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The Health Benefits of a Vegetarian Diet - Jane Hart (Alternative and Complementary Therapies 2009)
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64 Increasing research over the past 2 decades has shown that a vegetarian diet may provide important health benefits for individuals who consume such diets. Specifically, a vegetarian diet has been associated with prevention of chronic diseases, including diabetes, heart disease, and obesity. 1–3 Plant foods are rich in vitamins, minerals, fiber, phytochemi- cals, and other compounds that provide antioxidant, anti-in- flammatory, anticarcinogenic, and other properties that con- tribute to disease prevention. In addition to eating an abun- dance of fruits and vegetables that provide these properties, vegetarians also tend to consume less saturated fat and choles- terol and eat fewer calories, compared with nonvegetarians. 3 All of these factors put vegetarians in a good position to op- timize their health and prevent disease. In addition, while re- search papers in the past focused on the potential deficiencies that vegetarians may experience, current research emphasizes the health-promoting benefits of vegetarian diets. is article explores the impact of vegetarian diets on sev- eral chronic conditions. e research presented here represents only a sampling of the current available evidence on the role of the vegetarian diet in chronic disease. Definitions and Demographics Vegetarians are generally defined as people who do not eat meat, poultry, or fish. A vegetarian following a healthy dietary pattern is also a person who eats an abundance of fruits, veg- etables, whole grains, legumes, and nuts; in addition, a veg- etarian may eat eggs, dairy products, and other nutrient-dense foods. A vegan is a vegetarian who does not eat any products of animal origin, such as eggs or dairy products. Vegetarians may be more specifically classified as lactovegetarians (who consume dairy products), lacto-ovovegetarians (who consume dairy products and eggs), or semivegetarians (who eat fish). e American Dietetic Association (ADA) position paper on the vegetarian dietary pattern reported that approximately 2.5% of U.S. adults are vegetarians and < 1% are vegans; 2% of children, ages 6–17, are vegetarians; and ~ 0.5% in this age bracket are vegans. 3 In Canada, it is estimated that 4% of the Canadian adult population is vegetarian. 3 Interestingly, many studies related to vegetarianism note that self-reported veg- etarians often report that they occasionally eat meat, poultry, or fish. Researchers who conducted a survey found that, among 90 self-reported vegetarians, 51 reported eating fish occasion- ally and 14 reported eating poultry occasionally. 4 As experts note, the term vegetarian must be defined care- fully as it may refer to any number of diverse diets (as well as their consumers) beyond the simple concept of not eating ani- mal products. In other words, being a vegetarian does not nec- essarily translate into a healthy diet—a nonconsumer of animal products may still eat foods that are high in fat and/or sugar. One reviewer noted that “a teenager’s brand of vegetarianism can be soda, fries, and macaroni and cheese.” 1 Because diets are diverse, it is important for clinicians to take a full dietary history from any patient who claims to be a vegetarian. e reasons a person may choose to be a vegetarian are moral, environmental, health-related, economic, and faith-based. 3,5 One report stated that younger people (ages 11–20) tend to adopt a vegetarian lifestyle for moral reasons, older people (ages 41–60) tend to be vegetarians predominantly for health reasons, and peo- ple of any age may be vegetarians for faith-based reasons. 5 Reasons why people stop being vegetarian and resume an omnivorous diet can include “not feeling healthy, concern about their nutritional status, a change in living situation, or missing the taste of meat.” 4 DOI: 10.1089/act.2009.15202 • MARY ANN LIEBERT, INC. • VOL. 15 NO. 2 ALTERNATIVE AND COMPLEMENTARY THERAPIES APRIL 2009 The Health Benefits of a Vegetarian Diet Jane Hart, M.D.
Transcript
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Increasing research over the past 2 decades has shown that a vegetarian diet may provide important health benefits for individuals who consume such diets. Specifically, a vegetarian diet has been associated with prevention of chronic diseases, including diabetes, heart disease, and obesity.1–3

Plant foods are rich in vitamins, minerals, fiber, phytochemi-cals, and other compounds that provide antioxidant, anti-in-flammatory, anticarcinogenic, and other properties that con-tribute to disease prevention. In addition to eating an abun-dance of fruits and vegetables that provide these properties, vegetarians also tend to consume less saturated fat and choles-terol and eat fewer calories, compared with nonvegetarians.3 All of these factors put vegetarians in a good position to op-timize their health and prevent disease. In addition, while re-search papers in the past focused on the potential deficiencies that vegetarians may experience, current research emphasizes the health-promoting benefits of vegetarian diets.

