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Raw Vegan Diets
What We Know
› A raw vegan diet consists of foods that are plant based, contain no animal products, dairy
or eggs, and are not cooked or heated to temperatures of more than about 116–118 degrees
Fahrenheit. The percentage of raw foods consumed in the diet can range from 50–100
percent. Some individuals who are raw vegans may also consume raw meat like carpaccio
or sushi and raw milk products. Raw food diets are not advised for infants and children
because of concerns with inadequate nutrient content. Raw food diets can be traced back
to the Pythagoreans who advocated for this type of diet. At the beginning of the 19th
century German immigrants settling in the Southern California region brought the concept
of the diet to the United States. Then in the 1960s the diet was further popularized by
the Hippocrates Health Institute. While there is limited research on raw vegan diets,
there is a fair amount of research on vegetarian or vegan diets. There are different types
of vegetarian diets that can be described on a continuum ranging from those allowing
the eating limited amounts of meat, poultry, fish, shellfish, eggs, and dairy to those who
consume no animal products. In addition to plant-based foods, a semi-vegetarian eats
meat, poultry, fish, shellfish, eggs, and dairy but consumes limited amounts of red meat
and poultry. Pesco-vegetarians do not eat meat or poultry but do consume fish, shellfish,
eggs, and dairy. Vegetarians do not consume meat, fish, poultry, eggs, and dairy while
vegans do not consume any products that come from animal sources.(4,9,10,11,16)
• Advocates of the raw food diet generally believe that raw food is healthier than cooked
foods and that cooked foods can be toxic or poisonous. There is some evidence that
supports the notion that raw foods can be healthier than cooked foods; however, cooking
can also break down components of food that may interfere with absorption of minerals
and make some nutrients better available for absorption. Some raw food advocates also
believe that eating raw foods will increase lifespan because of the digestive enzymes
in raw foods prevent the body from using its own enzymes. However, stomach acid
destroys most of the enzymes in raw food(9,10,12)
–For example, cooking vegetables, particularly boiling can decrease the amount of
water-soluble vitamins and phytonutrients present. Steaming vegetables, however, is
a better cooking method for preserving nutrient content of vegetables. Cooking some
vegetables, such as those that contain carotenoids, actually increases the bioavailability
Author
Lori Porter, RD, MBA
Cinahl Information Systems, Glendale, CA
Reviewer
Anne Danahy, RDN, MS
Cinahl Information Systems, Glendale, CA
Editor
Sharon Richman, MSPT
Cinahl Information Systems, Glendale, CA
of carotenoids(10,17,18)
–Insoluble fiber in vegetables decreases with cooking making it easier to consume
greater amounts
–In reducing sugars, like glucose and fructose, heat leads to the Maillard reaction
(a chemical reaction between amino acids and reducing sugars that provides the
flavor aspect of browned foods), which compromises amino acids, causing protein to
cross-link with reducing sugars making them more difficult to digest
› While there is limited research on the nutritional adequacy and effects of eating a raw
vegan diet, studies on vegan diets suggest that vegan diets can be nutritionally adequate
with attention to select nutrients and that a vegan diet can be beneficial for health
including weight loss, blood pressure control, ischemic heart disease,the gut microbiota,
and metabolic syndrome(2,3,6,7,13,15,16)
November 18, 2016
Published by Cinahl Information Systems, a division of EBSCO Information Services. Copyright©2016, Cinahl Information Systems. All rights
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or information given herein or errors/omissions in the text. It is merely intended as a general informational overview of the subject for the healthcare
professional. Cinahl Information Systems, 1509 Wilson Terrace, Glendale, CA 91206
• With the exception of vitamin B12 and potentially vitamin D, all nutrients can be obtained by a plant-based diet.
