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Vegetarian DietsIt used to be that scientific
research on vegetarian diets questioned their nutritional adequacy,
particularly with regard to their protein content. But as most of these
concerns have faded in recent years, researchers have begun studying
vegetarian diets with respect to their role in both the prevention and
treatment of disease. As a result, there has been a growing
appreciation for the benefits of vegetarian diets or those that include
generous amounts of plant foods and limited amounts of animal foods. The
American Institute for Cancer Research, the American Cancer Society, and
the National Institutes of Health are some of the many health
organizations now recommending these types of diets. Both the American
Dietetic Association and Dietitians of Canada support appropriately
planned vegetarian diets as "healthful, nutritionally adequate, and
providing health benefits in the prevention and treatment of certain
diseases." Vegetarianism has come a long way ! Technically, a
vegetarian is defined as a person who does not eat meat, fish or fowl or
products that contain them. However, in reality, the eating patterns of
vegetarians can vary considerably, from strict vegetarians (vegans), to
those who include dairy and/or fish in their diet. Some self-described
vegetarians may even include occasional fish, chicken, and meat in their
diet.
Health benefits Much of
what we know about the health benefits of vegetarian diets comes from
studies of Seventh-day Adventists. A high percentage of vegetarians is
found among the adherents of this religious group. Many Seventh-day
Adventists are strict vegans, others merely avoid meat. However,
Seventh-day Adventists, as well as other vegetarians, often have
healthier lifestyles in general, so it's difficult to link the health
benefits of their lifestyle to any single dietary factor, such as the
absence of animal foods. Obesity. Plant-based diets have long
been associated with decreased obesity, which is a risk factor for may
chronic diseases, including heart disease, high blood pressure,
diabetes, and some cancers. Some factors that may help explain lower
body weight in vegetarians include lower fat intake, higher fiber
consumption, and greater consumption of vegetables. Cardiovascular
disease. Numerous studies have shown a decreased incidence of heart
disease among vegetarians compared with nonvegetarians. This may be
explained in part by lower blood cholesterol levels in vegetarians.
Compared to nonvegetarians, lacto-ovo-vegetarians and vegans have blood
cholesterol levels 14 percent and 35 percent lower, respectively.
Although most vegetarians don't eat low-fat diets, their saturated fat
intake is considerably lower than that of nonvegetarians. They also
consume between 50 to 100 percent more fiber, which helps reduce blood
cholesterol levels. In addition, a vegetarian diet has the benefit of
the many phytochemicals found in plant foods that have antioxidant
properties, and antioxidants make blood cholesterol less likely to stick
to artery walls. Hypertension. In addition to having lower
blood pressure in general, vegetarians also have lower rates of
hypertension (high blood pressure) than nonvegetarians. Researchers have
looked at possible explanations for this difference, including lower
body weight, decreased dietary fat, absence of meat or milk protein, or
differences in potassium, magnesium, or calcium intakes, but so far they
have not been able to draw any conclusions. Cancer. Vegetarians
in general have a lower cancer rate compared to the general population.
This difference is most significant for prostate cancer and colorectal
cancer. A number of factors in vegetarian diets may affect cancer risk,
such as lower fat consumption, more fiber, more fruits and vegetables,
lower levels of heme iron (from animal sources) and higher intake of
phytochemicals like isoflavones, hormonelike plant compounds found in
soy and other plant foods. Diabetes. There is some evidence
that vegetarians have lower rates of diabetes. this protective effect
may be the result of lower body weight among vegetarians, as well as a
higher fiber intake, which can both improve blood sugar control.
Children's needs
Children have high nutrient requirements, but they have small stomachs,
so a strict vegetarian diet, containing mainly fruits and vegetables,
whole grains, and a lot of bulky fiber, may be too low in calories and
nutrients to meet a child's needs. But with some careful planning, a
balanced vegan diet with good sources of protein and some concentrated
sources of energy can adequately support growth and nutrition. The
daily diet should include: three meals plus plenty of appealing snacks
like trail mix, muffins, and whole-grain cookies; sources of fat, such
as nuts, seeds, avocados, and nut-butters; and plenty of protein-rich
foods like tofu, nut-butters, soy cheese, and yogurt.
Vegetarians may need more iron and zinc
Phytates, compounds found mostly in cereal grains, legumes, and nuts,
bind with iron and prevent the body from using it. Vegetarians should
increase their intake of plant foods that are rich in iron, or should
discuss the use of an iron supplement with their doctor. The Recommended
Dietary Allowance (RDA) of iron for vegetarians who eat no animal
products is 1.8 times greater than the RDA for nonvegetarians. For
example, a 30-year-old vegetarian woman will need 32 mg instead of 18 mg
daily. Vitamin C can help reduce the effects of phytates, and cooking or
baking vegetables also releases some of the iron that is bound to the
phytates. |