Perspective: Stone me, not yet another diet craze; The latest diet fad involves looking back to our ancestors. But, as John von Radowitz explains, you have to take a long hard look back to the Stone Age.
Diets seem to come and go like A-list celebrities. Just as Atkins has started to seem passe, a new way of eating is being hailed as the key to slim and stay healthy.
Only it's not really new. For this is the stone-age, or palaeolithic, diet that can be traced back two million years to a time when the earliest humans speared mammoths and dug roots up from the ground.
The food eaten back then had to be either hunted or gathered from the wild. Agriculture, and the birth of human civilisation, did not come until more than a million years later.
Advocates of the palaeolithic diet are passionate in their belief that it is what Nature intended us to consume.
The fundamental claim is that humans evolved as an omnivorous species with genes adapted to natural, raw foods.
Stone-age dieters argue that when about 10,000 years ago we discovered fire and learned how to cook, we started going off the rails food-wise, and have continued ever since.
The palaeolithic diet encourages the consumption of lean red meat, chicken, fish and eggs, as well as fruits, nuts and roots such as carrots, turnips and swedes.
But it forbids a lot of what we take for granted in our diets today - including bread and pasta, potatoes, beans, peas, all dairy products, sugar and salt.
To follow the stone-age diet you have to imagine what it was like to have lived before humans learned to till the land.
It was a hand-to-mouth existence, in which our ancestors survived on wild game, edible leaves, roots, fruits and berries.
They stayed away from many sorts of plant foods, such as beans and seeds, because they tasted bad and made them feel ill. Then, about 10,000 years ago after the end of the last Ice Age, early humans discovered that many things they previously considered unpalatable could be made edible by cooking. The breakthrough opened up a whole new dietary world and changed the course of human evolution.
Heat destroyed the toxins in grains such as wheat, corn, barley and rice, as well as beans and potatoes. Our intake of carbohydrates shot up, perhaps doubling the number of calories obtainable from plants. Such foods were easy to keep and transport, enabling surpluses to be stored away for the winter.
Humans stopped wandering and settled down to farm the land and domesticate animals. Communities sprang up and grew into civilisations that built impressive tombs and temples and waged war.
But, despite all this progress, say the stone-age dieters, our genes remained out of tune with the 'civilised' food provided by agriculture.
In particular, they argue, the food of neolithic, as opposed to palaeolithic, man lacks essential omega-3 fatty acids that are vital to brain development.
Research just published by scientists in Liverpool appears to back up some of their claims.
The scientists found that eating nuts ensured a supply of natural fat, rather than clogging he body with saturated fat.
Fish and nuts both contained abundant omega-3. On the other hand, bread and milk were difficult to digest, the researchers reported in the Journal of Nutritional and Environmental Medicine.
They pointed out that humans are the only mammals to drink the milk of another species. There are many differences between human milk and cow's milk. The purpose of milk is to help infants grow, and for this reason it contains substances called growth factors. Some experts believe the growth factors in milk might promote cancers in adults.
This is said to be especially true of cow's milk, since calves grow at a breathtaking rate as soon as they are born.
According to stone-age dieters, cooking destroys most, but not all, of the toxins in grains, beans and potatoes.
These toxins, also known as 'antinutrients', were developed by plants as a form of protection - to prevent them, or specific parts of them, being eaten. An apple, for instance, is designed as an edible seed distributor. An animal eats the apple, and deposits the seeds in its dung. But the seeds themselves contain bad-tasting toxins that disrupt digestive enzymes and act as pesticides.
Grains are seeds that contain similar enzyme blockers and lectin toxins. Anyone who ate a handful of uncooked flour would become very sick indeed.
Lectins are potentially the most dangerous plant toxins, yet scientists have only recently started to understand them.
They have the ability to stimulate a rangeof cellular 'receptors' - molecules on the surfaces of cells that trigger biological effects when other molecules of the right shape bind onto them.
Lectins are said to damage the cells lining the small intestine, trigger blood clots, mimic the effect of hormones, promote cell division at the wrong time, and disrupt the immune system.
Some experts believe they are linked to auto-immune diseases, and possibly cancer - although this has not yet been demonstrated scientifically.
Enzyme blockers, abundant in all seeds including grains and beans, inhibit the body's ability to digest protein. They are effective poisons - rats cannot gain weight if they have substantial amounts of enzyme blockers in their diet.
They also act as a preservative, allowing seeds to survive a long time before sprouting.
Potatoes contain another family of toxins called glycoalkaloids that are not destroyed by cooking, or even deep frying. They are particularly high in green potatoes, small amounts of which can cause illness.
Exorphins are other food chemicals cited by advocates of the stone-age diet. They are found in dairy products and wheat, and mimic natural morphine-like substances in the body called endorphins. Exorphins act on hormone receptors, and may either stimulate or block them. It's said they could, therefore, affect chronic pain, and addictive behaviour.
In the stone age, meat, offal and seafood accounted for 45 per cent to 65 per cent of the daily diet. The palaeolithic diet was high in protein, fibre, vitamins and minerals, but low in salt and saturated fats.
Some tribes living in Australia, Africa and South America still pursue a huntergatherer existence that has not changed for many thousands of years.
Research has shown that they are remarkably free of many of the ills that plague the rest of us, including arthritis, diabetes, high blood pressure, stroke, depression and cancer.
On the other hand, critics of the palaeolithic diet argue that stone-age people did not live long enough for diseases such as arthritis and cancer to become a serious problem.
Raquel Welch -with John Richardson in One Million Years BC -would not have looked at all like that at all if she'd had to eat what our ancient ancestors survived on. But it may be the best health option for modern man
|Printer friendly Cite/link Email Feedback|
|Publication:||The Birmingham Post (England)|
|Date:||Dec 13, 2003|
|Previous Article:||Perspective: The Iron Angle: Have you heard the one about the noticeboard and the bin?; Local government under scrutiny with a slant.|
|Next Article:||Perspective: What is Bullring actually herding us into?; As shoppers descend on Birmingham in their tens of thousands, Eliot Whittington reminds us...|