How to Evaluate Vitamins and Supplements
Everyone needs a balance of essential nutrients from a variety of foods to stay healthy. Yet it’s not always easy to eat right when you’re on the go. That’s why some of us reach for vitamins and supplements to fill in the gaps. Yet, with a plethora of multivitamins, herbs, and botanicals out there, how can you tell if a supplement is safe -- or right for you?
Questions to Ask About Vitamins and Supplements Although there’s contradictory evidence as to whether a daily multivitamin staves off disease, many people add them to their diet to maintain or boost health. Others, such as premenopausal women, sometimes choose individual vitamins and minerals, like iron, to fill in specific gaps. If you’re evaluating supplements and vitamins to add to your diet, here are questions to ask your doctor, pharmacist, and/or registered dietitian:
What health benefits does this supplement offer me?
Is there any research supporting the use of this supplement?
Do I need this supplement for my health, either to treat a medical condition or help prevent disease?
What is the recommended dose for this supplement?
When and for how long do I need to take this supplement?
Which is most appropriate and effective for me -- a pill, powder, or liquid?
Which form of the vitamin (vitamin D2 or D3, for instance) is the best?
Does this supplement or vitamin have any known side effects?
What are the best brands of this supplement in terms of quality, safety, and researched effectiveness?
Does this supplement interact with any medications or foods?
Will I need to stop taking this supplement or vitamin if I have to undergo surgery?
Which Vitamin Form Should You Choose?
Once you know which vitamin or supplement is right for you, you’ll discover many can be bought as pills, liquids, or powders. One difference between them is the rate at which your body absorbs the supplement and how quickly the supplement becomes active. For example, liquids are absorbed faster than pills. In other cases, the medical action of a particular supplement only occurs when it is in a dry extract form, such as a capsule or pill. Other products do better as a water-based or alcohol-based liquid formulation. Ask your pharmacist or health care provider if you are confused about the correct form of a particular dietary supplement.
Certain supplements are in pill form because they become ineffective, or even dangerous, if exposed to stomach acids. Some people need to take a liquid if they have difficulty absorbing vitamins or supplements from a pill, or even if they have difficulty swallowing capsules or pills. Not all formulations of a particular vitamin are the same. For example, vitamin D supplements come as either vitamin D-2 (ergocalciferol) or vitamin D-3 (cholecalciferol), with some preliminary evidence showing that vitamin D-3 tends to be the more active form. Also, there are several different types of vitamin E, and some experts feel that a mixture of the natural tocopherols and tocotrienols is the best. When in doubt, talk with your doctor about which supplement suits your needs.
The FDA does regulate dietary supplements; however, it treats them like foods rather than medications. Unlike drug manufacturers, the makers of supplements don’t have to prove their products are safe or effective before selling them on the market. Instead, the FDA can force a supplement to be removed from the market only if it proves that the supplement is unsafe. That’s an important point to keep in mind. A supplement could be on the market for years before enough people had adverse health effects to prove it’s unsafe. However, there are some efforts in the works to bring supplement manufacturers up to certain standards (called GMP) that are similar to those for pharmaceutical makers. In addition, manufacturers are required to list contact information on the bottle in case there is an adverse effect. These effects are being collected through the FDA Medwatch system in the hopes of more quickly and efficiently finding suspect products and removing them from the public.
If you eat a balanced diet rich in whole grains, fruits, and vegetables, look for a multivitamin with no more than 100% of the daily value of most vitamins and minerals. Although vitamins are essential to our bodies, in high doses some vitamins can disrupt biochemical pathways. Avoiding high doses is especially important with the fat-soluble vitamins A, D, E, & K because these vitamins build up in your body and can become toxic. (Water-soluble vitamins are excreted in urine if you take more than your body needs.)
People Who Should Avoid Supplements and Vitamins
Supplements are not recommended for people with certain health conditions. Also, some supplements can interact with medications. Always talk with your doctor or health care provider before adding vitamins or supplements to your diet.
1. Pregnant or breastfeeding women, because some kinds of supplements can be dangerous to the baby. A daily prenatal
vitamin supplement is perfectly suited to pregnant and lactating women.
2. Those taking certain medications, including heart, immune-suppressing, and steroid medications, diuretics, blood
thinners, and aspirin. All drugs have the potential to interact with dietary supplements, but interactions with these drugs can
lead to potential problems that are particularly severe.
3. People who are going to have surgery, because some supplements may lead to bleeding and other dangerous
4. Those being treated for or with a history of cancer, because some supplement could encourage the growth of cancer
Smart Vitamin and Supplement Buyers
1. Look for evidence about the supplement’s effectiveness in published scientific studies. Search for such studies in the
National Institutes of Health (NIH) PubMed database: http://www.ncbi.nlm.nih.gov/pubmed.
2. Call the manufacturer and ask what published studies they have to substantiate their claims and what quality-control
systems they have to ensure the ingredients listed on the supplement label are actually in the bottle.
3. If a product claims it will “cure” a disease, is “all-natural,” or has a “money-back guarantee,” be on guard. Any
supplement that sounds too good to be true likely is. Choose brands labeled with the NSF International, US Pharmacopeia, or
Consumer Lab seal. These insignia verify that the supplement actually contains the ingredients stated on the label, and that the
product doesn’t contain any contaminants or potentially harmful ingredients.
4. Be wary of supplements produced outside the United States. Many are not regulated and some may contain toxic
Storing Supplements and Vitamins
Supplements don’t last forever, and to maintain their strength they need a little care. After purchase:
1. Keep vitamins and supplements in a dry, cool, dark place (avoid bathrooms and other damp spots).
2. Make sure all supplements are stored on a high shelf or in a locked cabinet, out of children’s reach.
3. Some vitamins and supplements lose their viability when they sit on the shelf for too long. Do a regular check of your
vitamins and supplements and throw out any that are past their expiration date
Always let your doctor or health care provider know about any vitamins or supplements you plan on taking, especially if you have a chronic condition or are on regular medication. Not all vitamins and supplements are appropriate for everyone, and certain types of supplements can have potentially dangerous interactions with medications you are taking.