02/2e510f26-5b92-11e3-a49b-90a0e156254b_story.html

9. Haspel, T. (February 18, 2014). Farm bill: Why don’t taxpayers subsidize the foods that are better for us? The Washington Post. Retrieved September 24, 2014 from //www.washingtonpost.com/lifestyle/food/farm-bill-why-dont-taxpayers-subsidize-the-foods-that-are-better-for-us/2014/02/14/d7642a3c-9434-11e3-84e1-27626c5ef5fb_story.html

Vegetarian Diet | The Paleo Diet

Did you miss Vegetarian and Vegan Diets: Nutritional Disasters Part 1? Read it HERE

Vegetarian Diets and Homocysteine

Vitamin B12 deficiencies caused by vegetarian or vegan diets are just as devastating to adults as they are to infants and pregnant women. Vitamins technically are defined as “organic catalysts” – meaning that without their presence in our diets, our metabolic machinery slows, or is sufficiently damaged to eventually cause illness and disease. One of the most destructive changes in our bodies caused by vitamin B12 deficiency is the appearance of a toxic substance in our bloodstream known as homocysteine. Without sufficient dietary sources of vitamin B12, a chemical reaction within our bodies is impaired and causes blood concentrations of homocysteine to rise. Homocysteine is a toxin for almost every cell in our bodies, and increases the risk for birth defects, infertility, dementia, psychological illness, stroke, heart attacks, blood vessel disease, blood clots, osteoporosis and overall death rates. Worldwide studies of vegetarians and vegans show that the less animal food they eat, the higher are their blood concentrations of homocysteine.9, 21, 38, 60, 67, 70, 94, 101 Let’s take a look at how vegetarian diets raise blood concentrations of homocysteine and increase the risk for numerous diseases.

Homocysteine and Cardiovascular Disease

It is widely assumed that vegetarian diets reduce the risk for cardiovascular disease and heart attacks because they lower total and saturated fats in our diets. Unfortunately, this simplistic explanation is only part of the story. Total fat and saturated fat have been shown in large meta analyses to have negligible effect upon the atherosclerotic process that clogs the arteries and causes heart and blood vessel disease.143-146 In contrast, meta analyses published in the past 15 years have confirmed that homocysteine is an independent risk factor for cardiovascular disease and heart attacks.61, 130 The higher your blood levels of homocysteine, the greater will be your risk of having a stroke or heart attack. As I mentioned earlier, homocysteine is toxic to almost all cells in our bodies. It is particularly dangerous when high concentrations build up in our bloodstreams because it damages the cells lining blood vessels. This initial injury to the blood vessels represents one of the first steps in the artery clogging process. If blood concentrations of homocysteine remain high and the blood vessel damage goes on unabated for decades, it may result in fatal strokes and heart attacks. A recent (2008) meta analysis by Dr. Humphrey and colleagues indicated that for each (5 micromol/L) increase in blood homocysteine levels, the risk for cardiovascular disease events increased by approximately 20%.61

Because vegetarian diets cause vitamin B12 levels in the bloodstream to plummet, which in turn causes homocysteine levels to dangerously rise, you might expect to find high rates of cardiovascular disease in strict lifelong vegetarians. One of the problems in examining cardiovascular disease in vegetarians from the U.S. and Europe is that many of them aren’t strict vegetarians, and typically haven’t consumed vegetarian diets for their entire lives. All of these variables tend to confound the results of epidemiological studies. Given this scenario, what better place to examine vegetarian diets and than in India? With a population of 1.17 billion people, 31 % (362,700,000) of whom are vegetarians,42 India represents a country which can give us insight into study cardiovascular disease and plant based diets. As opposed to vegetarians in the U.S. and Europe, many Indian vegetarians are committed to lifelong vegetarian diets due to their religious convictions and family conventions.

If vegetarian diets provide protection from cardiovascular disease as the ADA suggests, then you might expect to find a low prevalence of heart disease and stroke in India because almost one third of its population are vegetarians. Unfortunately, this is not the case.137 In reality, the incidence of cardiovascular disease is much higher in India than in most other places in the world. Moreover, Indians develop cardiovascular disease at a much earlier age than people from other countries. In the largest study ever of 368 lifelong Indian vegetarians with cardiovascular disease, Dr. Kumar and co-workers showed that heart disease was higher in vegetarians and that they had lower blood levels of vitamin B12.79 I quote Dr. Kumar, “We believe that the beneficial effect of a vegetarian diet in this population is circumvented by deficiency of vitamin B12.