This article explores the impact of vegetarian diets on sev-eral chronic conditions. The research presented here represents only a sampling of the current available evidence on the role of the vegetarian diet in chronic disease.

Definitions and Demographics

Vegetarians are generally defined as people who do not eat meat, poultry, or fish. A vegetarian following a healthy dietary pattern is also a person who eats an abundance of fruits, veg-etables, whole grains, legumes, and nuts; in addition, a veg-etarian may eat eggs, dairy products, and other nutrient-dense foods. A vegan is a vegetarian who does not eat any products of animal origin, such as eggs or dairy products. Vegetarians may be more specifically classified as lactovegetarians (who

consume dairy products), lacto-ovovegetarians (who consume dairy products and eggs), or semivegetarians (who eat fish).

The American Dietetic Association (ADA) position paper on the vegetarian dietary pattern reported that approximately 2.5% of U.S. adults are vegetarians and < 1% are vegans; 2% of children, ages 6–17, are vegetarians; and ~ 0.5% in this age bracket are vegans.3 In Canada, it is estimated that 4% of the Canadian adult population is vegetarian.3 Interestingly, many studies related to vegetarianism note that self-reported veg-etarians often report that they occasionally eat meat, poultry, or fish. Researchers who conducted a survey found that, among 90 self-reported vegetarians, 51 reported eating fish occasion-ally and 14 reported eating poultry occasionally.4

As experts note, the term vegetarian must be defined care-fully as it may refer to any number of diverse diets (as well as their consumers) beyond the simple concept of not eating ani-mal products. In other words, being a vegetarian does not nec-essarily translate into a healthy diet—a nonconsumer of animal products may still eat foods that are high in fat and/or sugar. Onereviewernotedthat“ateenager’sbrandofvegetarianismcan be soda, fries, and macaroni and cheese.”1 Because diets are diverse, it is important for clinicians to take a full dietary history from any patient who claims to be a vegetarian.

The reasons a person may choose to be a vegetarian are moral, environmental, health-related, economic, and faith-based.3,5 One report stated that younger people (ages 11–20) tend to adopt a vegetarian lifestyle for moral reasons, older people (ages 41–60) tend to be vegetarians predominantly for health reasons, and peo-ple of any age may be vegetarians for faith-based reasons.5

Reasons why people stop being vegetarian and resume an omnivorous diet can include “not feeling healthy, concern about their nutritional status, a change in living situation, or missing the taste of meat.”4

DOI: 10.1089/act.2009.15202 • MARY ANN LIEBERT, INC. • VOL. 15 NO. 2 ALTERNATIVE AND COMPLEMENTARY THERAPIESAPRIL 2009

The Health Benefits of a Vegetarian Diet

Jane Hart, M.D.

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Research

It is well-known that lifestyle behaviors have a significant im-pact on health and that dietary choices play a critical role in preventing and managing chronic disease. There is a wealth of literature on the health benefits of consuming an abundance of fruits and vegetables, and that literature also makes it clear that a prudent diet is one that contains a balance of fruits, vegetables, legumes, whole grains, nuts, and proteins. Avoidance of satu-rated fat and excess sugar is also a key part of a prudent diet.

There has been increasing research on the health benefits of a vegetarian diet, and that research has shifted from focusing on the potential nutritional inadequacies of such a diet to the benefits of vegetarianism for promoting health and preventing disease. Researchers involved in many of the studies discussed in this article have noted that studying individual nutrients may not be as important as understanding how foods work syner-gistically to promote health and prevent disease. The impact of a vegetarian dietary pattern on chronic disease is increasingly a topic of interest in the literature today, and important emerg-ing research is anticipated in future decades.

DiabetesFamily history and being overweight are two important

risk factors for type 2 diabetes, but increasing evidence sug-gests that dietary patterns can also increase or decrease the risk of developing this condition. A number of studies have shown that vegetarians have a decreased risk for developing type 2 diabetes.

