Do You Need To Take a Multivitamin?

Grocery stores and pharmacies offer aisles of dietary supplements, including vitamins from A to zinc, all touted to improve your health and well-being. Amid that cornucopia of products are multivitamins, a temptingly simple, one-a-day option to ensure you get a range of vitamins and minerals. Why not give yourself this nutritional safety net?

About one-third of American adults take a multivitamin regularly, and half take either a multivitamin or another vitamin or mineral supplement regularly. But before you put that bottle in your shopping cart, consider these points:

• If you eat a diet rich in lean protein, fruits, vegetables and whole grains, a multivitamin is unnecessary.
• Some nutrients may be poorly absorbed in combinations provided in multivitamins.
• Vitamin supplements may cause side effects, ranging from mild stomach upset to more serious health problems including an increased risk of bleeding after an injury, liver damage, kidney stones and even higher risk of certain cancers.
• Vitamins may interact with medicines you are taking. For example, vitamin K can reduce the ability of the common blood thinner warfarin to prevent blood from clotting.

In other words, a vitamin supplement is not for everyone, although there are specific habits and health conditions that could make it difficult to get certain nutrients, and that’s when a good multivitamin may be warranted.

What Are Vitamins?

Vitamins are essential organic compounds our bodies need in very small quantities for certain functions, including metabolism, cell growth and development. They work as catalysts, triggering various biochemical reactions in our cells to fight infections, improve vision, build strong bones and muscles, and regulate hormones, among other things.

The 13 essential vitamins are vitamins A, C, D, E, K, and the B vitamins — thiamine, riboflavin, niacin, pantothenic acid, biotin, B₆, B₁₂ and folate. Each performs unique functions in the body. For example, vitamin D helps the body absorb calcium, necessary for strong bones and teeth, while vitamin C promotes tissue repair and wound healing, and vitamin B₁₂ is essential for nerve function and making red blood cells.

Vitamins work in two ways, and the difference is important. The C and B vitamins are water soluble, which means they are absorbed with water and excreted in urine if not used.

Vitamins A, D, E and K are called the fat-soluble vitamins because our bodies digest, absorb and store them like fats. Because these vitamins take longer to clear the body, too much could lead to toxicity causing health problems ranging from hair loss to nausea and vomiting to liver damage. If you plan to take a fat-soluble vitamin, it’s important to talk to your healthcare provider to assure proper dosage.

What Problems Can Vitamin Deficiency Cause?

While too much of a fat-soluble vitamin can cause health problems, so can too little of any vitamin. General symptoms of vitamin deficiencies include fatigue, muscle weakness, skin problems and cognitive concerns.

Other symptoms depend on the vitamin you are lacking. For example, brittle hair and nails are a symptom of biotin deficiency, and vision problems could be caused by a lack of vitamin A. Perhaps you’ve heard of scurvy, a horrible disease common among sailors in earlier centuries caused by an acute lack of vitamin C. Once the cause was discovered, the British Navy ended the plague by giving its sailors limes or lemon juice – earning them the nickname "Limeys."

Vitamin deficiencies are diagnosed through routine tests that measure the amount of each in the bloodstream. These tests may be performed as part of your annual medical visit or ordered whenever a vitamin deficiency is suspected.

Who Is at Risk of Vitamin Deficiency?

Even with a healthy diet rich in lean protein, fruits and vegetables, some people develop vitamin deficiencies and need a multivitamin. Pregnancy, for example, creates a temporary need for additional vitamins, while aging adults with difficulty absorbing nutrients may need a boost.

Others at risk of vitamin deficiencies include:

• Vegans, vegetarians and others with dietary restrictions
• People with certain medical conditions like celiac disease, inflammatory bowel disease or cystic fibrosis
• Anyone who has had gastric bypass surgery
• Those taking certain medications, some as common as antacids
• Individuals whose diet consistently lacks in fruit, vegetables and other nutrient-rich foods.

Multivitamin, Individual Vitamin or No Vitamin?

Your regular healthcare provider or a registered dietitian can help you decide if you would benefit from an individual vitamin (a targeted approach for a specific deficiency) or a multivitamin (a safety net approach).

If you choose to take a specific vitamin, be sure you know the toxicity risk, particularly for vitamins A and D. And if you opt for a multivitamin, read the labels carefully to be sure of what you are getting and in what amounts.

And finally, take a multivitamin with realistic expectations: Aside from usually minor side effects, these supplements are not harmful. However, there is no evidence they reliably reduce the risk of chronic disease even when taken for up to a decade or more.

Whatever you decide, you should prioritize a healthy, balanced diet, which is nature’s way of providing our bodies with the nutrients and micronutrients we need.