Homocysteine and Neurological Diseases

Not only is homocysteine toxic to our blood vessels, but numerous studies also have found that it adversely affects brain function, behavior and mood.23, 129 People with higher blood concentrations of homocysteine have a greater risk for Alzheimer’s disease, dementia, depression, Parkinson’s disease and stroke. In a comprehensive 2010 review of 1,627 articles on high blood levels of homocysteine and vitamin B12 Dr. Werder133 concluded that: “Hyperhomocysteinemia (high blood levels of homocysteine) with or without hypovitaminosis B12 (low blood levels of vitamin B12) is a risk factor for dementia.” In addition to vitamin B12 deficiencies another B vitamin, folate, can cause blood concentrations of homocysteine to rise. However in a study involving 2,403 older people, Dr. Clarke and colleagues24 found that, “the relative importance of vitamin B12 deficiency as a determinant of homocysteine concentrations and cognitive impairment is probably greater than that of folate deficiency in older adults.” Additionally, a recent study by Dr. Selhub’s research group showed that high dietary intakes of folate seems to make B12 deficiencies worse by further increasing blood concentrations of homocysteine.114 This is precisely the dietary pattern found in the blood of most vegetarians – low B12 and adequate or elevated folate. Is it any wonder why so many vegetarians and vegans have dangerously high blood levels of homocysteine?

Homocysteine and Bone Disease

The list of chronic diseases associated with high blood concentrations of homocysteine seems almost endless and has recently been extended to bone disease. By raising blood homocysteine levels, vegetarian diets may not only increase your risk for neurological disorders and cardiovascular disease, but they also increase bone fracture risk. The notion that vegetarians have weaker bones than their meat eating counterparts was verified in the largest study ever undertaken in a vegetarian population (9,420 vegetarians and 1,126 vegans). The authors of the EPIC-Oxford study concluded that, “The higher fracture risk in the vegans appeared to be a consequence of their considerably lower mean calcium intake.2 Low calcium and vitamin D intakes are well known risk factors for bone fractures and osteoporosis, and these nutritional deficiencies are common in vegan and vegetarian populations. But to add insult to injury, you can now add another strike against vegan and vegetarian diets in promoting bone disease. Since 2003, numerous studies have identified low B12, low folate or high homocysteine blood levels as risk factors for poor bone density, increased fractures, or osteoporosis.2, 4, 17, 34, 51, 53, 54, 58, 78, 82, 112, 125

Although we don’t completely understand how high blood levels of homocysteine adversely affect bone, tissue studies have identified a number of mechanisms. First homocysteine seems to impair the normal bone mineralization process.17 It also causes an accelerated breakdown of bone and inhibits the formation of new bone cells.51 Some of the best evidence implicating homocysteine in bone disease comes from human dietary interventions. In a two year study of 559 elderly women in Japan, Dr. Sato and fellow researchers showed that supplementation of vitamin B12 and folate reduced blood concentrations of homocysteine by 38%.112 But more importantly women in the vitamin supplemented group suffered 33 fewer hip fractures than women in the un-supplemented control group.

One of the best ways you can prevent hip fractures is to follow The Paleo Diet. Because you will be eating meat and fish at virtually every meal, you won’t have to worry about vitamin B12 deficiencies, as these two foods are our best sources of this essential vitamin. The other mainstay of The Paleo Diet is fresh fruit and veggies which are rich sources of the B vitamin, folate. The combination of lots of meat and fish along with plenty of fruits and vegetables at every meal will ensure that you do not develop vitamin B12 or folate deficiencies and that your blood homocysteine levels will remain low throughout your life – just as nature intended.

Homocysteine and Infertility

Before I leave homocysteine, I’ve got to cover one more topic that for some of you may be the most important revelation of all about this noxious molecule. By now, you know that elevated blood concentrations of homocysteine result primarily from too little vitamin B12 and folate in our diets. When adequate stores of these two B vitamins are present from nutritious foods in our diet (e.g. meats, fresh fruits and veggies), then our cells can defuse the poisonous effects of homocysteine and convert it into less toxic compounds. However, when B12 is lacking or deficient, as it almost always is in vegetarian and vegan diets, then homocysteine builds up in our bloodstream and literally infiltrates nearly every cell in our bodies.