One large study included 8401 cohort members from the Adventist Mortality Study and the Adventist Health Study, who did not have diabetes at baseline and who were followed for 17 years. The researchers found that people who ate meat weekly were 29% more likely to develop type 2 diabetes, com-pared with people who ate no meat.6 The study also revealed that people who adhered to a long-term diet (a 17-year inter-val) of eating meat weekly had a 74% increase in odds of de-veloping type 2 diabetes, compared with people who adhered to a long-term vegetarian diet (in which they ate no meat). The researchers noted that, after controlling for weight and weight change, weekly meat intake was still an important risk factor for type 2 diabetes.

Another study showed that people with type 2 diabetes who followed a low-fat vegan diet improved both glyce-mic control and lipid control.7 Participants were randomly assigned to a low-fat vegan diet or to a diet following the American Diabetic Association guidelines and were evalu-ated at baseline and 22 weeks. At the end of the study, 43% of the vegan-diet group and 26% of the American Diabetic Association–diet group were able to reduce their diabetes medications. Measures of glycemic and lipid control were improved in both groups, but improvements were greater in the vegan-diet group, compared with the American Diabetic Association–diet group. Body weight decreased by 6.5 kg in the vegan-diet group and 3.1 kg in the American Diabetic Association–diet group.

Heart DiseaseA dietary pattern that emphasizes fruits and vegetables and

is lower in saturated fat and cholesterol is advocated by the American Heart Association for lowering the risk of ischemic heart disease.8 A vegetarian diet has also been associated with a lower incidence of, and mortality rate caused by, ischemic heart disease. This association has been largely attributed to the lower total cholesterol levels and lower rates of obesity among vegetarians, compared with nonvegetarians. In addition, the researcherssuggestedthatthevegetarians’higherantioxidantstatus may have been a contributing factor.9

In a review of the influence of diet on coronary heart disease (CHD), one large study, which included 84,251 women and 42,148 men, showed an inverse association between consump-tion of fruits and vegetables—particularly green leafy vegeta-bles and vitamin C–rich fruits—and the risk of CHD.10 In this same review, several studies indicated that higher intake of whole grains as opposed to refined grains was also asso-ciated with a lower risk of developing cardiovascular disease. The review noted that the Indian Heart Study showed that a semivegetarian diet enriched with fruits, vegetables, whole grains, and nuts significantly reduced coronary death and non-fatal myocardial infarction (MI).

An analysis of five prospective studies, which included a large proportion of vegetarians, showed that death from ischemic heart disease was 24% lower in vegetarians, compared with nonvegetarians.11 The researchers reported that subsequent studies have supported these findings and affirmed that lower cholesterol levels and lower rates of obesity among vegetarians contributed largely to these results.

In addition to fruits and vegetables, other components of avegetarian’sdietmaycontributetopreventingheartdisease.Nut consumption, for instance, was associated with a decreased risk of CHD, according to one review.12 This review showed that the risk of CHD was 37% less for people who eat nuts four times per week or more, compared with people who sel-dom eat nuts or who eat no nuts. Eating nuts may also help prevent MI and postpone the development of heart disease by several years, according to the reviewers. Interestingly, these reviewers noted that nonvegetarians may also experience the protection that nuts confer, but that nut consumption is more popular among vegetarians.

Weight ControlOverweight and obesity contribute to numerous chronic dis-

eases, including heart disease, diabetes, and some cancers. Some studies have shown that vegetarians weigh less and have lower body–mass index (BMI), compared with nonvegetarians.

Researchers in a study that compared the effects of popu-lar diets on weight loss and cardiac risk factors found that the effects of the Ornish diet (a vegetarian diet that includes less than 10% of calories from fat) are comparable to the effects of the Atkins, Zone, and Weight Watchers diets.13 Participants who followed the low-fat vegetarian diet for 1 year had modest weight loss (an average of 7.3 pounds). This weight loss was associated with a reduction of total

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cholesterol to high-density lipoprotein (HDL) cholesterol ratio and reductions in C-reactive protein and insulin levels. One obstacle noted in the study was that participants on all of the assigned diets had difficulty in adhering strictly to their diets. Participants who followed their diets strictly had better results.

