Food myths: the good, the bad and the ugly

"Coffee causes cancer," or "coffee is bad for your nerves" are a few of the things people used to say about coffee: it is bad for you. But today researchers say coffee is better than its reputation - it may even lower your risk of cancer.

Alcohol is bad for your health. But red wine also contains magic molecules like resveratrol, and anthocyanins. So drink it or leave it? Long-term epidemiological studies suggest for women, one drink per day is beneficial (two for men). Then again, a long-term statistical review from the US showed teetotallers die earlier than moderate-to-heavy drinkers. So maybe it's good for you after all?

Years ago, we were told to avoid butter and eat only margarine. The imitation butter spread contains less saturated fatty acids than standard, milk-derived butter. But now people warn margarine is an unnatural product full of chemistry, merged into a product by the food industry.

When people used to die of heart disease or stroke, it was often blamed on cholesterol. As cholesterol blocks blood vessels, doctors said it had to be avoided at all costs. Especially dangerous foods were eggs, cheese and meat. But the body needs some cholesterol and even produces it itself. Now, the fatty biomolecule is seen as less of a villain. But just don't overdo it.

Many people avoid eating frozen vegetables. They believe frozen vegetables hold fewer vitamins than fresh vegetables. But the frozen vegetables contain more nutrients because they are frozen directly after harvest, and do not lie around for days on shelves before being offered to customers.

A few years ago, it was said omega-3 fatty acids could prevent any illness: cancer, cardiovascular disease - even attention deficit hyperactivity disorder and depression. Health experts advised us to swallow omega-3-supplements daily. But now we know more: Yes, these fatty acids are important for some functions in our body. But for most conditions, supplements are not beneficial at all.

Vitamins are essential for your metabolism, so what could be healthier than swallowing vitamin pills every day? Vitamin C especially was said to protect against all kinds of diseases, including common colds. But studies have been unable to prove this. In fact, vitamin supplements may even harm you. At least, that's what they say today ...

Nature is pretty clever. When we need water, we get thirsty. But somebody once said we should drink before we're thirsty - at least three liters per day, or more. The theory may have a basis in the fact that elderly people often lose their feeling of thirst. But normally your body should do a fine job of letting you know when you need to drink.

Milk contains calcium - it's good for your bones and strengthens your immune system. That's what we've learnt. But a decades-long Swedish study suggests people who drink a lot of milk may die early. Is the sugar galactose responsible? Nobody knows. For now, keep drinking milk, but in moderation.

Another baddie on the horizon is wheat. Numerous websites warn of its dangers. They say "it inflames our bodies, causes our guts to leak, and triggers autoimmune diseases." Some doctors - and authors - say wheat may even cause baldness, hallucinations and suicidal thoughts. Despite the fact that there are no studies to support this, many have given up this grain that sustained their ancestors.

If normal food contains too much chemistry - as some say - hooray, organic food is what we need. It is produced without chemical fertilizers or any "evil" substances, we're told. But studies suggest organic food is not richer in nutrients or better for you than non-organic foods. It's just more expensive.

In spite of everything, lifestyle does matter. Statistics show clearly that smoking, drinking excessively and being overweight are unhealthy - they may even kill you. But you shouldn't worry too much about reports hyping one food over another - it comes down to balance. So no matter what, just don't overdo it.