Vitamins, minerals, herbs, and supplements Archive

Calcium is billed as the bone-building nutrient. But some experts argue that we should pay more attention to exercise and vitamin D.

Starting on your 51st birthday, current government guidelines say you're supposed to consume 1,200 milligrams (mg) of calcium daily. With advancing years, both men and women begin to experience a decline in the density of bones that makes them weaker and more likely to break. In essence, your bone becomes more porous, and calcium supposedly fills in the holes.

But the amount of calcium adults need continues to be debated. The critics say there's little evidence that high intake has more than a marginal effect on bone density and fracture prevention. They say exercise and reversing vitamin D deficiency are not promoted enough and are more important for bone health. Professor Walter Willett, chair of the nutrition department at the Harvard School of Public Health, is one of the leading lights in the critical camp.

The nutrient appears to have modest prevention power.

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Vitamin C is often touted as a natural cold remedy. The nutrient is featured in supplements promising to boost the immune system. Nobel laureate Dr. Linus Pauling famously claimed that taking large doses of vitamin C helps thwart a cold. Is there something to these claims? "The data show that vitamin C is only marginally beneficial when it comes to the common cold," says Dr. Bruce Bistrian, chief of clinical nutrition at Harvard-affiliated Beth Israel Deaconess Medical Center.

About vitamin C

Our bodies don't make vitamin C, but we need it for immune function, bone structure, iron absorption, and healthy skin. We get vitamin C from our diet, usually in citrus fruits, strawberries, green vegetables, and tomatoes. The Recommended Dietary Allowance for men is 90 milligrams (mg) per day, and for women, it's 75 mg per day.

A few supplements show limited, possible benefits for people with heart disease. But some popular ones don't—and others may be dangerous.

Prehabilitation aims to increase your strength and health before, not after, a medical procedure.

Rehabilitation can help get you up on your feet again after surgery or a physical setback. But some surgeons are increasingly turning to an innovative approach called prehabilitation in hopes of easing that recovery in the first place.

Prehabilitation, commonly called prehab, is an individualized medical program designed to help people — often those who are older or frail — better withstand and bounce back from an anticipated physically stressful event, such as surgery, says Dr. Julie K. Silver, an associate professor and associate chair of the Department of Physical Medicine and Rehabilitation at Harvard Medical School.

What you do before procedures can help get the best results.

If you're planning a complex medical procedure or surgery, you'll hear a lot about the steps you'll need to take afterward to speed up recovery and reduce complications. But it's equally important to focus on your health beforehand, too.

"Preparing both your body and mind before an invasive medical procedure can help you better manage and overcome the many stresses you encounter," says Dr. Julie Silver, associate chair for the department of Physical Medicine and Rehabilitation at Harvard Medical School. "If you are healthier and stronger going in, you have a much higher chance of avoiding setbacks."

On call

Q. Can specific types of supplements help reduce my risk of developing prostate cancer?

A. Most studies of vitamin and mineral supplements have had disappointing results. In fact, some even appear to increase prostate cancer risk. Here's a rundown on where everything stands.

Memory slips are aggravating, frustrating, and sometimes worrisome. When they happen more than they should, they can trigger fears of looming dementia or Alzheimer’s disease. But there are some treatable causes of forgetfulness.

Research we're watching

Taking supplements that contain high levels of biotin (vitamin B₇) can lead to falsely low results on a blood test used to detect heart attacks, according to an FDA warning issued late last year.

For adults, the recommended dietary allowance (RDA) for biotin is 0.03 milligrams (mg), which is easily obtained through a healthy, varied diet. Many multivitamins and prenatal vitamins contain far more biotin than the RDA. And some supplements — particularly those marketed to improve hair, nails, and skin — contain 20 mg, or nearly 650 times the RDA.