Another study randomly assigned 64 overweight postmeno-pausal women to a low-fat vegan diet or a control diet based on the National Cholesterol Education Program guidelines. For both groups, there were no limits on portion size or energy intake. The researchers found that, at 14 weeks, women who were assigned to the intervention diet lost an average of 5.8 kg, compared with women assigned to the control diet who lost an average of 3.8 kg.14

A study comparing the weight of omnivores, semivegetar-ians, lactovegetarians, and vegans found that, among 55,459 women from the Swedish Mammography Cohort, 1.73% were semivegetarian, 0.29% were lactovegetarian, and 0.15% were vegan.15 The prevalence of overweight or obesity was 40% among omnivores, 29% among semivegetarians and vegans, and 25% among lactovegetarians. The researchers also found that animal-product intake was not actually zero in any of the self-reported vegetarian categories, including vegans. The researchers stated that differences in body weight and BMI between omnivores and vegetarians may, in part, have resulted

from higher protein and animal-fat intake and lower fiber in-take in omnivores.

CancerA lack of consumption of animal products and lower rates

of obesity among vegetarians may confer benefits for veg-etarians in the area of cancer prevention, but research in this area is still emerging. The ADA position paper on vegetari-anism states that vegetarians have an overall lower cancer rate, compared with the general population, but the associa-tion is less strong when studies are controlled for nondi-etary risk factors.3 There are a number of studies showing no difference between vegetarians and nonvegetarians in in-cidence or mortality from various cancers, including breast and prostate cancer.9,11

A recent prospective study on the role of vegetarianism and isoflavones in risk of developing breast cancer among 37,643 women participating in the European Prospective Investiga-tion into Cancer and Nutrition did not find evidence for a strongassociationbetweenvegetarians’ isoflavone intakeandrisk of breast cancer.16

One review of the health effects of vegetarian diets noted that there is “substantial, although not conclusive, evidence that diets high in red and processed meat are associated with a moderate increase in colorectal cancer risk.”11 The review-

Benefits and Challenges of Being a VegetarianTwo Personal Accounts

Discovering a “New and Healthier Me”

Rhiannon Raeder, a 24-year-old sales support executive in Denver, Colorado, became a vegetarian in the summer of 2008. “I became a vegetarian mainly for the health benefits,” said Ms. Raeder. “I believe, as a vegetarian, I consume less fat and reduce my cholesterol. I am consuming more fruits and vegetables too.” Along with a consistent exercise program, Ms. Raeder reported that her body looks and feels much better since starting her new diet. “I relate the new and healthier me directly to the vegetarian diet,” she stated.

Ms. Raeder’s biggest challenge as a vegetarian has been living with someone who is not a vegetarian. “My boyfriend does try to incorporate a vegetarian lifestyle within his regular diet but it can be difficult,” she said and then added: “Also, going out to restaurants with nonvegetar-ians can be challenging. Fortunately, many restaurants cater to vegetarians, but I still come across a few that do not. Choosing from certain menus can become a difficult task, such as when we go to a steak house!”

And like other people who self-report as being vegetarian, Ms. Raeder said that she does eat fish on occasion—which makes her actually a semivegetarian—because of the health benefits of consuming fish. She said that she has never consulted a health care professional about becoming a vegetarian, adding: “I believe I eat a balanced diet with all the proper nutrients including protein, calcium, and iron.”

Needing “to Be Flexible About What My Body Needs and Wants”

Olivia Schwartz, M.Ed., a 60-year-old counselor in Cleveland, Ohio, was a vegetarian for 15 years and recently resumed eating meat and poultry. Ms. Schwartz originally became a vegetarian for humane concerns regarding animals and perhaps for spiritual reasons as she was deeply involved in a meditation practice at the time she made the switch. Ms. Schwartz believes she was healthy as a meat eater and healthy as a vegetarian but said that she did add more vegetables, fruits, and salads to her diet when she became a vegetarian. She stated that there were some challenges to being a vegetarian: “You have to be creative with foods you prepare so that you do not rely so much on pasta, pasta, pasta! Ordering at restaurants used to be a big challenge, but, over the years, more and more vegetarian items have appeared.”

Ms. Schwartz, like Ms. Raeder, did not seek formal nutritional guidance but said that she probably should have. “I hate tofu and seafood,” she said and then recalled: “I know I ate a lot of dairy products, salads, and fruit, hoping I would get adequate nutrition. I did learn about food combining, did take vitamins for periods of time here and there, and did some worrying about whether or not I was getting enough protein, calcium, iron, etc., but I guess I didn’t worry enough to approach the subject seriously.”

