In addition to nutritional concerns, there is some
evidence that vegan diets may actually increase the
risk of breast cancer in women, particularly in those
who use large amounts of soy-based products. Soy-
beans contain phytoestrogens, or plant estrogens,
which have been implicated in breast cancer. The
plant estrogens in soy-based products may also
explain why committed vegans have a disproportion-
ate number of female babies, and why these girls have
a higher rate of precocious puberty than girls born to
nonvegetarian mothers.
Research and general acceptance
Studies of the role of vegetarian diets of all types
in preventing disease go back to the 1960s, when the
National Institutes of Health (NIH) and the National
Cancer Institute (NCI) began to study members of the
Seventh-day Adventist Church. NIH findings indicate
that Adventist men live on average seven years longer
than men in the general population, and Adventist
women eight years longer than their non-Adventist
counterparts.
Studies of vegans as a subpopulation of vegeta-
rians are fewer in number than those of less strict
vegetarians; however, the emphasis in medical
research has shifted in the early 2000s from concern
about nutritional deficiencies in people following these
diets to the role of plant-based diets in preventing or
treating chronic diseases. In this regard vegan diets
and lifestyles appear to be beneficial. One 2005 study
of 64 overweight postmenopausal women found that a
vegan diet brought about a significant weight loss and
improved insulin sensitivity (an important factor in
evaluating the patient’s risk of developing type 2 dia-
betes), despite the lack of prescribed limits on food
portion size or calorie intake. Two studies published in
2004 comparing a group of overweight adults on a
vegan diet with a control group following a National
Cholesterol Education Program Step II Diet showed
that the low-fat vegan diet was as acceptable to the
subjects as the Step II diet, and was equally effective in
promoting weight loss. Those on the vegan diet, how-
ever, told the researchers that the vegan diet was
harder to prepare than their normal meals.
In terms of general acceptance, vegan diets differ
from less strict vegetarian regimens in being more
difficult to follow and in causing more social friction
with nonvegans. Some vegetarians who are not vegans
have noted that evaluating foods, clothing, cosmetics,
and other items as not containing animal products
often requires considerable knowledge of production
methods as well as the derivation of the ingredients. In
addition, such items as vitamins,dietary supplements,
and prescription medications may be processed using
non-vegan ingredients (gelatin for capsules, glycerin in
some liquid medications), and these are not always
listed on the packaging. The complications of replac-
ing animal-derived ingredients in some recipes and the
difficulty of finding restaurants offering dishes accept-
able to vegans also contribute to a widespread percep-
tion of veganism as a potentially problematic lifestyle.Resources
BOOKS
Harris, William, MD.The Scientific Basis of Vegetarianism.
Honolulu, HI: Hawaii Health Publishers, 1995.
Stepaniak, Joanne.The Vegan Sourcebook, 2nd ed., with
nutrition section by Virginia Messina. Los Angeles:
Lowell House, 2000.
Stuart, Tristan.The Bloodless Revolution: A Cultural History
of Vegetarianism from 1600 to Modern Times. New
York: W. W. Norton & Co., 2006.
VEGAN COOKBOOKS
Piekarski, Ro, and Joanna Piekarski.Everybody’s Vegan
Cookbook. Buckingham, VA: Integral Yoga Publica-
tions, 2003.
Raymond, Carole.Student’s Go Vegan Cookbook: Over 135
Quick, Easy, Cheap, and Tasty Vegan Recipes. New
York: Three Rivers Press, 2006.
Sass, Lorna J.The New Vegan Cookbook: Innovative Vege-
tarian Recipes Free of Dairy, Eggs, and Cholesterol. San
Francisco: Chronicle Books, 2001.
Tucker, Eric.The Artful Vegan: Fresh Flavors from the Mil-
lennium Restaurant. Berkeley, CA: Ten Speed Press, 2003.
Wasserman, Debra, and Reed Mangels, PhD, RD.Simply
Vegan: Quick Vegetarian Meals, Vegan Nutrition, and
Cruelty-Free Shopping, 4th ed. Baltimore, MD: Vege-
tarian Resource Group, 2006.
PERIODICALS
American Dietetic Association and Dietitians of Canada.
‘‘Position of the American Dietetic Association and
Dietitians of Canada: Vegetarian Diets.’’CanadianQUESTIONS TO ASK YOUR
DOCTOR Have you ever supervised a patient on a vegan
diet?
What is your opinion of veganism compared to
less strict forms of vegetarianism?
Do you agree with the ADA and Institute of
Medicine guidelines?
Have you ever treated a patient with a health
problem related to a calcium or vitamin B 12
deficiency from following a vegan diet?Veganism