It sounds so logical: Vitamins are good for you – so if you inject, say, vitamin C or D or B12 or, best of all, a great big honking combo of all the antioxidants, your health will naturally become even better. But do you really need vitamin B12 shots?

Some doctors and nutrition specialists, offer vitamin B12 shots as part of their wellness program. “If a person is run-down or jet-lagged, there is this immediacy to a vitamin infusion,” says one doctor. “You feel more energetic right away.” Well…depends. Which vitamins are you injecting?

If it is a vitamin B12, you may be doing yourself some good – but only if you have a B12 deficiency, which is not likely unless you are a strict vegetarian, vegan, or are well into middle age, says Roberta Anding, a registered dietitian and spokeswoman for the American Dietetic Association.

“It is true that people over 50 lose the ability to absorb vitamin B12,” she says. “As we age, we lose the ability to make something called intrinsic factor, which is a key enzyme that unlocks vitamin B12 from food.” So taking vitamin B12, normally found in meat, may give an energy boost.

Vitamin B12 shots for weight loss Vitamin B12 shots need to be given intermuscularly, which hurts a bit. If it is injected into fat, it is poorly absorbed. Vitamin B12 shots have also been promoted as an aid to weight loss, but there is no evidence that they have this effect, according to registered dietitian Katherine Zeratsky of the Mayo Clinic.

The bottom line Healthy adults do not need vitamin B12 shots or any other kinds of vitamin injections, Anding says; we get plenty from food.

“In fact, we live in this consumer culture of overabundance, and I am far more likely to see vitamin toxicity – too much of a particular supplement – than vitamin depletion,” she adds. “We tend to forget that in high doses, vitamins can act as drugs. We need to respect them.” [via]