When research comes out about the value of a particular vitamin or mineral, many people run out and buy bottles of the latest “miracle nutrient” hoping that pills will cure ills. Is it a good idea? Is it safe? How about just a basic multivitamin? Why are such simple questions so hard to answer?
A standard response is, “Why not have a vitamin, it’s like an insurance policy, right?” Wrong – what’s good for 65-year-old Bob the marathoner isn’t necessarily right for 30-year-old Sally who is pregnant. In fact, recent research has shown that having too much – often referred to as “megadoses” – of particular vitamins can hurt you. On the other hand, some multivitamins may not provide enough of a particular nutrient that you’re deficient in.
In a perfect world, you’re getting all of your vitamin and mineral needs from the food you eat – a variety of fruits, vegetables, whole grains, lean proteins and healthy fats. If you’re interested in learning whether your diet is balanced, you can consult with a Registered Dietitian or run a basic nutrient calculation report on a three or seven day food record at a comprehensive nutrition site like the USDA Supertracker: https://www.supertracker.usda.gov/ (note, inputting proper portion size is important for accurate results).
However, the world isn’t always perfect, so here are a few questions you can ask to determine whether you may need a vitamin or mineral supplement:
Am I restricting my diet?
You may be restricting your diet for a number of reasons – weight loss, food sensitivities, allergies or personal preference. Weight loss involves eating fewer calories than your body needs to maintain its current weight, so it’s natural to assume you may not be getting enough nutrients from the food you’re eating. This may be a case where a basic multivitamin is useful. If you’re lactose intolerant, then you may need alternate sources of calcium and vitamin D. If you’re vegan, getting adequate iron, vitamin B12 and calcium from non-animal sources is important.
Do I have a new condition?
Nutrient needs can change when you change conditions – whether they be medical, or even exercise-related. A common “condition” is pregnancy – which requires adequate intake of certain vitamins like folic acid and places extra demand on the body for other nutrients like iron (hence, the need for pre-natal vitamins). On the other hand, highly competitive athletes may actually need a little more vitamin C to support periods of intense training.
Am I deficient?
Vitamin and mineral deficiencies can be the result of increased demands on the body, inadequate consumption or just medical abnormalities. While a number of deficiencies present symptoms, others can be more subtle, which is why a yearly physical and blood work is valuable. Vitamin D is a common deficiency because not too many foods are rich in vitamin D, and sunlight (the other common source) is not as strong at higher latitudes in northeast North America. Anemia is another common “deficiency disease,” which can be a result of low levels of iron, folic acid, or vitamin B12. This would be a time when a larger dose of a particular vitamin or mineral could be prescribed by a physician.
If you’re interested in learning more about how much is too much, check out the USDA upper limit intake for vitamins and minerals here: https://www.consumerlab.com/rdas/
*Note: Before starting any new vitamin or mineral regimen, you need to consult with a qualified healthcare professional as they may interact with certain conditions or medications. For example, some people have hemochromatosis, which is a genetic tendency to store iron. Supplementing iron without medical guidance in this population could lead to life threatening complications.
Jason Machowsky is a registered dietitian, certified strength and conditioning specialist, and certified personal trainer at the Tisch Performance Center at Hospital for Special Surgery.