Are There Health Downsides To Vegetarian
Diets?
It's becoming more popular to eat meat-free
at least part of the time.
While more than 3% of Americans are
full-time vegetarians, a recent poll by the Vegetarian Resource Group
found that 37% of respondents say they always or sometimes eat vegetarian meals
when dining out. The top reason? Health.
Although vegetarian eating does have a
stellar health reputation, recent news has focused on what could be bad
about vegetarian diets and more stringent vegan plans, including
reports of hair loss and depression.
So, are there downsides to these supposedly
healthy eating patterns?
"For generally healthy people, I don't
see any reason that eating a vegetarian diet is risky to health," says Qi
Sun, MD, assistant professor of nutrition at the Harvard T.H. Chan School of
Public Health.
However, Sun’s recent research and that of
others strongly suggest that the quality of plant-based food matters when it
comes to health benefits. As in: vegetables, yes; french fries, no.
A vegetarian diet excludes meat, fish, and
poultry always, according to the definition used by the Vegetarian Resource
Group. A vegan plan also doesn't allow dairy products such as milk, eggs,
cheese, as well as animal-based products like gelatin, and followers do not use
other animal products including honey, wool, silk, and leather.
There are potential pitfalls
to meatless eating, Sun says, but nutrition education and using supplements
when needed can help people overcome them.
A Closer Look at Hair Loss
So can giving up meat lead to hair loss? A
recent report found that severe lack of protein, among other diet shortcomings,
can lead to it. That’s because meat contains iron, vitamin B, and zinc, which
are all important for hair growth.
While iron is found in foods like dried beans
and dark green, leafy vegetables, it’s harder to absorb iron from a pure
vegetarian diet, Sun says. However, it is easy to take supplements, he says.
Vegetarians and vegans must take special care to get enough iron. Supplements should
be needed only if they don’t.
Zinc is found in grains, legumes, and nuts.
B12 is in dairy products, eggs, and fortified soy milk and cereals.
Liz Weinandy, a registered dietitian at The
Ohio State University Wexner Medical Center, Columbus, gives nutritional advice
to people on a variety of eating plans
She tells vegetarians and vegans that protein
deficiency can be a hazard, especially for vegans.
But in real life, "I have not had anyone
complain about hair loss on a vegetarian diet," Weinandy says. “It has to
be a protein deficiency going on for a while [to lead to hair loss]."
Vegetarians and vegans can get enough protein
by eating a varied diet with enough calories. For vegans, good protein sources
include soy, quinoa, whole wheat bread, broccoli, peanut butter, beans, kale,
lentils, and almonds. Vegetarians can eat eggs a few times a week, or Greek
yogurt and can be fine, Weinandy says.
People who eat no meat should know about the
risk of low iron, vitamin B, and zinc levels, and be on the alert for symptoms
that may point to a lack of those, Sun says. "The typical zinc deficiency
symptoms include loss of appetite, hair loss, diarrhea, eye and skin lesions,
weight loss, delayed healing of wounds, and taste abnormalities," he says.
But these symptoms may also point to other health issues, he says.
Iron deficiency can cause fatigue, dizziness,
lightheadedness, a fast heart rate, or palpitations, he says.
A range of symptoms may point to low levels
of the various forms of B vitamins. Fatigue and loss of balance, for instance,
could mean a B12 deficiency, Sun says. If you are concerned you may be
deficient, he says, ask your doctor about getting blood tests to check your
levels.
Mood Problems?
Can vegetarian and vegan diets sour your
mood? Research on this is mixed, with some research finding going meatless
improves mood and other studies finding the opposite. In one study of 400 new
mothers, 80 reported postpartum depression. A vegetarian diet was one thing
that seemed to make it more likely to be depressed.
In another study, researchers compared
vegetarians, vegans, and people who eat both plants and animals, and found the
vegans had lower anxiety and stress levels than the meat eaters.
Other researchers looked at mental health
problems in vegetarians and concluded they are more likely to have them, but on
average, the mental problems were there before the people started eating a
vegetarian diet. And they emphasize they found no cause-and-effect link.
Benefits of a Meatless Lifestyle
Some health benefits of eating vegetarian or
vegan are well-documented. Among the most solid perks:
Heart Health
In one recent report, vegetarian and Mediterranean plans were linked with
better heart health.
The quality of the plant-based foods matters,
however, says Sun, citing recent research from Harvard. Researchers tracked
about 200,000 men and women enrolled in several different studies for more than
2 decades.
They assigned positive scores to plant-based
foods and negative ones to animal foods. They scored healthy plant-based foods
such as whole grains higher than unhealthy plant foods, such as french fries.
People who ate healthier plant-based foods
had a 25% lower chance of heart disease, while those who ate unhealthy plant
foods had a 32% higher chance.
Avoiding Diabetes
Several studies have found that vegetarians
are up to 2 times less likely to have type 2 diabetes than non-vegetarians.
In studies comparing vegetarian and
non-vegetarian diets, those on the vegetarian plans had better blood sugar
levels and more weight loss.
Sun and his colleagues found that a diet that
emphasized plant foods and was low in animal foods was linked with about a 20%
lower chance of getting diabetes.
However, when they looked more closely, they
found that diets that emphasized healthy plant foods cut the chance of having
diabetes by 34%, while diets with less healthy plant foods actually raised the
risk of diabetes by 16%.
Healthy plant foods include whole grains,
fruits, vegetables, nuts, legumes, vegetable oils, and tea and coffee. Less
healthy: fruit juices, sweetened beverages, refined grains, pasta, potatoes,
sweets, and desserts.
Caution: Don't Be a Junk Food Vegetarian
While people often view vegan or vegetarian
diets as automatically healthy, that's not so, Sun says. He cautions people not
to become junk food vegetarians.
"If you eat a vegan diet, but eat a lot
of french fries, refined carbs like white bread, white rice," he says,
that's not healthy. Besides avoiding those foods, he suggests ''emphasizing
fruits and vegetables. Not fruit juice but whole food. And nuts."
A meatless plan isn't palatable to everyone,
Ohio State’s Weinandy says. She encourages people to borrow the benefits of
vegan and vegetarian eating, such as eating plenty of fruits and vegetables and
whole grains, to get some health benefits.
As research by Sun and others shows, eating
more healthy plant foods, while not cutting out meat, still has benefits for
heart health and for avoiding diabetes.
Source: WebMD
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