Healthy egg cells in women and healthy sperm cells in men are absolutely essential requirements for getting pregnant, staying pregnant and producing normal embryos, vigorous infants and healthy children. I’ve previously outlined how vitamin B12 deficiencies can elevate blood levels of homocysteine and cause numerous adverse health problems in pregnant women, their unborn fetuses and nursing infants. In addition to these unfavorable effects, a diet deficient or marginal in vitamins B12 and folate can severely reduce your chances for successful fertilization and conception. Infertility is a huge problem in both the U.S. and elsewhere11, 122 and affects at least 6 million people in the U.S. or more importantly about 7.4% of the reproductive age population.119 Many environmental and genetic factors may be involved. However, one thing is certain, as a couple, if you or your partner’s blood levels of vitamin B12 and/or folate are low and your homocysteine is elevated, your chances for a normal conception and pregnancy will be significantly reduced.8, 12-14, 30, 36, 93, 98, 116, 128

The injurious effects of homocysteine in our bones and in our cardiovascular and nervous systems have been much better studied than in our reproductive systems. Nevertheless, it is becoming increasingly evident that the low vitamin B12 and folate status responsible for elevated homocysteine is toxic to both sperm and egg cells and may represent a major, previously unrecognized risk factor for infertility. More than 30 years ago, at least one group of researchers pointed out that Indian vegetarian men maintained lower vitamin B12 concentrations in their sperm than non-vegetarians and attributed these values to their vegetarian diet.65 Additionally, a number of these earlier studies hinted that vitamin B12 supplementation could improve sperm function and vigor and even boost male fertility.57, 65

If we fast forward to the 21st century, in the past five to ten years similar nutritional patterns have been discovered in western populations. In a recent (2009) study of 172 men and 223 women who were unable to conceive, 36% of men and 23% of women had vitamin B12 deficiencies. Almost 40% of the infertile men had abnormal semen that was directly related to their vitamin B12 deficiencies. Other recent studies in men show that low dietary folate and vitamin B12 are associated with high blood concentrations of homocysteine that likely underlie abnormal sperm function. On the flip side of the equation, women with compromised dietary B12 and folate intakes frequently have elevated blood levels of homocysteine68 which prevent them from becoming pregnant. We are not completely sure how these blood chemistry changes impede successful pregnancies in women, but tissue studies suggest that egg cells infiltrated by homocysteine and deficient in vitamin B12 and folate make them fragile and unable to continue with a normal pregnancy once fertilized.13, 126

Vegetarian Diets: Additional Fertility Problems

Menstrual Problems caused by Vegetarian Diets

In addition to B vitamin deficiencies and elevated blood concentrations of homocysteine, vegetarian diets are frequently associated with menstrual problems known to affect fertility. A total of five studies have compared the incidence of menstrual irregularities between vegetarians and meat eaters. Four out of these five studies demonstrated significantly higher rates of menstrual complications in vegetarians. Not all types of scientific experiments have equal clout in establishing cause and effect. Of the five studies, four were epidemiological (population) studies and one was an actual experimental intervention. Because dietary interventions represent the most powerful experimental procedure for determining if dietary changes improve health or cause illness, they carry more weight than epidemiological studies. Let’s take a look at the only dietary intervention investigating vegetarian diets on menstrual health.

Dr. Pirke and researchers at the University of Trier in Germany randomly divided 18 young women with normal menstrual periods into either vegetarian or non-vegetarian diet groups. After six weeks, 7 of the 9 women assigned to the vegetarian diet stopped ovulating, whereas only a single woman in the meat eating group experienced this problem.147 The results of this experiment are shocking. Within only six weeks of consuming a vegetarian diet, 78% of healthy, normally cycling women ceased ovulating. The takeaway: if you are trying to get pregnant, one of your best strategies is to avoid vegetarian diets. While you’re at it, make sure your husband or partner does the same.

