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Vitamins & Minerals
Will a supplement give you more
energy?
Vitamins and minerals are essential
compounds needed in small amounts by the body. Contrary to popular
belief, taking vitamin and mineral supplements will NOT give you
energy. Only calories (from carbohydrate, protein, and fat) give you
energy. Vitamins and minerals have no calories, so they can’t give
you energy. Vitamins and minerals do, however, play vital roles in
the metabolic processes that convert carbohydrate, protein, and fat
to energy. So, if you have a deficiency of a certain vitamin or
mineral, taking a supplement may help make you feel better.
Read on to learn…
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From A to Zinc: What does each
vitamin and mineral do for your body.
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Best food sources to get the levels
you need.
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Whether or not you need a
multivitamin and mineral supplement.
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Tips for choosing a quality product.
Vitamins
Vitamins can be classified into two categories: fat-soluble vitamins
(which include vitamins A, D, E, and K) and water-soluble vitamins
(which include vitamin C and six B vitamins -- thiamin, riboflavin,
niacin, B6, folate, and B12).
Click here (From A to Zinc) for a listing of each vitamin's major
functions, food sources, recommended dietary allowance (RDA), and
upper limit (UL) for safe supplementation.
Minerals
Minerals can also be classified into two categories: major minerals
(which include calcium, phosphorus, magnesium, sodium, and
potassium) and trace minerals (which include iron, zinc, iodine,
chromium, and selenium).
Click here (From A to Zinc) for a listing of each mineral’s major
functions, food sources, recommended dietary allowance (RDA), and
upper limit (UL) for safe supplementation.
Do you need a supplement?
If you are a healthy individual who usually eats an optimal diet
(with enough calories and enough servings from all the food groups),
it is possible for you to get everything you need without a
supplement. If you regularly eat a fortified breakfast cereal or
other fortified products (like sports bars or shakes), it’s even
easier. Many of these foods supply 30-100% of the Daily Value for
many nutrients. Still, most health professionals recommend that all
adults take a multivitamin and mineral supplement since the
potential benefits far outweigh the risks.
Read on to learn…
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How foods can meet all of your vitamin and mineral needs.
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Who may need to take a supplement.
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How to choose the right multi for you.
The Food Guide Pyramid: A great guide for assuring adequate nutrient
intake
The Food Pyramid separates foods into 6 groups. Each group provides
a distinct array of different nutrients. Check it out…
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Grains: Supply lots of complex carbohydrates, fiber, some protein,
plus B vitamins 1, 2, and 3 (thiamin, riboflavin, and niacin), as
well as the minerals magnesium and iron.
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Vegetables and fruits: Supply carbohydrate, fiber, vitamins A and
C, folate, potassium, and magnesium. Green leafy vegetables are also
good sources of vitamin K, iron, and calcium.
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Milk products: Supply protein and carbohydrate, plus calcium,
riboflavin, vitamin B12 and (if they are fortified) vitamins A and
D.
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Meat, poultry, fish, legumes/beans, eggs, and nuts: Supply
protein, phosphorus, vitamin B6 and 12, iron, zinc, magnesium,
niacin, and thiamin.
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Vegetable Oils: Supply essential fatty acids and vitamin E.
Who might not be getting enough from each of these food groups?
There are many situations in which students might not be getting
enough servings from all of the food groups to meet their nutrient
needs. Below are some examples:
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Students who are strict vegetarians.
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Students who are allergic or intolerant to certain foods (like
milk or wheat).
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Students who are restricting their calorie intake to lose weight
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Students who are following a rigid fad diet that does not include
certain foods or food groups.
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Students who don’t choose an optimal diet on a regular basis.
In each of these cases, a supplement may be a good idea. The hard
part is how to choose the right one.
Ten tips for choosing a multi
So, you've decided to take vitamin and mineral supplements. How do
you filter through all the products out there and choose the best
one (or ones) for you? Here are some suggestions:
1. Keep it simple. Choose one single multi vitamin and mineral
supplement vs. many separate individual tablets.
In general, nutrients are absorbed best from foods, in the presence
of other nutrients that favor their absorption. Taken in pure
concentrated form, high amounts of individual nutrients can
interfere with the absorption of other nutrients. For example, zinc
hinders copper absorption, iron hinders zinc, calcium hinders iron,
very high levels of beta-carotene may interfere with the absorption
of other disease-fighting carotenoids, and so on.
The same it true of amino acid supplements. Amino acids compete with
one another for absorption. When you eat protein-rich foods, you
consume all the amino acids together in the right proportion. If you
take high doses of single amino acids, however, you may be
interfering with the absorption of other amino acids and thus
impairing protein synthesis. That’s why it’s better to get nutrients
from whole food sources when possible.