Individuals who consume vegan diets with no sources of animal products are at highest risk for developing a vitamin B12
deficiency. Other nutrients that may be of concern for vegans include calcium, iron, iodine, selenium, and zinc. However,
with proper food selection and consumption these nutrients can be adequate in the vegan diet(5,7,14,15)
• Plant-based diets have been shown to be more effective at reducing weight than diets containing meat(2,16)
• Raw and cooked vegetables have been shown to favorably affect blood pressure control. Using participants from the
International Study of Macro/Micronutrients and Blood Pressure (INTERMAP), dietary recalls, and blood pressure
measurements researchers found a significant inverse relationship between raw and cooked vegetable consumption and
blood pressure. The inverse relationship was stronger for raw vegetables(3)
• The gut microbiota of vegans appears to be different from that of those who consume meat. The vegan gut microbiota
appears to have a reduced number of pathobiots (disease causing pathogens) and a greater amount of protective
pathogens. Vegans also seem to be deficient in the gut microbiota that converts dietary L-carnitine(found in red meat) to
trimethylamine-N-oxide (TMAO). High levels of TMAO have been linked to heart attack and stroke risk(6)
• Vegetarian and vegan diets appear to be effective at lowering the risk of metabolic syndrome related issues such as
impaired glucose metabolism, central obesity, increased blood pressure and dyslipidemia(15)
• Vegan diets do not appear to negatively affect bone mineral density long-term. In a study examining the relationship
between veganism and loss of bone mass in postmenopausal women, researchers found that a vegan diet did not adversely
affect loss of bone mass and rates of fractures. However, the use of corticosteroids and high intakes of animal protein and
lipids correlated with bone mass loss(8). However in another study where researchers examined the effect of a vegan diet
on bone mineral density in parents and children, researchers found that inadequate intakes of calcium and vitamin D could
impair the rate of bone turnover and cause bone mineral density to decrease in vegans. The researchers suggested that bone
mineral density should be monitored in vegans, especially children(1)
What We Can Do
› Learn about raw vegan and vegan diets so you can accurately assess your patient's personal characteristics and health
education needs; share this information with your colleagues
• Advise vegans to ensure adequate intake of vitamin B12 and D. Sources of vitamin B12 for vegans in include fortified
foods such as nutritional yeast, cereals, and plant-based milks and supplementation. Sources of vitamin D for vegans
include fortified plant milks; supplementation may be required if there is deficiency
• Encourage vegans to consume adequate sources of other nutrients that may be of concern in the diet such as calcium iron,
iodine, zinc and selenium
–Calcium sources: leafy greens, tofu containing calcium almonds, almond butter, fortified plan milks, sesame seeds, tahini,
figs, and blackstrap molasses
–Iron sources: legumes, leafy greens, soybeans and soy foods, quinoa, potatoes, dried fruit, dark cholate, tahini, seeds, and
sea vegetables
–Iodine sources: sea vegetables and iodized salt
–Zinc sources: legumes, soy foods, nuts, seeds, oats
–Selenium sources: brazil nuts, whole grains, legumes, vegetables, seeds, and other nuts
Related Resources
› The Vegan Society
› Vegetarian Diet
› Vegetarian Nutrition Dietetic Practice Group
› Physician Committee for Responsible Medicine
› USDA National Agricultural Library – Vegetarian Nutrition
› Davis, B., & Melina, V. (2010). Becoming raw: The essential guide to raw vegan diets. Summertown, TN: Book Publishing
Company
References
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biochemical bone turnover markers. Pediatric Endocrinology, Diabetes and Metabolism, 16(3), 201-204. (R)
2. Barnard, N. D., Levin, S. M., & Yokoyama, Y. (2015). A systematic review and meta-analysis of changes in body weight in clinical trials of vegetarian diets. Journal of the
Academy of Nutrition & Dietetics, 115(6), 954-969. doi:10.1016/j.jand.2014.11.016 (M)
3. Chan, Q., Stamler, J., Brown, I. J., Daviglus, M. L., Van Horn, L., Dyer, A. R., ... Elliott, P. (2014). Relation of raw and cooked vegetable consumption to blood pressure: The
INTERMAP study. Journal of Human Hypertension, 28(6), 353-359. doi:10.1038/jhh.2013.115 (R)
4. Driggers, J. (2013). Vegetarian? Vegan? Raw Diet! What’s the difference? Retrieved October 28, 2016, from http://vegetariannutrition.net/?s=raw+vegan (GI)
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7. Hever, J. (2016). Plant-based diets: A physician’s guide. The Permanente Journal, 20(3), 93-101. doi:10.7812TPP/15-082 (X)
8. Ho-Pham, L. T., Vu, B. Q., Lai, T. Q., Nguyen, N. D., & Nguyen, T. V. (2012). Vegetarianism, bone loss, fracture and vitamin D: A longitudinal study in Asian vegans and
non-vegans. European Journal of Clinical Nutrition, 66(1), 75-82. doi:10.1038/ejcn.2011.131 (R)
9. Jennings, J., & Cheng, M. (2011). Does eating a raw food diet cause spleen qi deficiency? Journal of Chinese Medicine, (97), 50-54. (R)
10. Link, L. B., & Jacobson, J. S. (2008). Factors affecting adherence to a raw vegan diet. Complementary Therapies in Clinical Practice, 14(1), 53-59. doi:10.1019/
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14. Pawlak, R., Lester, S. E., & Babatunde, T. (2014). The prevalence of cobalamin deficiency among vegetarians assessed by serum vitamin B12: A review of the literature.
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