Zinc Deficiencies Impair Sperm Function

One of the most frequent nutritional shortcomings of vegetarian and vegan diets is that they fall short of recommended intakes for zinc. In the largest epidemiological study ever of vegetarians (The EPIC-Oxford Study) Dr. Davey and colleagues noted that vegans had “…the lowest intakes of retinol [vitamin A], vitamin B12, vitamin D, calcium and zinc” when compared to meat and fish eaters.31 More importantly, with zinc it’s not just how much is present in your food, but how much is actually absorbed in your body. Although dietary zinc intakes in vegetarian diets sometimes appear to be adequate on paper – in the body they actually result in deficiencies32, 44, 45, 62 because most of plant based zinc is bound to phytate and, therefore, unavailable for absorption. Phytate is an antinutrient found in whole grains, beans, soy and other legumes that prevents normal assimilation of many minerals. Laboratory experiments show that vegetarians only absorb about half as much zinc as meat eaters because zinc from animal food is much better assimilated than from plant foods.

Based upon this information, you might expect blood concentrations of zinc to be lower in vegetarians than meat eaters. Sometimes scientists have found this to be the case, but not always. The problem here has to do with where zinc ends up in our bodies after we ingest it. Most zinc finds its way into the interior of cells and does not accumulate in the liquid portion (plasma) of blood. Consequently, unless scientists examine zinc concentrations within cells, readings obtained in blood plasma frequently do not accurately reflect body stores of this essential mineral. In virtually every study of vegetarians which measured zinc levels inside various cells (red blood cells, hair cells and skin cells in saliva), plant based diets caused zinc deficiencies. In one study, 12 meat eating women were put on a lacto-ovo vegetarian diet, and after only 22 days Dr. Freeland-Graves and co-workers reported that zinc concentrations in the women’s salivary cells plunged by 27%.44 Similar results were described by Dr. Srikumar and colleagues from a longer term experiment in which 20 meat eating men and women adopted a lactovegetarian diet for an entire year.117 In this study, both hair cells and blood levels of zinc sharply declined and remained low throughout the 12 month experiment.

So, I’ve set the stage for zinc deficiencies and infertility problems. Because of their low zinc content and bioavailability, long term vegetarian diets almost always cause zinc deficiencies.20, 32, 44, 45, 62 Numerous studies have shown that infertile/subfertile men had poor seminal quality that was associated with vegetarian diets6, 65 or reduced zinc levels in their semen. Virtually every well controlled experimental study ever conducted shows that men put on zinc deficient diets ended up with reduced sperm counts, impaired sperm health and often depressed blood testosterone levels. The good news is that these deleterious changes in male reproductive function can be reversed if zinc rich diets (e.g. The Paleo Diet) are consumed, or if zinc pills are supplemented.136 Dr. Steegers-Theunissen’s research group in the Netherlands showed dramatic improvements in the reproductive health of 103 sub-fertile men when zinc and folic acid were supplemented.37 Following the six month supplementation program, sperm counts increased significantly in the sub-fertile men while sperm abnormalities declined by 4%. A similar study of 14 infertile men from India also indicated that zinc supplementation increased sperm health, sperm counts and shortly thereafter resulted in three successful conceptions by these men’s wives.123

Whether you are a man or woman, if you want to sidestep infertility problems, the best advice I can give you is to abandon vegetarian diets and adopt the nutritional patterns that have sustained our hunter gatherer ancestors for the past 2.6 million years. There are no known risks to adopting The Paleo Diet, and in fact, regular consumption of meat, seafood and fresh fruit and vegetables at the expense of cereals, dairy and processed foods will prevent vitamin B12 and folate deficiencies. In turn these essential vitamins will ensure that your blood levels of homocysteine will return to normal – effectively reducing your risk for cardiovascular, neurological, bone and reproductive diseases.

In Vegetarian and Vegan Diets: Nutritional Disasters Part 3 we’ll discuss the additional copious shortcomings of vegetarian and vegan diets and why The Paleo Diet is optimal for health and wellbeing.

Cordially,

Loren Cordain, Ph.D., Professor Emeritus

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Infertility | The Paleo Diet

One of the numerous benefits from eating “Paleo” or switching to a contemporary Paleo Diet if you eat in the standard American way is that you and your spouse/partner/ will greatly improve your chances for successful conception, pregnancy and a healthy baby. Here’s the information you may want to become acquainted with, particularly if you have avoided meats and fish and have previously focused upon whole grain cereals, legumes and processed foods in your diet.

