When it comes to taking your vitamins, minerals, fish oils, probiotics, and other supplements, you have questions. Lots of them! What’s the best time of day to take them? Can you take them all at once? What’s the best place to store them? And the list goes on. We heard you. We turned to Tieraona Low Dog, MD, author of Fortify Your Life: Your Guide to Vitamins, Minerals, and More, for answers to some of your most common queries.
Q: How can I make sure that I’m buying a quality supplement?
Dr. Low Dog: Stick with reputable brands manufactured in the U.S. Most of the really disturbing news about “supplements” is not about vitamins, minerals, or common nutritional supplements, which generally contain what they claim on their labels. Steer clear of herbal products coming out of China and India that have been found on numerous occasions to be adulterated with undeclared prescription drugs, as well as high levels of lead, mercury, and/or arsenic.
Also, look for third-party seals such as The United States Pharmacopeia, a scientific nonprofit organization that sets standards for the identity, strength, quality, and purity of dietary supplements manufactured, distributed, and consumed worldwide; NSF International, an independent organization of scientists and public health experts that sets standards for supplements and tests and certifies them; and Consumer Labs, a private company that tests numerous branded products and allows companies that pass its quality tests to use its seal.
Q: How do I know if a manufacturer’s claims about a supplement are accurate?
Dr. Low Dog: The Food and Drug Administration (FDA) has strict rules about what companies can say about supplements. Manufacturers can claim that a supplement supports general well-being or the normal structure or function of the human body. For instance, such statements as “Calcium builds strong bones” or “Antioxidants maintain cell integrity” are permitted. However, labels (and advertisements) cannot claim that a supplement treats or cures diseases. So, while there are randomized controlled trials that demonstrate that the herb St. John’s wort is effective for the treatment of depression, for example, a manufacturer cannot say this on the label. Instead, the label would have to say something like, “St. John’s wort supports a healthy mood.”
Q: It seems like recommended supplement dosages range everywhere from minimum daily values to mega-doses. How do I know what’s right for me?
Dr. Low Dog: Figuring out how much of a certain supplement you should take is important, regardless of the manufacturer’s recommendations. When it comes to vitamins and minerals, we have a pretty good idea about how much is needed to prevent disease. Most of us, however, would like to do more than just prevent rickets or beriberi; we would like to experience vitality and health. But just as important, you’ll want to make sure that you aren’t taking too much of any particular ingredient or nutrient. You must take into account your age, gender, diet, and a host of other factors.
The daily value (DV) is a percentage, calculated on the average recommended daily allowance (RDA) for adults. For each nutrient, there is only one DV for everyone 4 years of age or older. That means the DV does not distinguish between the nutritional needs of an 80-year-old man, a 29-year-old woman, or a 6-year-old child. Be aware that your RDA might be higher or lower than the DV. For example, the DV for vitamin D is 400 IU, whereas the RDA for anyone from 12 months to 70 years of age is 600 IU—and 800 IU if you’re over the age of 70. All vitamins will list 400 IU as 100 percent of the DV; however, just as an example of how general the DV is, a 75-year-old man would actually need double that amount.
What you won’t find on labels is information about the upper limit (UL), which is the tolerable upper intake level for a given nutrient. In other words, the UL is the highest daily intake of a nutrient unlikely to pose a risk of adverse health effects to most people, as determined by the Food and Nutrition Board. The UL represents total intake of a vitamin or mineral from food, beverages, and supplements, and differs for infants, children, teenagers, men, and women of all ages, as well as pregnant and nursing women. For a chart detailing the upper intake levels of vitamins and minerals, visit The National Institutes of Health website (nih.gov), or refer to my book, Fortify Your Life.
Q: Supplements come in so many forms—tablets, capsules, softgels, chewables, lozenges, powders, liquids—is there one that’s best?
Dr. Low Dog: There are advantages and disadvantages of each.
Tablets: They’re cost-effective, shelf-stable, and have longer expiration dates. If you have a healthy digestive tract and aren’t taking medications such as proton pump inhibitors (Nexium, Prilosec) that shut off production of stomach acid, your digestive system shouldn’t have any problem breaking down a supplement tablet made by a reputable manufacturer. One downside: Tablets can be difficult to swallow, but this can be easily remedied by using a pill slicer to cut your tablets in half.
Capsules: They’re easy to swallow and break down quickly. You can also open capsules and put the ingredients into a smoothie, applesauce, or yogurt, making capsules an attractive option for children or those who have difficulty swallowing. Vegetarians/vegans take note: Although most supplement manufacturers use capsules made from vegetable material (veggie caps), some may contain gelatin derived from animals. Check the labels.
Softgels: These smooth, one-piece capsules are designed to hold liquid or oil-based preparations, such as vitamin E or fish oil. They’re easy to swallow and, because they’re airtight, offer a long shelf life. Unlike capsules, they’re currently made almost exclusively from gelatin from animal sources, so they aren’t suitable for vegetarians or vegans.
Chewables: If you like to take your supplements in the form of gummy bears, don’t be embarrassed. You aren’t the only one! Chewables are one of the fastest-growing and most popular categories of dietary supplements. Most contain some form of sweetener and/or flavoring, which could be either natural or artificial—so read labels closely. And vegans and those sensitive to dairy should be aware that some chewable supplements contain lactic acid, which may have been derived from dairy.
Chewables are one of the fastest-growing and most popular categories of dietary supplements.
Lozenges: Designed to dissolve slowly in the mouth, lozenges are usually used to soothe a cough or sore throat. Some supplements are available in lozenge form as an alternative to chewables. Be aware that they may contain some type of sweetener as well as flavorings or colorings. Keep them away from young children who may confuse them with candy.
