They are the Philosopher’s Stone of the 21st Century: antioxidants, touted as a universal cure-all. Naturally occurring chemicals, they are found in fruits and juices, made into supplements, and are even added to make-up.
Every week we read about a new superfood with more and more of these apparently beneficial chemicals – and the concept is beguiling.
Antioxidants enhance the immune system’s defence against the diseases caused by free radicals. They include Vitamins A, C and E and selenium, and we have been told they may help prevent cancer, heart disease and even Alzheimer’s.
But adding extra antioxidants to our diet gives no benefit. You can eat as many blueberries or strawberries – or whatever the antioxidant-containing food du jour is – as you like and it won’t stop you getting these illnesses. And it may be bad for your health.
BATTLE OF THE FREE RADICALS
Some antioxidants are produced by the body and some by plants, and so they can be derived from the diet. Their job is to combat free radicals – highly reactive molecules formed as a natural by-product of cellular activity. Free radicals also result from cigarette smoke, strong sunlight, and breathing in pollution.
They present a constant threat to cells and DNA.
We know they can lead to cell damage, cancer, diabetes and cardiovascular problems. Free radicals have also been implicated in everything from strokes to Parkinson’s and Alzheimer’s.
Antioxidants stop the chain reactions triggered by free radicals. So it may seem entirely reasonable that it would be a good thing to eat and drink more antioxidants. But this is by no means the case.
PACKED WITH GOODNESS?
You might have seen some antioxidant-containing products labelled with a number, usually in the thousands. This is the oxygen radical absorbance capacity (Orac) number.
It compares the antioxidant with a standard substance called trolox – itself an antioxidant. Cranberries, for example, have an Orac level of 8 983, which is related to the number of molecules of trolox that would have the same antioxidant strength. The number makes it possible to compare different foods. So theoretically, the higher the Orac number, the better the food.
In reality, beyond a certain point, there is no benefit. In 2008, a study showed no benefits from Vitamin C and E supplements. There is no recommended daily amount of antioxidant consumption.And although there is evidence that antioxidants may have an effect on cancers, much of it is based on experiments on free radicals in cells cultured outside the body, in labs.
We know that people with poor diets are more prone to a host of diseases, and that those who eat a balanced diet with at least five fruits and vegetables a day, take exercise, and other very mundane things, have the best chance of not becoming ill.
But trials where people have consumed excessive levels of antioxidants by taking supplements have found that, if anything, they harm your health.
A Cochrane Review published last month, which looked at the results of hundreds of individual studies, found that current evidence did not support the use of antioxidant supplements in the general population or in patients with various diseases.
And when the review looked at the mortality rate over 78 randomised clinical trials for a range of conditions and using various antioxidants, those consuming antioxidants were 1.03 times more likely to die early.
Another clinical trial last month showed that antioxidant supplements didn’t slow down the progression of Alzheimer’s. Two 1994 clinical studies showed a possible increase in lung cancer when taking antioxidants.
IT’S ALL IN THE DOSE
Almost all things are poisonous in large enough quantities. Similarly, the amounts of antioxidants found in foods are relatively small, so it would be difficult to overdose.
Fruit has plenty of other benefits – vitamins that are crucial for healthy functioning and fibre for good digestion, but, like everything, you can take too much.
Excessive consumption may cause damage to the enamel of the teeth or cause stomach problems.
It is only the excessive consumption of antioxidants through unnecessary diet supplements that could cause any concern.
YOU CAN RUB ON THE BENEFITS
Using antioxidants on the skin, rather than eating them, may have benefits.
Clinical trials have shown that they provide considerable protection against the formation of free radicals in the outer layers of skin when added to sunscreens.
THE TRUTH IS DULL
How can we avoid cancer, heart disease, diabetes and the like? Don’t smoke, don’t drink to excess, eat a sensible, balanced diet and don’t get fat. It’s boring, but true.
We know for a fact that the big killer diseases are caused by unhealthy lifestyles.
It would be lovely if eating blueberries or popcorn could counter ill-health, but it doesn’t. And no matter what you do, you can get ill anyway. That’s life. – The Mail on Sunday