If you fail to regularly eat animal foods (eggs, meat, fish and seafood) you will become deficient in vitamin B12 because plant food sources contain no B12. Further plant foods do not contain the specific types of vitamin B6 which are readily absorbable in the human gut. Accordingly, diets devoid of or lacking in animal proteins, will invariably be deficient in vitamin B12 and vitamin B6. Deficiencies or insufficiencies in these vitamins ultimately increase the level of homocysteine in our blood.

Elevated blood concentrations of homocysteine result primarily from too little vitamin B12. B6 and folate in our diets. When adequate stores of these B vitamins are present from nutritious foods in our diet (e.g. meats, fresh fruits and veggies), then our cells can defuse the poisonous effects of homocysteine and convert it into less toxic compounds. However, when B12 is lacking or deficient, as it almost always is in vegetarian and vegan diets, then homocysteine builds up in our bloodstream and literally infiltrates nearly every cell in our bodies.

Healthy egg cells in women and healthy sperm cells in men are absolutely essential requirements for getting pregnant, staying pregnant and producing normal embryos, vigorous infants and healthy children. Vitamin B12 deficiencies can elevate blood levels of homocysteine and cause numerous adverse health problems in pregnant women, their unborn fetuses and nursing infants. In addition to these unfavorable effects, a diet deficient or marginal in vitamins B12, B6 and folate can severely reduce your chances for successful fertilization and conception.

Infertility is a huge problem in both the U.S. and Europe and affects at least 6 million people in the U.S. or more importantly about 7.4 % of the reproductive age population. Many environmental and genetic factors may be involved. However, one thing is certain, as a couple, if you or your partner’s blood levels of vitamin B12, B6 and/or folate are low and your homocysteine is elevated, your chances for normal conception will be significantly reduced.

It is becoming increasingly evident that the low vitamin B12, B6 and folate status responsible for elevated homocysteine is toxic to both sperm and egg cells and may represent a major, previously un-recognized risk factor for infertility. More than 30 years ago, at least one group of researchers pointed out that Indian vegetarian men maintained lower vitamin B12 concentrations in their sperm than non-vegetarians and attributed these values to their vegetarian diet. Additionally, a number of these earlier studies hinted that vitamin B12 supplementation could improve sperm function and vigor and even boost male fertility.

If we fast forward to the 21st century, in the past five years similar nutritional patterns have been discovered in western populations. In a recent (2009) study of 172 men and 223 women who were unable to conceive, 36 % of men and 23 % of women had vitamin B12 deficiencies. Almost 40 % of the infertile men had abnormal semen that was directly related to their vitamin B12 deficiencies. Other recent studies in men show that low dietary folate and vitamin B12 are associated with high blood concentrations of homocysteine that likely underlie abnormal sperm function. On the flip side of the equation, women with compromised dietary B12 and folate intakes frequently have elevated blood levels of homocysteine which prevent them from becoming pregnant. We are not completely sure how these blood chemistry changes impede successful pregnancies in women, but tissue studies suggest that egg cells infiltrated by homocysteine and deficient in vitamin B12 and folate make them fragile and unable to continue with a normal pregnancy once fertilized.

Menstrual Problems caused by Vegetarian and Low Meat Diets

In addition to B vitamin deficiencies and elevated blood concentrations of homocysteine, vegetarian/low meat diets are frequently associated with menstrual problems known to affect fertility. A total of five studies have compared the incidence of menstrual irregularities between vegetarians and meat eaters. Four out of these five studies demonstrated significantly higher rates of menstrual complications in vegetarians. Let’s take a look at the only randomized controlled trial investigating vegetarian diets on menstrual health.

Dr. Pirke and researchers at the University of Trier in Germany randomly divided 18 young women with normal menstrual periods into either vegetarian or non-vegetarian diet groups. After six weeks, 7 of the 9 women assigned to the vegetarian diet stopped ovulating, whereas only a single woman in the meat eating group experienced this problem. The results of this experiment are shocking – within only six weeks of consuming a vegetarian diet, 78% of healthy, normally cycling women ceased ovulating. The take home message is this: if you are trying to get pregnant, one of your best strategies is to avoid vegetarian diets. While you’re at it, make sure your husband or partner does the same.

