(2) Feed a cold, starve a fever

It's never a good idea to starve yourself when you're ill, unless you're vomiting. It is a good idea to eat to keep your strength up, ideally with plenty of vitamin C-rich foods - especially fresh citrus fruits - as research suggests this could reduce the duration of a cold or flu bug. And whether you have a fever or cold, it's vital to keep drinking to avoid dehydration.

(3) Cracking your knuckles causes arthritis

This myth was probably started by people desperate to stop others who have this annoying habit. It releases gas build-up between the joints, which has nothing to do with joint damage.

(4) Tipping your head back relieves nose bleeds

This is quite a dangerous myth and can cause you to swallow blood and potentially choke. You should squeeze your nose and hold your head forward, preferably over a sink, so the blood runs away.

(5) An apple between meals keeps teeth clean

Although it's better than nibbling sweets, some dentists believe the acids in fruit can be harmful to tooth enamel long-term. Your best bet is to nibble a piece of cheese, which lowers the acidity levels in your mouth and is packed with teeth-strengthening calcium.

(6) Swallowed chewing gum stays in your stomach for seven years

One invented by parents - probably to stop their kids swallowing and potentially choking on gum. As with anything we consume, it will be pushed through the gut and eliminated in the same way and at the same rate as any other food.

(7) Sitting on a hot radiator gives you piles

It won't - piles are normally triggered by straining as a result of constipation or childbirth, not heat. However, it could lower your sperm count. I remember a wooden bench above a radiator at university that we called "the hot seat" and people would sit on it to keep warm. Male medics who knew it wasn't good for their fertility gave it a wide berth.

(8) Carrots help you see in the dark

This myth originated as war propaganda. To explain the increase in downed German planes, the Government claimed eating carrots helped plane spotters to see in the dark. This was to hide the fact it was really due to using new, top-secret radar equipment. Eating fresh fruit and veg can help reduce your risk of age-related macular degeneration, which damages eyesight.

(9) Spicy food gives you stomach ulcers

Doctors believed this for many years and put ulcer sufferers on bland diets. But we now know that peptic ulcers are caused by an infection with the Helicobacter pylori bacteria. However spicy food can sometimes trigger heartburn, an entirely different condition.

(10) You must drink at least eight glasses of water a day

While it's good to stay well hydrated, everyone has different fluid needs, depending on their size and body. Secondly, you can get your fluid intake in lots of different ways without sticking to boring old water. Tea, milk, juice, even soups and fruit and veg will all hydrate you.

... sometimes there's a grain of truth

Never swim after eating

Although a recent survey said this was a myth, I beg to differ. I always tell my grandchildren to wait for at least an hour before they get into the pool after lunch.

My rationale is that, after eating, your blood gets shunted to your stomach to digest the food and away from your exercising muscles. That can lead to a build up of lactic acid, so swimming a few laps too soon after food could cause a sudden cramp.

A pint of Guinness a day is good for you

This does contain small amounts of iron, although drinking it daily isn't a good idea as all booze is packed with calories.

An apple a day keeps the doctor away

There is some truth in this, although many of the benefits are provided by any fresh fruit. Some studies have found that apples, in particular, are good sources of potent antioxidants which may fight cancer.

Fish is brain food

We have now discovered that a chemical called DHA found in fish oil is important in the development and functioning of the brain. One study found that, in people over 65, a high fish intake was associated with a slower rate of mental decline.

Source: Daily Mirror