Currently, research exploring plant-based diets in the treatment of autoimmune diseases is lacking. Meanwhile, there is an increasing incidence of autoimmune conditions in the United States (2). Autoimmune diseases are the third most common category of disease in the United States behind cancer and heart disease; they affect approximately 5%–8% of the population or 14-22 million persons (3, 4).
Conventional western medical treatment modalities for autoimmune diseases are predominantly pharmacological and frequently accompanied by harmful side effects, additional expenses, and ineffective outcomes (5). Furthermore, minimal advancements in treatment of autoimmune diseases have been made. For example, only one treatment has been successfully trialed for SLE in the last 50 years, and its success has not yet been seen (6).
For the last 25 years, multiple studies have been published documenting the effectiveness of plant-based diets in RA (7-10). Several medical doctors, with expertise in nutrition, have proposed high nutrient plant-based diets as an effective treatment for autoimmune conditions (11, 12). Therefore, it is appropriate to examine this less traveled, conservative, nutritional approach from which some claim a newly found success in controlling their autoimmune disease (13, 14).
In many cases, a vegetarian diet alone helps substantially (15). Vegetarian diets have been demonstrated to prevent obesity in children and are connected with a lower body mass index in adults (16, 17). It is known that obesity is associated with chronic inflammation. Fat tissue produces a large number of hormones and inflammatory molecules, and obesity-related inflammation is said to be the link between excess body fat and chronic disease (18).
Eating more plant foods and fewer animal products, processed foods, and oils is advisable to avoid pro-inflammatory outcomes. A western diet – defined by high-fat, low-calcium, and vitamin D content – increases susceptibility to inflammation, induces oxidative stress and dysregulates immune response contributing to the development of diseases of affluence such as cancer, diabetes, heart disease and autoimmune illnesses (19, 20). Optimal health depends on the proper balance of fatty acids in the diet. In fact, it has been suggested that human beings evolved on a diet with a ratio of omega-6 to omega-3 fatty acids (FA) of about 1/1; whereas today, Western diets have a ratio of 10/1 to 20-25/1. This indicates that Western diets supply an excessive amount of omega-6 fat, but often too little omega-3 fat (21). A deficiency of omega-3 fats has potentially serious health implications. Also, the consumption of too much omega-6 fat leads to high levels of arachidonic acid (AA). Higher levels of AA can promote inflammation (22). In contrast, omega-3 fatty acids found in some whole foods such as green vegetables, soybeans, walnuts, and flax, chia and hemp seeds are known to have anti-inflammatory effects (23).
Fruits and vegetables have been shown to be protective against chronic disease related to their marked reductions in pro-inflammatory and oxidative stress markers (24-27). This results from their low calorie density and high quantity of micronutrients and antioxidants. In an observational study using a semi-quantitative food frequency questionnaire including 13 fruit and 11 vegetable items, fruits and vegetables (>660 g/d) were associated with reduced circulating inflammatory molecules. This suggests a beneficial effect of high fruit and vegetable consumption on decreasing pro-inflammatory status by affecting gene expression in circulating white blood cells and limiting the production of inflammatory molecules by those cells (28). These findings can be used therapeutically by incorporating generous quantities of fresh produce daily.
Recommendations for increasing intake of fruits and vegetables can be easily met by blending green smoothies, soups, and salads. A blended salad is a mixture of raw, leafy greens and other whole foods blended together to make a smooth, creamy salad with a baby-food-like consistency. Eating a salad prepared in this manner is quick and convenient, while enhancing the release of valuable precursors (29). Fruits, nuts, seeds and/or dates, can be added to provide higher levels of nutrients and a new eating experience.