Zinc Deficiencies Impair Sperm Function

One of the most frequent nutritional shortcomings of vegetarian and vegan diets is that they fall short of recommended intakes for zinc. In the largest epidemiological study ever of vegetarians (The EPIC-Oxford Study) Dr. Davey and colleagues noted that vegans had “. . . the lowest intakes of retinol [vitamin A], vitamin B12, vitamin D, calcium and zinc. . .” when compared to meat and fish eaters. More importantly, with zinc it’s not just how much is present in your food, but how much is actually absorbed in your body. Although dietary zinc intakes in vegetarian diets sometimes appear to be adequate on paper – in the body they actually result in deficiencies because most of plant based zinc is bound to phytate and therefore unavailable for absorption. Phytate is an antinutrient found in whole grains, beans, soy and other legumes that prevents normal assimilation of many minerals. Laboratory experiments show that vegetarians only absorb about half as much zinc as meat eaters because zinc from animal food is much better assimilated than from plant foods.

Based upon this information, you might expect blood concentrations of zinc to be lower in vegetarians than meat eaters. Sometimes scientists have found this to be the case, but not always. The problem here has to do with where zinc ends up in our bodies after we ingest it. Most zinc finds its way into the interior of cells and does not accumulate in the liquid portion (plasma) of blood. Consequently, unless scientists examine zinc concentrations within cells, readings obtained in blood plasma frequently do not accurately reflect body stores of this essential mineral. In virtually every study of vegetarians which measured zinc levels inside various cells (red blood cells, hair cells and skin cells in saliva), plant based diets caused zinc deficiencies. In one study, 12 meat eating women were put on a lacto-ovo vegetarian diet, and after only 22 days Dr. Freeland-Graves and co-workers reported that zinc concentrations in the women’s salivary cells plunged by 27%. Similar results were described by Dr. Srikumar and colleagues from a longer term experiment in which 20 meat eating men and women adopted a lactovegetarian diet for an entire year. In this study, both hair cells and blood levels of zinc sharply declined and remained low throughout the 12 month experiment.

So, I’ve set the stage for zinc deficiencies and infertility problems. Because of their low zinc content and bioavailability, long term vegetarian diets almost always cause zinc deficiencies. Numerous epidemiological studies have shown that infertile men had poor sperm counts that were associated with reduced zinc levels in their semen. Virtually every well controlled experimental study ever conducted shows that men put on zinc deficient diets ended up with reduced sperm counts, impaired sperm health and often depressed blood testosterone levels. The good news is that these deleterious changes in male reproductive function can be reversed if zinc rich diets (e.g. The Paleo Diet) are consumed, or if zinc pills are supplemented. Dr. Steegers-Theunissen’s research group in the Netherlands showed dramatic improvements in the reproductive health of 103 sub-fertile men when zinc and folic acid were supplemented. Following the six month supplementation program, sperm counts increased significantly in the sub-fertile men while sperm abnormalities declined by 4 %. A similar study of 14 infertile men from India also indicated that zinc supplementation increased sperm health, sperm counts and shortly thereafter resulted in three successful conceptions by these men’s wives.

Whether you are a man or woman, if you want to sidestep infertility problems, the best advice I can give you is to abandon vegetarian/low meat diets and adopt the nutritional patterns that have sustained our hunter-gatherer ancestors for the past 2.6 million years. There are no known risks to adopting The Paleo Diet, and in fact, regular consumption of meat, seafood and fresh fruit and vegetables at the expense of cereals, dairy and processed foods will prevent vitamin B12 and folate deficiencies. In turn these essential vitamins will ensure that your blood levels of homocysteine will return to normal – effectively reducing your risk for cardiovascular, neurological, bone and reproductive diseases.

Cordially,

Loren Cordain, Ph.D., Professor Emeritus

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Childbearing | The Paleo Diet

Dr. Cordain,

I had a thought that I suspect occurred to you as well. I had a patient who at 42 had a baby at home 8 yrs after her last one and had been on Paleo for 12 months prior and described it as, “… a very different experience, I told my husband about an hour after that baby was born, my gosh honey, I could do that again. Dr. Sebring, it may sound strange but pushing that baby out was almost orgasmic.”

I don’t know about hunter-gatherers but I suspect they do not have the degree of difficulty modern women have delivering babies. Your research has been of magnificent importance to the health of our small town.

