The lament comes from my friend Shelly, but
it could've come from thousands of other women: "I know my diet isn't perfect,"
says Shelly. "But between my family (including a newborn), my work and my
running, I just feel tired a lot. I don't know, maybe there's something
missing in my diet that would give me the energy I used to have."
Busy women like Shelly often find themselves skipping meals, eating "empty"
snacks, skimping on vitamins and overstuffing with fat-free foods. Women
also have to realize that what works for men may not work for them. We have
different nutritional requirements.
To help you meet those requirements, here are eight nutrition tips. Follow
them, and your stamina and performance should improve, plus you'll be getting
the nutrients you need to fight the chronic diseases that are of increasing
concern to women.
Take it from me, eating frequently during the
day is good for you. Research shows that women who keep their weight steady
are usually those who eat at least four times a day and who don't skip meals.
This "grazing" may improve your work performance, too, as one study of men
and women showed that eating a snack of a few hundred calories in the afternoon
improved memory and cognitive skills later in the day.
On the other hand, skipping meals can leave you feeling drained, unable
to concentrate and lackluster about your evening workout. Also, missing
meals earlier in the day often leads to overeating in the afternoon and
evening. At that point, you'll be more likely to select foods that are high
in fat, sugar and calories.
Try to eat around five times a day--that's three meals and two snacks. If
you have a busy schedule, you'll need to plan ahead. Get in the habit of
stowing snacks in your workout bag, or bring healthful munchies to work
for midmorning and midafternoon snacking. Dried fruit, energy bars, canned
vegetable juice and small boxes of ready-to-eat breakfast cereal are all
good choices that are high in carbohydrates, fiber, vitamins and minerals.
Vitamin B2, or riboflavin, assists in the breakdown
of carbohydrates and fats for energy for working muscles. It's no surprise,
therefore, that this vitamin plays a crucial role during endurance exercise.
Because research on women shows that 30 minutes of daily exercise lowers
riboflavin levels in the body, you should try to get at least the RDA (1.3
milligrams for women). You might want to talk to your doctor about whether
or not you need more than the RDA, especially if you do high-mileage training.
Most dairy products are good sources of riboflavin. Go for 1 percent or
skim milk, nonfat yogurt or other low-fat dairy foods. Breads, cereals and
other grain products are also good sources.
Getting enough calcium and protein is particularly
crucial for women, who are susceptible to osteoporosis. Though activities
such as running and weight training help build stronger bones, if you are
amenorrheic (you frequently miss your menstrual period), you can lose bone
mass despite regular exercise. That's because amenorrheic women have lower
levels of estrogen, a hormone that plays a key role in building and maintaining
bone calcium.
An estimated 25 percent of women runners become amenorrheic at some point.
Some are helped only by estrogen-replacement therapy. In other cases, a
simple dietary change does the trick--especially if you've been skimping
on calcium and protein.
Research suggests that the calcium RDA of 800 milligrams for women over
the age of 24 is insufficient, particularly for amenorrheic athletes. Around
1,200 milligrams, the equivalent of four servings of milk, looks to be more
appropriate. As for protein, women vegetarians should know that a low intake
may put them at higher risk for amenorrhea.
So be sure you get regular servings of dairy products, calcium-rich tofu
and greens, and calcium-fortified orange juice. Also, eat lean meat and/or
high-quality protein combinations such as pinto beans and rice. Avoid fiber
supplements: these bind calcium and other minerals in the intestinal tract,
thus decreasing the absorption of essential nutrients.
Many women have found that being a vegetarian
is a good way to reduce fat intake, boost carbohydrate intake and improve
health. Further, research shows that vegetarians are generally healthier
than meat-eaters, that they have a lower incidence of cancer and heart disease
and that they have leaner bodies.
But being a vegetarian doesn't guarantee improved health. A recent study
of vegetarian women showed that compared to nonvegetarians, they took in
less calcium, zinc and vitamin B12. Those in the study ate less than half
the RDA for B12, a vitamin crucial for healthy red blood cells and nerve
fibers. Since B12 is found only in animal products (red meat, fish, shellfish,
eggs and milk are good sources) strict vegetarians (or "vegans") must look
for foods, such as soy milk, that are fortified with this vitamin.