There is evidence indicating that dietary modulation has the potential to prevent or ameliorate autoimmune illnesses such as SLE (30). In addition to successfully prolonging lifespan for those with an autoimmune disease, it is also important to consider how to enhance one’s quality of life. Cruciferous vegetables contain phytochemicals with unique abilities to modify human hormones, detoxify compounds, and prevent toxic compounds from binding to human DNA, preventing toxins from causing DNA damage that could lead to cancer (29). Also known as the Brassica family, crucifers such as broccoli, Brussels sprouts, cabbage, kale, collards, bok choy, watercress and arugula are rich sources of sulfur-containing compounds called glucosinolates (29). Crucifers contain a variety of glucosinolates, for example, eight glucosinolates have been identified in kale and cabbage and 11 in leaf rape alone (31). Each one forms a unique isothiocyanate (known to provide a “bitter” taste) when split or hydrolyzed (32). When cruciferous vegetables are chewed, chopped or blended the enzyme myrosinase is activated from the cell walls to catalyze the hydrolysis of glucosinolates, releasing isothiocyanates from their precursors (29). Blending enhances the mastication process and it is thorough mastication of raw crucifers that increases glucosinolate contact with plant myrosinase, thereby increasing the amount of isothiocyanates absorbed.
It is important to note, that the absorption and excretion of isothiocyanates is lowered substantially in cooked verses raw cruciferous vegetables (33-35). However, even when plant myrosinase is completely inactivated by heat, the human intestinal bacteria enzyme (myrosinase) activity allows some formation and absorption of isothiocyanates (36). Isothiocyanate metabolites are measurable in the urine and highly correlated with consumption of cruciferous vegetable consumption (37).
Isothiocyanates play key roles in the metabolism and elimination of a variety of chemicals including drugs, toxins, and carcinogens (38). As a result, these good sources of glucosinolates and phenolic antioxidants are some of the healthiest foods on the planet (29)! In fact, scientific research has shown a strong positive association between the consumption of vegetables, including crucifers, and a reduction of all the leading causes of death in humans (39). Therefore, it is imperative to include crucifers; both blended and chewed well, in a therapeutic plant-based diet when treating chronic diseases of all types.
As a vital part of the health care team, registered dietitians have the ability to focus on nutrients that reduce inflammation and eliminate toxins from the body, rather than basing care around pharmacologic strategies with severe repercussions - such as increased malignancy risk with immunosuppressive drug exposure (40,41). By minimizing animal products, processed foods, and omega-6 fatty acids and increasing consumption of high nutrient, plant-based, whole foods and in particular daily inclusion of omega-3 fatty acid food sources, blended soups, salads and smoothies, dark leafy greens and high cruciferous vegetables; the human body is better equipped to face immune, environment, and life stressors.
These guidelines are universal in their application. In an ideal world, such aggressive nutritional parameters would be suggested to everyone, from those suffering with a chronic disease to the athlete in peak physical condition. The bounty of a high nutrient vegetable intake is fruitful, particularly in the treatment of persons with autoimmune diseases, whose bodies are often laden with toxic drugs and inflammation. To be truly well, large quantities of vegetables should be prepared and consumed in a variety of delicious methods to successfully embark on the journey toward optimal health.
This article was written and published by Lis Rodriguez, RDN for The Vegetarian Nutrition Dietetic Practice Group in 2012.
1. Jacobsona DL, Gangea SJ, Roseb NR, Grahama NMH. Epidemiology and Estimated Population Burden of Selected Autoimmune Diseases in the United States. Clinical Immunology and Immunopathology. September 1997;84(3):223.
2. Bach JF. Why is the incidence of autoimmune diseases increasing in the modern world? Endocrine Abstracts. 2008;16:S3.1.
3. National Institutes of Health Autoimmune Disease Coordinating Committee Report. The Institutes. 2002.
4. Fairweather D, Fairweather N, Rose R. Women and Autoimmune Diseases. Emerging Infectious Diseases. 2004;10(11):2005.
5. Schiavo AL, Puca RV, Ruocco V, Ruocco E. Adjuvant drugs in autoimmune bullous diseases, efficacy versus safety: Facts and controversies. Clinical Dermatology. May-June 2010;28(3):337-343.
6. Lupus Foundation of America. 2009: A Year of Many Firsts in Efforts to Overcome Lupus. Lupus Foundation of America, Inc. http://www.lupus.org/webmodules/webarticlesnet/templates/new_empty.aspx?articleid=2847&zoneid=99. Published December 23, 2009. Accessed December 22, 2010.