Lane Sebring M.D

Fibromyalgia, Pregnancy, Calcium | The Paleo Diet

Hello Dr. Cordain,

I was wondering if you would tell me if I can start The Paleo Diet while pregnant? I’m coming up to 17 weeks and suffer from Fibromyalgia. My doctor recommended this diet regiment. He advised I cut out pulses, which I eat a lot of, and wheat, which I don’t often eat much of, and to cut dairy products. But, I thought calcium intake was very important during pregnancy? I also use soy milk in cereals and the soy shakes. I was told to stop consuming all of these foods for a month or so to see how I feel. My stomach feels less bloated and I feel better, but feel I may need longer than a month on this diet to relieve aches and pains induced by my condition. I know some people suffer terribly from Fibromyalgia everyday, but my symptoms come and go. I look forward to hearing from you.

Marina

Dr. Cordain’s Response:

Marina,

The Paleo Diet excludes all grains, dairy, legumes, soy, sugar, unbalanced oils, and processed foods. The Paleo Diet emphasizes eating nutrient dense anti-inflammatory food that is derived from the earth in an unprocessed state. These foods include sustainably raised meat, fruit, vegetables, seeds, nuts, and healthy oils like coconut and olive.

Fibromyalgia is characterized by chronic and sometimes severe pain throughout the entire human body. Its exact cause has yet to be determined, but many people have had success healing their Fibromyalgia with The Paleo Diet.

I would strongly advise you to cut out wheat, dairy, and soy to treat your condition and to reduce overall inflammation in your body. Many people believe that soy milk is a healthy alternative to dairy-based milk for meeting the human calcium requirement. In reality, soy milk has many harmful properties that can actually inhibit absorption of calcium and other vital minerals and nutrients. Increasing you intake of fish is not only a good source of calcium, but it is also very rich in Omega-3 which is essential to development.

Many individuals who adopt The Paleo Diet question whether their calcium intake is sufficient, especially during pregnancy if dairy products are not permitted.

Foods that Naturally Contain High Levels of Calcium and Magnesium

Fish
  • Sardines
  • Salmon
  • Other small fish with soft cooked bones
Leafy Greens
  • Spinach
  • Kale
  • Lettuce chard
  • Arugula
Bone Broth
Dried Fruit
  • Apricots
  • Figs

All of the options above should provide your body with an adequate amount of calcium. It’s also worth mentioning that Vitamin D is an absolutely necessary component for synthesizing calcium and magnesium. Modern society emphasizes a lifestyle that is based on “indoor” activities. You can take all the calcium your heart desires, but if you are deficient in Vitamin D your calcium levels can still remain deficient!

The number one source of Vitamin D is sunlight. Spending only twenty minutes a day in full sunlight can provide your body with the necessary levels of vitamin D required for synthesizing calcium. If you live at a latitude that receives little sunlight, or if you lead a busy lifestyle that prevents you from getting outdoors, than you should take a Vitamin D supplement. A dosage of 2000 IU of Vitamin D per day is adequate for most adults. If you still feel that you are unable to meet your calcium requirements, you may want to consider taking a calcium supplement or drinking pure water that has been fortified with calcium.

Cordially,

Loren Cordain, Ph.D., Professor Emeritus

Folic Acid | The Paleo Diet

Dr. Cordain,

I just heard a study reported on NPR that reported that women who took folic acid supplements during early pregnancy reduced autism in their children. This conflicts directly with the info in your latest book, The Paleo Answer, about recommendations for folic acid supplements. Where do you stand on this? My wife and I are trying to have a baby I am unsure what to do with this new info.

Dr. Cordain’s Response:

I stand by the more comprehensive data (and not a single study reported in NPR) I have compiled in my most recent book, with a myriad of references (check those, and decide for yourself!). 

Folic acid is not necessarily equivalent in vivo to folate as they are two separate compounds. Folic acid from supplements must be converted into folate in the liver. Women need adequate folate stores to prevent neural tube defects (spina bifida in particular). Folate compromised women (which is a common situation among women who consume a typical western diet low in leafy greens, fruits and organ meats) can increase their body concentrations of folate by consuming artificial folic acid found in vitamins or fortified cereals.

Nevertheless, but there are metabolic and physiologic problems associated with folic acid supplementation which I fully describe in The Paleo Answer.  My suggestion to couples contemplating pregnancy and producing healthy children free of neural tube defects would be to reduce or eliminate processed foods which contain little folate and replace them with leafy greens, fruits, organ meats and other naturally occurring foods rich in folate.

Cordially,

Loren Cordain, Ph.D., Professor Emeritus

 
 
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