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12 Ways Vitamins Are Doing You More Harm Than Good

Think those extra vitamins can't be doing you any harm? Think again.

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Probably not. Most people can get everything they need from a varied enough diet.


Some people do need to take certain vitamins. For example, the NHS advises pregnant women to take folic acid and people who don't get enough sun exposure to take vitamin D. And vegans take vitamin B12 to supplement their plant-based diet.


2. Vitamin C won’t help your cold.


Vitamin C is vital for healthy skin and helps iron absorption along too. But all those other things you've heard about it stopping you getting a cold? There's not a shred of evidence for them.

Regularly taking vitamin C before you get ill can shorten your cold slightly. Starting once you already have symptoms doesn't do anything, though.

3. The idea that vitamin C can cure a cold was spread by two-time Nobel prize winner Linus Pauling, long after scientists knew it wasn't true.

At the age of 65 Pauling was told by self-styled “biochemist” Irwin Stone (whose training consisted of two years of chemistry in college) that if he took 2000mg of Vitamin C a day, he’d live for another 25 years.

Pauling took the advice, even increasing the amount until he was on to 18,000mg a day a few years later, and in 1970 wrote a book urging others to do the same.

5. In fact, regularly taking vitamin E or beta-carotene could make you more likely to die of cancer or heart disease.


In a study 29,000 Finnish, male smokers were given vitamin E, beta-carotene, both, or neither. Those taking supplements didn’t fare any better than those without – in fact, they were more likely to die from lung cancer or heart disease than those not taking anything.

A 1996 study (PDF) involving 18,000 people with a higher than average risk of lung cancer ended early when researchers realised that those taking vitamin E or beta-carotene were dying from cancer and heart disease 28 and 17% higher than those who didn’t.


10. Multivitamins, vitamin B6, folic acid, iron, magnesium, zinc and copper supplements have all been associated with increased risk of death in older women.

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This study tracked nearly 39,000 women over 18 years. The increase in absolute risk of mortality was biggest for copper supplements at 18%.

The increased risk of mortality was associated with beta-carotene and possibly vitamin E and vitamin A, but was not associated with the use of vitamin C or selenium. The current evidence does not support the use of antioxidant supplements in the general population or in patients with various diseases.

12. In 1972, worried about the lack of evidence for taking high doses of vitamins, the FDA tried to regulate multivitamins.

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They wanted manufacturers to prove pills containing more than 150% of a vitamin's RDA was safe before they could sell it. But the bill failed, so now vitamin manufacturers can put as much as they like in each pill.