What's the Buzz Around Vitamin B12?

By Hurley, Judith

What's the Buzz Around Vitamin B12?

What athlete doesn't want to throw the ball harder, run faster, or pump more iron than the competition? The desire to be the best drives many to do whatever they can to get a performance edge, and some high-profile athletes claim they have taken injections of vitamin B12 in an apparent effort to boost energy or performance. But do B12 shots really help?

There's no question that vitamin B12 is useful stuff. It's needed for proper nerve function, synthesis of DNA, and the formation of red blood cells, which deliver oxygen to the muscles, the Office of Dietary Supplements says. The vitamin is thought to affect levels of serotonin, a neurotransmitter involved in muscle relaxation. But things get blurry when it comes to B12 and sports performance. One study of pistol-shooting suggested that vitamin B12 may increase fine motor control. Apart from that, research has not shown that taking either supplements or injections of vitamin B12 will boost energy or sports performance in people who don't have a B12 deficiency.

Who needs it?

Although taking extra B12 doesn't provide any benefits, a deficiency of the vitamin has serious consequences, including anemia, neurological problems, depression, and dementia. Most people get plenty of B12 in their diet, but some groups need to be especially careful:

  • Vegetarians. Vitamin B12 is found mostly in animal foods. Vegetarians who consume milk, milk products, and eggs are unlikely to have a B12 problem, but vegans—who consume no animal foods—could be at risk for a deficiency. Eating foods fortified with vitamin B12 (such as some breakfast cereals) or taking a multivitamin supplement will provide all the B12 they need.

  • Older adults. According to one study, up to 15 percent of adults older than age 65 may be deficient in vitamin B12. That's because with age, the stomach produces less of a substance called intrinsic factor, which aids vitamin B12 absorption.

  • People who take antacids. Vitamin B12 needs an acid environment to be absorbed. Antacids and other medications that neutralize or block the production of stomach acid interfere with vitamin B12 absorption.

For people who need extra vitamin B12, injections offer no benefits over taking the vitamin orally. Swallowing a supplement will do the trick, even for older adults who absorb less B12.

The bottom line: It's important to get enough vitamin B12 from food or a multivitamin. But to win a marathon or pitch a no-hitter, you will probably need to do it the old-fashioned way, through hard work.

Medical Reviewer: [Hertz, Charles MD, Mukamal, Kenneth MD] Last Annual Review Date: 2009-01-06T00:00:00-07:00 Copyright: Copyright Health Ink & Vitality Communications

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