To get the right proportion of different nutrients and to minimize
adverse interactions, choose one simple multi. You'll save yourself
a lot of money and also the trouble of having to remember to take
lots of pills!
2. Avoid excesses. Choose a multi that supplies nutrients in amounts
smaller than, equal to, or very close to 100% of the recommended
Daily Value (DV).
Remember, this is a supplement. You may already be getting close to
(or more than) 100% of most vitamins and minerals from the foods in
your diet. In most cases, there is no need to supplement with more
than 100% unless specifically recommended by a health care
professional.
Some students think that if a little of something is good, more must
be better. This is NOT TRUE! Megadoses of certain vitamins and most
minerals are harmful and can result in toxic reactions. It’s not
possible to reach toxic doses through eating whole foods. But it is
definitely possible to reach toxic doses with supplements.
Check out the examples below:
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Too much vitamin A from retinol (often called vitamin A palmitate
or acetate) has been linked with a higher risk of hip fractures.
Beta carotene, which the body converts to vitamin A, is not
associated with this risk.
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Too much vitamin B6 (which a lot of women might be taking for its
purported PMS benefits) can lead to neurological damage.
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Too much iron can impair calcium and zinc absorption, contribute
to constipation, may increase the risk for heart disease, and can be
toxic for students with hemochromatosis (a genetic defect that
causes iron overload).
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Too much zinc (which a lot of students may take to fight off
colds) may actually depress immune function and lower the "good
cholesterol" in your blood.
Some formulas may supply more than 100% DV of some nutrients. This
is okay so long as a daily dose does not exceed the upper limit (UL)
for any nutrient. The UL is the level above which toxic effects may
occur. See
From A to Zinc for a listing of all the vitamins' and
minerals' upper limits.
3. Keep in mind that women need more iron than men.
The Daily Values are based on the highest needs of any sex and age
group. While the needs of most nutrients are similar for both men
and women, iron needs are significantly different. Women lose a lot
of iron with their monthly menstrual cycles, and as a result, they
are at much higher risk for iron deficiency. Women should look for a
multi with 100% of the DV for iron (18 mg). But, men (and
postmenopausal women) should look for a special “Men’s” or
“Senior’s” formula that has 0-8 mg of iron.
4. Consider a separate supplement for calcium if your diet is
lacking.
Most multis don’t contain enough of this mineral because it is too
big and bulky to fit into a single pill. If you don’t consume at
least three calcium-rich foods daily (e.g. milk foods or
calcium-fortified products), you probably need to take a separate
calcium supplement. Click here for more info about
calcium.
5. Consider higher doses of antioxidants from foods and/or a
supplement.
What are antioxidants?
Antioxidants are substances that protect the body from oxidative
damage (toxic reactions with oxygen). Oxygen is vital to life, but
at the same time, it has the potential to cause a lot of damage in
the body. Oxygen can react with cell membranes, genetic material,
and other body compounds to form very unstable molecules called
“free radicals.” Left unchecked, these free radicals exert a
domino-like effect in the body, as each reacts with other compounds
to become more stable. Over time, high amounts of oxidative damage
may contribute to aging, heart disease, cancer, as well as other
degenerative diseases.
Antioxidants are protective because they get oxidized themselves so
that the body's cells and tissues are spared. In a way, antioxidants
are like bodyguards; they jump in front of the bullet to protect the
person they are guarding from harm.
Our bodies have their own antioxidant defense systems to protect
themselves from the constant influx of oxygen we breathe everyday.
These natural defense systems may weaken with age or they may get
stronger with regular physical activity. Certain vitamins and
minerals in our diet can also serve as antioxidants. For example,
vitamin C, vitamin E, and selenium all protect our bodies from
oxidative damage. Many phytonutrients (plant chemicals with
disease-fighting properties) also perform antioxidant functions.
Phytonutrients include carotenoids (such as beta carotene in
carrots, lycopene in tomatoes, and lutein in leafy greens) and
flavonoids (such as catechins in green tea).
How much of these substances offers optimal protection?
Some experts believe that antioxidants in higher amounts than the
RDA (Recommended Dietary Allowance) may be beneficial.
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Vitamin C RDA = 75 mg for women, 90 mg for men (an extra 35 mg if
you smoke); but several experts recommend 200-500 mg to saturate
your body.
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Vitamin E RDA = about 30 IU; but several experts recommend 100-400
IU.
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Beta Carotene: There is no RDA or specific recommendation.