After 15 years of not eating any meat, poultry, or fish, Ms. Schwartz stopped being a vegetarian on her 60th birthday. “It struck me the evening of my birthday that I felt like having a steak and so I did, and it was delicious,” Ms. Schwartz said, and then added: “I need to be flexible about what I feel my body needs and wants, and, at this time, it feels necessary and healthy for me to drop the rigidity around my dietary choices.” She said that she does not know if she will return to being a vegetarian at some point, but added that she felt nourished as a vegetarian and now feels the same way as a meat eater once again.

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ers noted that, in addition to the lack of meat in their diet, vegetarians also have “a lower proportion of secondary bile ac-ids in their feces” and are “less likely to have infrequent bowel movements”—factors that may be protective against colorectal cancer. Further research is needed in this area.

Risk of Nutritional Deficiencies

Today’s literatureonthevegetarian lifestyle is increasinglyfocused on the potential health benefits with the balance of caveats on how to avoid nutritional deficiencies. However, the interplay of nutrients in any diet is complex, and both veg-etarians and nonvegetarians may benefit and incur risks from their dietary choices. The ADA position statement on vegetar-ian diets noted that “appropriately planned vegetarian diets are healthful, nutritionally adequate, and provide health benefits in the prevention and treatment of certain diseases.”3 However, the position paper also described the many nutritional com-plexities of a vegetarian diet and concluded that vegetarians are at risk for various deficiencies, and, depending on individual dietary choices, vegetarians may require more fortified foods and supplements to ensure adequate nutrition.

The authors of the position paper wisely included in their paper the following statement: “Because of the variability of dietary practices among vegetarians, individual assessment of dietary intakes of vegetarians is required.” The authors of this position paper also stated that dietitians play an im-portant role in providing guidance about “food sources of specific nutrients, food purchase and preparation, and any dietary modifications that may be necessary to meet indi-vidual needs.”3

The bottom line is that all diets have potential risks and ben-efits and people should be guided on how to avoid or minimize such risks. Studies have shown that vegetarians who have poor meal planning are more likely to have nutritional deficiencies, compared with people who plan well-balanced meals.17

The need to assess energy requirements and nutritional needs adequately is especially important for infants and chil-dren who are being given a vegetarian diet or whose moth-ers are vegetarian and for pregnant and lactating women. Restrictive or unbalanced diets, such as a fruit-only diet or some macrobiotic diets, may lead to nutritional deficiencies, particularly in growing children, women in the reproductive years, and in pregnant or lactating women, for whom energy demands are higher.3,18 Parents of infants and children who are vegetarians and pregnant and lactating women following a vegetarian diet should be guided by an experienced nutri-tion expert to ensure adequate nutrition.

A vegetarian diet can provide adequate nutrition for infants and children, but the authors of one review on this topic rec-ommend monitoring of the child by a health care professional and adequate meal planning, and noted that supplementation may be required to avoid deficiencies that could lead to serious conditions such as rickets, scurvy, delayed physical and mental development, or even death.18 The reviewers noted that certain

diets, such as vegetarian diets, are more likely to cause prob-lems related to malnutrition in children, compared with adults, becauseofchildren’sgreaternutrientrequirementsrelativeto

body weight. The more rigid the vegetarian diet is, the more difficult it is to guarantee that a growing infant or child is get-ting adequate nutrients.

Commentary

While significant research is emerging regarding the ben-efits of a vegetarian diet, further research is needed to help clarify the role of such a dietary pattern in both the preven-tion and management of disease. What we know for certain is that many of the most common chronic diseases of today are significantly influenced by dietary choices, and, therefore, we must examine the impact of dietary patterns carefully, includ-ing the effects of vegetarian diets, on health and illness.

While, clearly, there are benefits to following a vegetarian di-etary pattern, there are also challenges that must be addressed to make such a diet practical and adequate to meet nutritional needs in children and adult populations. Many of the vegetarian studies showedpeople’sdifficultyinadheringtosuchadietstrictly,andother studies point to the potentially dangerous pitfalls of lacking certain nutrients when following a vegetarian diet.

However, the authors of one study commented that it is pos-sible that the clinical effects of a diet rich in specific fruits and vegetables may be as effective in the prevention and manage-ment of cardiac disease as taking an aspirin per day.19 It would seem wise for every clinician to emphasize the importance and urgency of lifestyle changes utilizing dietary behavior changes that can optimize health, prevent disease, and lower the need for medications.