Zinc, which is needed for a strong immune system, is found almost exclusively
in meat (oysters are an especially rich source). An exception is whole grains
(once they get refined they lose their zinc content). Wheat germ is one
of the best zinc sources; add a tablespoon or two to hot cereals, casseroles,
soups or blender drinks.
Green, leafy vegetables such as broccoli, kale
and certain dark-green lettuces are loaded with folate, another B vitamin.
Most women don't get enough of this vitamin, and the deficiency is linked
to severe neural-tube defects in newborns. This connection is so strong
that the Centers for Disease Control and Prevention and the U.S. Food and
Drug Administration now recommend that women take in 400 micrograms of folate
daily, which is more than twice the current RDA. There's also talk by the
FDA of fortifying grains with folate (as is already done with the B vitamins
thiamine, riboflavin and niacin). Adding folate to breads and pastas would
boost folate intake by an estimated 30 to 70 percent.
Until this happens, try to eat good sources of folate daily. In addition
to leafy greens, citrus fruits are also high in this vitamin. A 6-ounce
glass of orange juice contains 120 micrograms of folate.
One of every two women will die of cardiovascular
disease. And although women on average are a decade older than men when
the disease first strikes, it kills as many women as it does men. (Ten times
more women die of heart disease than die of breast cancer each year.)
Fortunately, research has shown that people who eat regular servings of
soybean products such as tofu and miso are at a lower risk of heart disease.
Soybeans contain substances called phytoestrogens, which research has shown
can significantly lower "bad" LDL cholesterol and raise "good" HDL cholesterol.
Add soybeans to soups and casseroles as you would other dried beans. Tofu
works well in salads, pasta dishes and sandwiches. And though soybeans are
somewhat higher in fat than other beans, that fat is primarily the cholesterol-lowering
monounsaturated and polyunsaturated types.
Studies show that more than 50 percent of all
women runners are deficient in iron. Sagging iron levels result in fatigue
and poor endurance, since the blood is unable to carry oxygen as efficiently
to working muscles. Feeling chilled or cold may be another sign that iron
is low. Though losses of this important mineral occur during menstruation
and in a few other small ways, lack of iron in the diet is the most likely
cause of deficiency, as studies show that women distance runners usually
get less than the RDA of 15 milligrams.
The solution is simple: eat more iron-rich foods. Lean red meat and dark
poultry are two of the best sources, in part because the form of iron they
contain is easy to absorb. Women often shy away from red meat due to its
fat content, but by choosing lean cuts you can get your iron while still
maintaining a low-fat diet. Two good nonmeat sources are lentils and iron-fortified
breakfast cereals. Another point to remember: the tannins that are in coffee
and tea block iron uptake from food, so drink these beverages between meals,
not with them.
Before turning to supplementation as your source, check with your doctor.
Too much iron has its drawbacks: it can limit the absorption of zinc and
may also cause constipation. Better to increase your iron intake with 2
to 4 ounces of lean meat a day.
Thousands of fat-free and reduced-fat products
have hit the market in recent years. But this fat-free frenzy has a downside.
Many people think that because a food is fat-free they can eat as much of
it as they want. Not true. Fat-free doesn't mean calorie-free. Many of these
foods are loaded with sugar and calories, so gorging on them will cause
weight gain.
Loading up on fat-free goodies may also starve you of important vitamins
and minerals, since many fat-free products are refined and therefore low
in key nutrients. Many are also lower in fat-soluble nutrients such as vitamin
E, an antioxidant that protects against age-related diseases. Research shows
that women who switch to a low-fat diet (less than 30 percent fat calories)
often fall below their requirement for vitamin E.
To beat the fat-free nutrition blues, make sure you're getting several servings
of fresh fruits and vegetables a day. To get your vitamin E, eat plenty
of whole grains, and try to use small amounts of vitamin E-rich oils, such
as corn oil or walnut oil, for cooking or on salads. Check food labels for
calorie amounts even when you're buying fat-free foods. And remember, if
it's weight loss you're after, you simply need to take in fewer calories
than you burn.
References
Liz Applegate, Ph.D., is the Nutrition Editor
for Runner's World. She is a member of The National Triathlon Training Camp
Elite Team, and teaches at the University of California at Davis.