7. Hänninen, Kaartinen K, Rauma AL, Nenonen M, Törrönen R, Häkkinen AS, Adlercreutz H, Laakso J. Antioxidants in vegan diet and rheumatic disorders. Toxicology. November 2000;155(1-3):45-53.
8. Müller H, de Toledo FW, Resch KL. Fasting followed by vegetarian diet in patients with rheumatoid arthritis: a systematic review. Scand J Rheumatology. 2001;30(1):1-10.
9. McDougall J, Bruce B, Spiller G, Westerdahl J, McDougall M. Effects of a very low-fat vegan diet in subjects with rheumatoid arthritis. Journal Altern Complement Med. 2002;8(1):71-75.
10. Darlington LG, Ramsey NW, Mansfield JR. Placebo controlled, blind study of dietary manipulation therapy in rheumatoid arthritis. Lancet. 1986;1(8475):236-238.
11. McDougall J. The McDougall Program for a Healthy Heart: A Life-Saving Approach to Preventing and Treating Heart Disease. New York: First Plume Printing; 1996.
12. Fuhrman J. Fasting and Eating for Health A Medical Doctor's Program For Conquering Disease. New York: St. Martin's Press; 1995.
13. McDougall J. Star McDougallars. Dr. McDougall's Health and Medical Center. http://www.drmcdougall.com/star.html. Published 2010. Accessed December 29, 2010.
14. Fuhrman J. Success Stories. Dr. Fuhrman For Superior Health and Your Ideal Weight. http://www.drfuhrman.com/success/success.aspx. Accessed December 29, 2010.
15. Heizler-Mendoza A, Desai M. Adopting a Vegetarian Meal Plan: An Option to Consider. Diabetes Self-Management. September-October 2010:28.
16. Sabaté J, Wien M. Vegetarian diets and childhood obesity prevention. American Journal of Clinical Nutrition. March 2010;91(5):1525S-1529S.
17. Craig WJ, Mangels AR. Vegetarian Diets. Journal of the American Dietetic Association. July 2009;109(7):1266-1282.
18. Hajer GR, Haeften TW, Visseren FL. Adipose tissue dysfunction in obesity, diabetes, and vascular diseases. European Heart Journal. 2008;29(24):2959-71.
19. Kim IW, Myung SJ, Do MY, Ryu YM, Kim MJ, Do EJ, Park S, Yoon SM, Ye BD, Byeon JS, Yang SK, Kim JH. Western-style diets induce macrophage infiltration and contribute to colitis-associated carcinogenesis. J Gastroenterol Hepatol. November 2010;25(11):1785-94.
20. Erdelyi I, Levenkova N, Lin EY, Pinto JT, Lipkin M, Quimby FW, Holt PR. Western-style diets induce oxidative stress and dysregulate immune responses in the colon in a mouse model of sporadic colon cancer. J Nutr. November 2009;139(11):2072-8.
21. Simopoulos AP. Evolutionary Aspects of Diet: The Omega-6/Omega-3 Ratio and the Brain. Molecular Neurobiology. Epub 2011 Jan.
22. Cotogni P, Muzio G, Trombetta A, Ranieri VM, Canuto RA. Impact of the omega-3 to omega-6 polyunsaturated fatty acid ratio on cytokine release in human alveolar cells. Journal of parenteral and enteral nutrition. 2011;35(1):114-21. Epub 2011 Jan-Feb.
23. Calder PC. Immunoregulatory and anti-inflammatory effects of n-3 polyunsaturated fatty acids. Braz J Med Biol Res.. April 1998;31(4):467-90.
24. Lock K, Pomerleau J, Causer L, Altmann DR, McKee M. The global burden of disease attributable to low consumption of fruit and vegetables: implications for the global strategy on diet. Bull World Health Organ. 2005;83(2):100-108.
25. Porrini M, Riso P, Oriani G. Spinach and tomato consumption increases lymphocyte DNA resistance to oxidative stress but this is not related to cell carotenoid concentrations. Eur J Nutr. 2002;41:593-599.
26. Crujeiras AB, Parra MD, Rodriguez MC, Martínez de Morentin BE, Martínez JA. A role for fruit content in energy-restricted diets in improving antioxidant status in obese women during weight loss.. Nutrition. 2006;22:593-599.