Powders: Powders are useful when you want to use larger amounts of a supplement. For example, the amount of inositol used for anxiety or sleep is typically 6–12 grams, or 2–4 teaspoons. That would be 12–24 capsules per day! Powders can be added to smoothies and food, and have a decent shelf life. But they are less convenient when traveling or on the go.
Liquids: Some liquid vitamins and minerals are available in a sublingual form, drops that are placed under the tongue for rapid absorption. A classic example is vitamin B. Liquids allow a great deal of flexibility when it comes to dosing, and you don’t have to worry about absorption issues. However, they have a shorter shelf life and are harder to transport, as many need to be refrigerated after opening.
Topicals: Many creams, lotions, ointments, gels, and liquids contain vitamins, minerals, nutraceuticals, and herbal ingredients. Many people open a vitamin E capsule and apply it to prevent scarring when skin has been injured. Epsom salts can deliver magnesium through the skin and relax sore muscles. Calendula ointment is commonly used for minor cuts and wounds.
Q: Are “whole food” vitamins worth it?
Dr. Low Dog: The terms “whole food” or “food-based” refer to vitamins that have undergone a fermenting process using yeast. These products are made by feeding vitamins (some natural, some synthetic) to yeast in a liquid broth solution. As the yeast grows, it incorporates the vitamins and minerals into its cellular structure.
The yeast is then killed and dried, and the vitamins pressed into capsules, liquids, or powders. The theory is that the nutrients incorporated into the yeast are now in a highly bioavailable form. On labels, you may see ingredients listed as “derived from yeast” or “from S. cerevisiae.” Are these food-based or bio-transformed products worth the extra price? Many people think so, as this is one of the faster-growing segments in the supplement industry. In fact, I take a multivitamin-mineral product made using this type of process.
In some cases, though, there is no difference between a synthetic and natural vitamin where the body is concerned. This is the case with vitamin C. If your supplement contains more than 100 mg of vitamin C, chances are high you’re getting at least some synthetic vitamin C. However, natural and synthetic ascorbic acid are chemically identical, and there are no known differences in their biological activities or bioavailability.
Q: Should I take all of my supplements at once?
Dr. Low Dog: Some nutrients can enhance or diminish the absorption of other nutrients. Large amounts of calcium (250 mg or more) can impair the absorption of iron, while vitamin C increases it. Interestingly, in the Southwest, people like to eat beans, which are high in iron, with chili peppers, which are packed with vitamin C. This traditional mixture maximizes the absorption of plant-based iron, which is less absorbable than the iron found in meat. Taking large doses of calcium or magnesium (250 mg or more) can compete with the absorption of other minerals, including each other. I generally recommend taking magnesium at bedtime to help with sleep and relaxation. Take your multivitamin-mineral supplement at least two hours apart from your calcium or magnesium.
Q: When is the best time of day to take supplements? With meals, without? In the morning or at night?
Dr. Low Dog: Most vitamin and mineral supplements are best taken with food to aid their dissolution and absorption. Iron supplements are best taken with food to avoid stomach upset. Multivitamin-mineral supplements and vitamins B-complex, C, and E and can all be taken together at the same meal. I recommend taking them with breakfast.
Take larger amounts of calcium or magnesium several hours apart from other minerals. Calcium carbonate must be taken with food, whereas calcium citrate does not need to be. I recommend the latter. It’s best to take fat-soluble vitamins (A, D, E, and K) and fish oil with a meal containing fat. One study found that taking vitamin D with dinner instead of breakfast increased vitamin D by about 50 percent!
There are a few supplements that should be taken on an empty stomach. Herbal bitters are often taken 20 minutes before a meal to “prime” the digestive tract, revving up the production of stomach acid and alerting the pancreas that food is coming. Enzymes should be taken during or immediately after a meal.
Q: Should people with food allergies be concerned about fillers, binders, and “other ingredients” in supplements?
Dr. Low Dog: Fillers are one area of concern when it comes to allergies. Rice flour is typically used as a filler because it is hypoallergenic, but cornstarch, lactose, or other potential allergens could also be present. If you have a soy allergy, avoid products that list lecithin on the label. Sometimes a label will list vegetable glaze or vegetable coating, which could be derived from corn—a problem for some people and also possibly genetically modified. Read labels carefully.
Q: What about vegetarians? Are there any common ingredients in supplements that may be derived from animals?
Dr. Low Dog: Gelatin is derived from pig or cattle; if the label lists gelatin, the supplement contains an animal product. Look for vegetarian or vegan capsules if this matters to you. Glycerin is often used as a preservative in liquids and as a softener in softgels, and can be derived from animals or plants. If you’re vegetarian, make sure you check the label to ensure it lists vegetable glycerin.
Article adapted with permission from Fortify Your Life: Your Guide to Vitamins, Minerals, and More by Tierona Low Dog, MD.
Tieraona Low Dog, MD, is internationally recognized as an expert on dietary supplements, herbal medicine, women’s health, and integrative medicine. She has served as an advisor on integrative medicine to both the White House and the National Institutes of Health.
Tips for Storing & Organizing Supplements
For the majority of supplements, store in a cool, dry place (such as a kitchen cupboard). And don’t throw out the little packet inside—this keeps out moisture and prevents clumping. Some probiotics need to be refrigerated; check labels.
On the other hand, you shouldn’t store supplements in the bathroom medicine cabinet, as this is the room that sees the most humidity and changes in temperature, which can damage and/or compromise the potency and efficacy of your supplements.
Don’t store fish oil softgels in the refrigerator. This can result in small holes in the softgel coating and cause premature spoilage. The freezer, however, is a good option for fish oil softgels.
Anatomy of a Dietary Supplement Label
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