Vitamins and Minerals: Too Much of a Good Thing?

Can taking extra vitamins be too much of a good thing? Yes. In fact, overloading on vitamins and minerals is easy to do and can be dangerous. 

Vitamins and minerals are essential for keeping your body strong, fit and healthy. Most of us run the risk of not getting enough if we don't eat the right foods. That's why vitamins supplements were created: to make it easy to get your daily dose. Nowadays, however, everything seems to be vitamin-, mineral-, and nutrient- packed, and more supplements are hitting the market than ever before. If you're not keeping track of how much you're consuming, you could be taking too much of certain vitamins and minerals and putting your health in danger. 

How can you overload on vitamins? Think about all the foods that advertise they'll boost your nutrition because they're fortified with extra vitamins. They're everywhere.  For example, if you start your day with a glass of vitamin-fortified orange juice, a bowl of vitamin-enriched cereal, and top it off with a daily multivitamin, you may already be taking more than your recommended daily allowance. If, later in the day, you chug more vitamin-packed juice and munch a power bar, you could be crossing a line. If your lunch includes vitamin-enriched bread and vitamin-infused water, you're may already be overloading—and the day's only half over.

What happens if you take too much? Normally, your body gets rid of excess vitamins and minerals by excreting them in urine and stool. Some vitamins are stored and build up in our systems. While its nearly impossible to consume too many vitamins simply by eating normal foods in a healthy diet, they can add up quickly when you pile on the supplements. When your body takes in way more of certain vitamins and minerals than it can process, the effects can be toxic.

Among the dozens of vitamins and minerals currently available in supplemental form, the Institutes of Medicine say extremely high doses of:

  • Vitamin C can cause gastrointestinal disturbances, kidney stones, and excess iron absorption.
  • B6 can cause sensory neuropathy.
  • Vitamin D can cause hypercalcemia. 
  • Vitamin E can cause bleeding disorders.
  • Vitamin A can cause liver toxicity.

Do you need extra vitamins?  That depends on how you eat.

  • Do you regularly consume a wide variety of foods from all major food groups? 
  • Do you eat fresh fruits and colorful veggies every day?
  • How about whole grains, seeds and nuts, low-fat dairy products and lean proteins like fish, meat, beans and soy products?

If you answered "yes" and wash everything down with plenty of plain water, then you're already providing your body with great nutrition. If you're like many people, however, you eat better on some days than others and don't always supply your body with the right nutrients. Taking a daily multivitamin can help, but all those extra supplements are probably unnecessary. Instead, focus on improving your diet and get your vitamins the old fashioned way: through food.



Institutes of Medicine

Dietary Reference Intakes - Vitamins