27. Esposito K, Nappo F, Giugliano F, Giugliano G, Marfella R, Giugliano D. Effect of dietary antioxidants on postprandial endothelial dysfunction induced by a high-fat meal in healthy subjects.. Am J Clin Nutr. 2003;77:139-143.
28. Hermsdorff HH, Zulet MA, Puchau B, Martínez JA. Fruit and vegetable consumption and proinflammatory gene expression from peripheral blood mononuclear cells in young adults: a translational study. Nutrition Metabolism (London). 2010;7:42.
29. Higdon J. An Evidence-Based Approach to Dietary Phytochemicals. New York: Thieme Medical Publishers Inc.; 2007.
30. Auborn KJ, Qi M, Yan XJ, Teichberg S, Chen D, Madaio MP, Chiorazzi N. Lifespan is prolonged in autoimmune-prone (NZB/NZW) F1 mice fed a diet supplemented with indole-3-carbinol. The Journal of Nutrition. November 2003;133(11):3610-3.
31. Velasco P, Francisco M, Moreno DA, Ferreres F, García-Viguera C, Cartea ME. Phytochemical fingerprinting of vegetable Brassica oleracea and Brassica napus by simultaneous identification of glucosinolates and phenolics. Phytochem Anal. 2011;10:1259. Epub 2011 Jan.
32. Verhoeven DT, Verhagen H, Goldbohm RA, van den Brandt PA, van Poppel G. A review of mechanisms underlying anticarcinogenicity by brassica vegetables. Chem Biol Interact. 1997;103(2):79-129.
33. Shapiro TA, Fahey JW, Wade KL, Stephenson KK, Talalay P. Chemoprotective glucosinolates and isothiocyanates of broccoli sprouts: metabolism and excretion in humans. Cancer Epidemiol Biomarkers Prev. 2001;10(5):501-508.
34. Conaway CC, Getahun SM, Liebes LL, Pusateri DJ, Topham DK, Botero-Omary M, Chung FL. Disposition of glucosinolates and sulforaphane in humans after ingestion of steamed and fresh broccoli. Nutr Cancer. 2000;38(2):168-178.
35. Rouzaud G, Young SA, Duncan AJ. Hydrolysis of glucosinolates to isothiocyanates after ingestion of raw or microwaved cabbage by human volunteers. Cancer Epidemiol Biomarkers Prev. 2004;13(1):125-131.
36. Shapiro TA, Fahey JW, Wade KL, Stephenson KK, Talalay P. Human Metabolism and excretion of cancer chemoprotective glucosinolates and isothiocyanates of cruciferous vegetables. Cancer Epidemiol Biomarkers Prev. 1998;7(12):1091-1100.
37. Seow A, Shi CY, Chung FL, Jiao D, Hankin JH, Lee HP, Coetzee GA, Yu MC. Urinary total isothiocyanate (ITC) in a population-based sample of middle-aged and older Chinese in Singapore: relationship with dietary total ITC and glutathione S-transferase M1/T1/P1 genotypes. Cancer Epidemiol Biomarkers Prev. 1998;7(9):775-781.
38. Steinmetz KA, Potter JD. Vegetables, fruit, and cancer prevention: a review. Journal of American Dietetic Association. 1996;96(10):1027-1039.
39. Genkinger JM, Platz EA, Hoffman SC, Comstock GW, Helzlsouer KJ. Fruit, vegetable, and antioxidant intake and all-cause, cancer, and cardiovascular disease mortality in a community dwelling population in Washington County, Maryland. Am J Epidemiol. 2004;160(12):1223-1233.
40. Asten P, Barrett J, Symmons D. Risk of developing certain malignancies is related to duration of immunosuppressive drug exposure in patients with rheumatic diseases. Journal of Rheumatology. August 1999;26(8):1705-14.
41. Lebrun C, Vermersch P, Brassat D, Defer G, Rumbach L, Clavelou P, Debouverie M, de Seze J, Wiertlevsky S, Heinzlef O, Tourbah A, Fromont A, Frenay M. Cancer and multiple sclerosis in the era of disease-modifying treatments. J Neurol. Epub 2011 Feb.