What not to eat
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Once, there were vegetarians and carnivores. Today, there’s a bewildering variety of food regimes. But which diet is really best for us? Kate Craven reports
Many of us have aspirations to eat more healthily, hoping that a better diet will improve our health, and boost how we feel and look. We all know that vegetables are good for us, so would eating more of them and junking meat forever be the answer? And which of vegetarianism’s many derivatives should we opt for? Are each as healthy as their disciples believe or are food faddists doing themselves more harm than good? (To say nothing of the inconvenience they cause to dinner party hosts.)
THE CARNIVORE
Are the eating habits of the carnivore that bad? Nutritionist Patrick Holford says there are distinct advantages to eating red meat. It is a good source of iron, zinc and protein. But there is also reason for caution. Meat can be a source of excess saturated fat, and hormone and antibiotic residues. And a 1997 report by the World Cancer Research Fund states that there is an increase in the risk of cancer when substantial amounts of meat are eaten. This evidence was strongest for colorectal cancer. The fat in meat is a possible risk factor, as are other constituents of meat, such as protein and iron. As a result, the organisation advises against eating more than 80g of red meat per day, which is about the size of a pack of cards.
There is some evidence to suggest diets high in grilled and barbecued meat increase the risk of stomach and colon/rectal cancer. This is mainly linked to the consumption of highly charred food. Cancer-causing substances (carcinogens) are formed when fat or meat juices are heated to high temperatures and they can bind to the surface of the food.
There are other dangers, too, says Holford, author of the Optimum Nutrition Bible. Excess protein is a contributor to osteoporosis, kidney problems and constipation.
THE SEMI-VEGETARIAN
So, what if I cut out red meat and become a semi-vegetarian or fishichickitarian? The first obvious benefit is that chicken tends to be lower in fat than red meat. But while a 1970s chicken averaged 9g of fat, today’s chicken has 23g due to poor diet and lack of exercise. You are better off with organic chicken, which contains 19g. But eating fish is even better, says Holford. “More fish means less mental health problems, such as depression,” he says. There aren’t any disadvantages to this way of eating, he says, as long as you choose fit birds.
THE PISCITARIAN
So how about cutting out chicken, too, and if fish are so healthy, become a dedicated fishitarian? There are many benefits associated with eating oily fish, which are high in omega 3. Population studies suggest that omega 3 fatty acids could play a role in memory and concentration. They are thought to protect against heart disease, cancer, type 2 diabetes, arthritis and other joint problems, gut disorders and ME, and help fertility. Fish also have anti-inflammatory properties and are linked to low cardiovascular risk. They are rich in vitamin D, and, therefore, linked to low cancer risk.
But there is urgent need for caution. Fish and shellfish have a natural tendency to concentrate mercury, often in the form of methylmercury, a toxic organic form. Species high in the food chain, such as swordfish, king mackerel, albacore tuna, shark and tilefish contain higher concentrations of mercury. There are concerns about the effects that mercury could have on humans, particularly unborn children. Methylmercury exposure may also increase the risk of cardiovascular disease. The Food Standards Agency advises expectant mothers to avoid shark, swordfish and marlin, and to limit their consumption of tuna, because these are the fish with the highest levels of mercury.
THE VEGETARIAN
If too much mercury puts you off, how about becoming a full-blown vegetarian, just sticking with dairy, milk and eggs, but no flesh? Overall, a meat-eater is likely to visit the doctor, or be admitted to hospital, twice as often as a vegetarian, and is likely to suffer from degenerative diseases 10 years earlier than a vegetarian, states a survey by Professors John Dickerson and Jill Davies from the University of Surrey.
“From the viewpoint of optimum nutrition, a vegetarian diet has many more strengths than weaknesses,” says Holford. “It is very difficult to reach the ideal fibre intake unless one’s diet is predominantly made up of lentils, beans, wholegrains and vegetables. Consequently, vegetarians have faster gut transit times and considerably lower risks of digestive diseases, including cancer. While a third of the UK population has diverticula - pockets in the large intestine that can become inflamed - there is half the incidence in vegetarians.”
Vegetarians who avoid meat and fish have the second lowest risk of cardiovascular disease, after vegans. They also have lower blood cholesterol levels and blood pressure. A vegetarian diet meets the recommendations for fat, protein and carbohydrate intake much better than the typical diet of a meat-eater. “What we are meant to be achieving in our diet is probably no more than 20 per cent of calories as protein, 30 per cent as fat and 50 per cent as carbohydrate,” says Holford. “So, what you want to do is eat food that is close to that. Vegetarian sources of protein, such as nuts, seeds, beans, lentils, soya and quinoa (a grain which boils like rice), contain about 20 per cent of calories as protein and about 50 per cent as carbohydrate.”
Cancer rates are also lower in vegetarians, says Holford. He believes this may be partly because vegetarian diets contain “anticarcinogens”, such as beta-carotene found in carrots, beetroot, tomatoes and other fruits and vegetables. Vegetarian women are less prone to osteoporosis, perhaps for this reason.
But such a diet is not without its disadvantages. “In these days of fat phobia, some people, including vegetarians, go overboard on avoiding fat,” says Holford. “This can be dangerous if sources of essential fatty acids are avoided. These are vital for proper brain development in children. Essential fatty acids are foods in nuts and seeds, and their oils. The best oils are cold-pressed sesame, sunflower or safflower oil, or tahini. These need to be included in the diet of vegetarian children and adults.”
THE VEGAN
Vegetarianism it is then. But wait! Milk consumption is linked to increased breast and prostate cancer risk, says Holford. It is also a common allergen and carries an increased cardiovascular risk. “Many nutritionally unaware vegetarians live off wheat and milk (for example bread and cheese), the two most common food allergens,” he warns. Zinc also tends to be low in vegetarian diets.
The best option then, it seems, is to become a vegan. “Provided they eat lots of beans, lentils, nuts and seeds (essential for adequate protein), this diet is associated with low cancer risk as it is high in fruit and vegetables,” says Holford. Research in Britain has found that vegans, who avoid all animal produce, including eggs and dairy produce, tend to be leaner. But Patrick has more words of warning. The diet will be low in B12, unless it is supplemented. “Low B12 raises homocysteine, which is linked to increased risk of poor cognition in children, depression in women, memory decline and Alzheimer’s disease. It will also be low in omega 3 and phospholipids, found in eggs. It also lacks vitamin D.”
SO WHAT’S THE IDEAL COMBINATION?
There seem to be disadvantages and advantages to them all. So which one would Holford recommend? “I’m a vegan who eats eggs and fish. I don’t eat meat and milk. I’m allergic to dairy. The optimum diet is low in dairy, high in fish - with an emphasis on the carnivorous fish, such as salmon and mackerel - and low in meat. I don’t think you have to avoid meat. The most critical thing about meat is to have fit meat. I’m not anti meat. I’m anti fake meat.”
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