Nutrition Science and Everyday Application - beta v 0.1

458 ALICE CALLAHAN, PHD, HEATHER LEONARD, MED, RDN, AND TAMBERLY POWELL, MS, RDN
be biased when funded by the supplement industry.
• Most research shows that taking multivitamin/mineral (MVM) supplements doesn’t
result in living longer, slowing cognitive decline, or lowering the chance of getting
cancer, heart disease, or diabetes. However, taking a multivitamin is unlikely to
pose health risks, providing you follow the guidelines below for choosing
supplements. 1
GUIDELINES FOR CHOOSING SUPPLEMENTS
Throughout this text, we have discussed the importance of whole foods. As you might
suspect, supplements can not replace real, whole food. Marion Nestle, professor emerita at
New York University and author of many books about nutrition, wrote eloquently about the
benefits of getting nutrients from food instead of supplements in a 2006 blog post:
“Unless you have been diagnosed with a vitamin or mineral deficiency and need to replenish
that nutrient in a great big hurry, it is always better to get nutrients from foods—the way
nature intended. I can think of three benefits of whole foods as compared to supplements:
(1) you get the full variety of nutrients—vitamins, minerals, antioxidants, etc–in that food, not
just the one nutrient in the supplement;
(2) the amounts of the various nutrients are balanced so they don’t interfere with each other’s
digestion, absorption, or metabolism; and
(3) there is no possibility of harm from taking nutrients from foods (OK. Polar bear liver is an
exception; its level of vitamin A is toxic).
In contrast, high doses of single nutrients not only fail to improve health but also can make
things worse, as has been shown in some clinical trials of the effects of beta-carotene, vitamin
E, and folic acid, for example, on heart disease or cancer. And foods taste a whole lot better,
of course.” 5
However, there are certain populations that might be at risk for developing nutrient
deficiencies, and they may benefit from a MVM supplement or supplements of specific
nutrients. These groups include the elderly, strict vegetarians or vegans, people restricting
their caloric intake, pregnant women, or individuals with food insecurity. 6
If you choose to take supplements, keep moderation in mind, and use the following
guidelines to help you choose a supplement.
1. Don’t substitute for whole foods. According to the 2020 Dietary Guidelines for
Americans, “Because foods provide an array of nutrients and other components that have
benefits for health, nutritional needs should be met primarily through foods.” 7 Whole foods
are complex and not only contain essential vitamins and minerals, but also dietary fiber and
phytochemicals that may have positive health benefits. As their name suggests, supplements
should never act as replacements for whole food, but rather as supplements to fill in some
nutritional gaps.
2. Check the dose carefully. Since dietary supplements are not regulated before they hit
the market, it is not uncommon to find nutrient levels that exceed the upper intake level (UL).
A good rule-of-thumb is to choose a supplement that keeps the dose close to 100% of the
Daily Value (unless advised by a doctor to help correct a deficiency) and definitely no more
than the UL.
3. If getting supplements from multiple sources, make sure you add together the