However, the RDA for vitamin A is 2300-3000 IU for women and men
respectively, and beta carotene can be converted to vitamin A in the
body.
Should you supplement with these?
It’s actually fairly easy to get the higher amounts of beta carotene
and vitamin C from foods. Consider the following points:
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One 8 oz. glass of orange juice has about 100 mg of vitamin C. Add
just two more ½ cup servings of vitamin C-rich fruits and vegetables
(like broccoli, sweet red bell pepper, chili peppers, citrus fruits,
kiwi, berries, or melon) and you’re at your goal of 200-300 mg for
the day.
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Just 3/4 cup cooked carrots provides 15,875 IU of beta carotene
(which can be converted to 2643 IU, or 100% of the RDA for vitamin
A). Other deep orange, yellow, or red colored fruits and vegetables
and dark leafy greens are also rich sources of beta carotene.
On the other hand, it’s much more difficult to get the higher
amounts of vitamin E from food sources alone.
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Vitamin E is found in high amounts in vegetable oils, nuts, seeds,
and wheat germ.
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But, you would have to consume 6 cups of canola oil or 3.5 cups of
shelled sunflower seeds to get 400 IU of vitamin E.
Bottom Line:
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It may be reasonable to take a separate vitamin E supplement (and
vitamin C if you are not eating several servings of fruit and
vegetables every day).
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Don’t exceed the upper limit of 2000 mg for vitamin C or about
1200 IU for vitamin E. Harmful effects can occur beyond these
limits.
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Rely on food for beta carotene and other phytonutrients.
Supplements of beta carotene have been linked with increased risk of
lung cancer in one recent study with smokers. High doses may
interfere with other disease-fighting carotenoids found in whole
foods.
6. Look for a supplement with the “USP” or “NSF” seal of approval.
Or consult
Consumer Lab for a listing of quality products. Supplements may or may not be packaged in a capsule that will
dissolve in your body. And, they may or may not contain the stated
ingredients on the label. If a label says “USP” or “NSF,” the
supplement has undergone and passed extensive quality testing by the
United States Pharmacopeia or NSF International (both
not-for-profit, non-governmental organizations).
The USP and NSF quality testing ensures the following:
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Disintegration (how fast a tablet breaks down into small pieces or
at least into a mushy mass so that its ingredients can proceed to
dissolve).
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Strength or potency (whether the amount of the vitamin or mineral
in the tablet actually is the amount claimed on the label)
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Purity (the pill hasn’t degraded during production or been
contaminated by bacteria, heavy metals, or other undesirable
substances). NOTE: The dissolution test does not apply to supplements that are
“sustained-release” or “timed-release,” only immediate release.
7. Don’t be fooled by marketing ploys.
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Statements like “release-assured,” “laboratory-tested,” “quality
and potency guaranteed,” and “scientifically blended” carry little,
if any, legal weight if not accompanied by the USP or NSF seal.
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In most cases, “natural” vitamins are no better than synthetic.
The one exception is natural vitamin E (d-alpha tocopherol), which
appears to be slightly better retained and used by the body than
synthetic E (dl-alpha tocopherol). By contrast, folic acid
(synthetic form) is more bioavailable than folate (the natural form
found in foods).
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In theory, “chelated” minerals may be better absorbed. Because
they are sitting inside an amino acid “claw,” they are protected
from substances in foods that can bind them. But, it may not be
worth the extra cost. Chelated calcium, for example, is absorbed
only 5-10% better than ordinary calcium, but it costs five times as
much.
8. Be sure to check the expiration date.
9. Take it on a full stomach.
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Some nutrients are better absorbed when your digestive tract is
geared up to handle food. Also, food slows the movement of the
nutrients through the digestive tract, allowing more time for them
to dissolve and be absorbed.
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Unless your doctor or pharmacist says otherwise, it’s a good rule
of thumb to wait a few hours between taking any prescription
medication and taking a multi, since some nutrients could interfere
with the drug, and vice versa.
10. Put your supplement in perspective. Some students believe “I don’t need to worry about how I eat, I took
my supplements this morning.” Taking supplements does not make up
for a lousy diet. Supplements can’t cancel out the damaging effect
of a fast food diet high in saturated fat and sodium. And, they
aren’t packaged with fiber and the disease-fighting phytonutrients
that only plant foods (like vegetables, fruits, whole grains, nuts,
and beans) provide. In addition, they are not the magical cure to
sleep deprivation, lack of exercise, and excessive stress. Most of
the time, aim to eat like the Food Pyramid and supplement a healthy
lifestyle with a multi.
Sheri Barke, MPH, RD
COC, Student Health & Wellness Center
Rev. 2005
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