Conclusion

Most people, regardless of their choice of diets, could use nu-tritional guidance from a professional to ensure that they are con-suming the recommended daily allowances of vitamins, minerals, and other nutrients. All people and their health care providers need to make a concerted effort to increase fruit, vegetable, and whole-grain consumption and reduce intake of saturated fat and sugar. Parents and health care providers must teach children to do so in order to avoid catastrophic health consequences.

“Appropriately planned vegetarian diets provide health benefits

in the prevention and treatment of certain diseases.”

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Finally, it is important to recognize that, with regard to research on vegetarian or any other diets, any study looking at the role of nutrition and diet in health promotion and disease prevention must have long-term follow-up to real-ize the full effects. n

References

1. Panebianco S. The merits and pitfalls of vegetarianism. Explore 2007:3;55–58.2. Sabate J. The contribution of vegetarian diets to health and disease: A para-digm shift? Am J Clin Nutr 2003;78(suppl):502S–507S.3. Mangels AR, Messina V, Melina V, et al. Position of the American Dietetic Association: Vegetarian diets. J Am Diet Assoc 2003;103:748–765.4. Barr SI, ChapmanGE. Perceptions and practices of self-defined current vegetarian, former vegetarian, and nonvegetarian women. J Am Diet Assoc 2002;102:354–360.5.PribisP,GeyerGE,LopezA.Beliefsandattitudes towardvegetarianlifestyles across generations. [abstr 208]. 5th International Congress on Vegetarian Nutrition, Loma Linda, CA, March 4–6, 2008. Online docu-ment at: www.vegetariannutrition.org/5icvn_program.pdf Accessed March 12, 2009.6. Vang A, Singh PN, Lee JW, et al. Meats, processed meats, obesity, weight gain and occurrence of diabetes among adults: Findings from Adventist health studies. Ann Nutr Metab 2008;52:96–104.7. Barnard ND, Cohen J, Jenkins DJ, et al. A low-fat vegan diet improves gly-cemic control and cardiovascular risk factors in a randomized clinical trial in individuals with type 2 diabetes. Diabetes Care 2006;29:1777–1783.8. Lichtenstein AH, Appel LJ, Brands M, et al. Diet and Lifestyle Recom-mendations Revision 2006: A scientific statement from the American Heart Association Nutrition Committee. Circulation 2006;114:82–96.9.GinterE.Vegetariandiets,chronicdiseasesandlongevity.Bratisl Lek Listy 2008;109:463–466.

10. Hu FB, Willett WC. Optimal diets for prevention of coronary artery dis-ease. JAMA 2002;288:2569–2578.11. Key TJ, Appleby PN, Rosell MS. Health effects of vegetarian and vegan diets. Proc Nutr Soc 2006; 65:35–41.12. Kelly JH, Sabate J. Nuts and coronary heart disease: An epidemiological perspective. Br J Nutr 2006;96(suppl)S2:S61–S67.13.DansingerML,GleasonJA,GriffithJL,etal.ComparisonoftheAtkins,Ornish, Weight Watchers, and Zone Diets for weight loss and heart disease risk reduction. JAMA 2005;293:43–53.14. Barnard ND, Scialli AR, Turner-McGrievyGM,etal.Theeffectsofalow-fat, plant based dietary intervention on body weight, metabolism, and insulin sensitivity. Am J Med 2005;118:991–997.15. Newby PK, Tucker KL, Wolk A. Risk of overweight and obesity among semiveg-etarian, lactovegetarian, and vegan women. Am J Clin Nutr 2005;81:1267–1274.16. Travis RC, Allen NE, Appleby PN, et al. A prospective study of vegetarian-ism and isoflavone intake in relation to breast cancer risk in British women. Int J Cancer 2008;122:705–710.17. Leitzmann C. Vegetarian diets: What are the advantages? Forum Nutr 2005;57:147–156.18.DiGenovaT,GuydaH.Infantsandchildrenconsumingatypicaldiets:Vegetarianism and macrobiotics. Paediatr Child Health 2007;12:185–188. 19. Singh RB, Rastogi SS, Verma R, et al. Randomized controlled trial of cardioprotective diet in patients with recent myocardial infarction: Results of one year follow up. Br Med J 1992;304;1015–1019.

Jane Hart, M.D., a board-certified internist, is a clinical instructor and chair of the Committee on Integrative, Complementary and Alternative Medicine at Case Western Reserve University School of Medicine, in Cleveland, Ohio.

To order reprints of this article, e-mail Karen Ballen at: [email protected] or call (914) 740-2100.

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