While veganism's draw is clear--ranging from the moral argument against eating animals to the health impact of overconsuming red meat--for many women, one motive is to lose weight. Trade the meat-packed standard American diet for plant-based foods and you'll slim down like you just stepped out of a fat suit. A small percentage of the American population eats animal-free (no eggs, fish, dairy, gelatin, etc.), but the number may be growing as proponents like Michelle Pfeiffer and a dramatically slimmer Bill Clinton praise its virtues. So why have other die-hard vegans like Ginnifer Goodwin and Megan Fox recently defected and (presumably) gone back to ordering medium-rare?
Good in Theory
There's no question that a balanced, well-planned vegan diet can be healthy. "Studies show that vegans have lower BMIs and a reduced risk of heart disease, diabetes, and cancer," notes Vandana Sheth, a Los Angeles--based dietitian and spokesperson for the Academy of Nutrition and Dietetics who frequently works with vegan clients. But is the key. In our weight-loss-obsessed, too-busy-to-plan-meals culture, many women cut out the cheeseburgers (along with fish and skim milk) without considering the nutritional deficit. Between the lack of fresh, quality options in the food deserts of America and the challenges of chowing down in social settings (even in cities like New York, L.A., and Chicago, vegan restaurants are sparse), practitioners may turn to not-so-healthy processed foods like fake cheese and soy patties. "There are some people who may become vegan simply to eat more junk food," says Stella Volpe, R.D., professor and chair of the department of nutrition sciences at Drexel University in Philadelphia. "As a vegan, you need to spend a large part of your life planning what to eat," warns Dr. Michael D. Gershon, chairman of the department of anatomy and cell biology at New York's Columbia University. While it is possible to get the nutrients you need, it's difficult."Vegans are more vulnerable to certain nutritional deficiencies," he says, referring to vitamin B12, omega-3 fatty acids, iron, zinc, calcium, and vitamin D--all critical for, among other things, energy and mood.
That said, whole-food sources of soy, like edamame and tofu, along with legumes and grains like quinoa, can provide plenty of the protein you need. Still, even nutrition professionals find vegan diets hard to regulate. Elite runner and personal chef Devon Crosby Helms, 30, felt "fantastic" for the first six months of her vegan diet. However, because she was already gluten-, bean-, and soy-free (due to allergies), nixing meat was the tipping point to poor health. Suffering from "overwhelming and constant fatigue, muscle loss, and weight gain," Crosby Helms' doctor diagnosed her with hypo-thyroidism, adrenal fatigue, and anemia. With limited food choices, "being vegan created a great deal of anxiety," she says.
Indeed, "totally revamping your diet requires an intense mental adjustment. Any diet that requires you to cut out entire food groups will generally trigger cravings," explains Susan Albers, a clinical psychologist who specializes in eating disorders at the Cleveland Clinic in Cleveland, Ohio. "An extreme diet [of any kind] can often trigger disordered eating and sometimes even an eating disorder." During 26-year-old Pamela Stubbart's final six months as a vegan, the NYC resident experienced blood sugar spikes and intense cravings. "I couldn't focus on anything else but whether or not to eat an egg. It would go on for hours," she says.
For others, going vegan can pay off, initially at least. A vegan for almost two years, Susan Stella Floyd, 33, from Austin, Texas, lost 10 pounds within the first two months. But three months later she regained the weight--and 10 more pounds. She partially blames her "very carb-heavy diet." And while veganism promises healthy cholesterol, Floyd's levels were borderline high. Because a vegan diet may lack appropriate amounts of good fat (like omega-3's and vitamin B12), some vegans may suffer from elevated levels of the amino acid homocysteine (associated with blood vessel damage) and lower HDL (aka good) cholesterol. Both, notes one 2011 study, can actually increase the risk for heart problems and stroke.
Too Much of a Good Thing
After reading books on veganism and working at a health foods store, Bonnie Farrell, 26, from Portland, Maine, figured she was prepared to go vegan. She ate mostly raw foods and also started to bike everywhere. A diet consisting mainly of fruits, veggies, nuts, and seeds, combined with the sudden rigorous exercise, helped her drop 25 pounds. "I took it as a sign that my body was thriving," she says. Instead, the opposite was happening. Her energy levels would skyrocket, only to crash and leave her extremely fatigued. She became consumed by near daily panic attacks. Rounds of testing with two different doctors revealed a deficiency of several vitamins and minerals. Her adrenal system, which regulates stress, had "burnt out"; her thyroid was malfunctioning. "I felt like my body was locked in a prison," Farrell says.
What's going on outside isn't always pretty, either. "Vegan clients have walked into my office with scaly skin because they reduced their fat intake too much," notes Volpe. Dental health may suffer, too. Vitamin deficiencies speed up tooth decay, and overconsumption of carbs produces a highly acidic environment in your mouth, damaging gums and weakening enamel, explains Chicago dentist Dr. Rana Stino. That may explain why after almost two decades sans cavities, Floyd had four. Worse, Farrell was shocked she needed seven fillings--all in one visit. "It was terrifying," she says.
Proceed with Caution
There's no problem with trying veganism, but go in without a game plan and you could put your health in danger. "Meet with a registered dietitian or your doctor first, preferably one who specializes in vegan diets," says Volpe. Then follow up with them if you don't feel right, as they can help make adjustments.
Eventually, Crosby Helms, Stubbart, Floyd, and Farrell all tried eating meat and/or dairy again, this time conscientiously dining on grass-fed, organic fare. "I felt deeply satisfied after my first bite of fried eggs and cheese," says Floyd, who no longer deals with crazy cravings and now has "awesome" cholesterol--which she links, ironically, to a return to eggs and bacon. A year after forgoing veganism, Farrell revisited her doctor. "My thyroid was running normally again, my nervous system was balanced. I felt like myself again. Why didn't I stop sooner?"
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