Almost half the female population of the UK is trying to lose weight, but a new study shows that obsessive calorie-counting leads to obesity. Lucy Atkins reports on how slimming can distort both your mind and your body
The Guardian, Tuesday 14 December 1999
My friend Genevieve is troubled. She is, she tells me, four stone overweight. Yet, for the past four years she seems to have been almost constantly dieting. If she'd lost what her diets promised, she'd be Kate Moss by now. So what's gone wrong? The dieting started, she says, with a slimming magazine. "I'd always been overweight, and conscious that it's a social disadvantage, but not desperate about it." By counting "fat units" like some deranged Bridget Jones character, she lost a few pounds. But chomping raw carrots while everyone else tucks into chips is no one's idea of fun. So she gave up. She regained the weight, plus some more. Then came Weight Watchers. She lost a stone. But anxiety about her "points", hours spent weighing food, not to mention being teetotal while her mates swigged Chardonnay proved too much. "Weight loss began to obsess me," she says. So she stopped, became "a human Hoover" and regained the weight. Next, she bought a book called Stop The Insanity. The sensible title masked an almost entirely fat-free existence that caused her panic at dinner parties, an inability to eat in restaurants and a spiralling anxiety about food. She gave it up. She regained the weight, and more.
Over the next year she tried, variously, to Eat Orgasmically And Still Lose Weight (she didn't); to Dine Out To Lose Weight (she dined, she gained); to simply reduce her food (she increased it again); and to combine food in odd ways. She even joined Overeaters Anonymous. Each time, though, she rebounded. The reality is that my friend Genevieve is far from unusual. Right now around 40% of British women are trying to diet. It's a fair guess that most of them have a pretty unhealthy relationship with food and aren't going to stop dieting when they've squeezed into their Christmas party dresses. And the unpleasant truth is that obsessive dieting of this kind may well damage both their health and their happiness.
Countless studies show that repeated dieting makes you more likely to get heart disease, gallstones, diabetes, anaemia, cancer, and osteoporosis. It can give you lank hair, sallow skin and dull eyes; make you depressed and - crucially - perilously fat. Yesterday, a study published by the American Psychological Association showed that drastic weight-loss efforts (dieting, exercise, appetite suppressants, laxatives, and vomiting) in teenage girls make them more likely to become obese later in life. Those who don't try to lose weight tend to find it easier keeping off the weight. And recently the American-based National Institutes of Health found that almost 98% of all dieters not only regain the lost weight, but put on more. Basically, the message is clear: diets don't work. Still, dieting is big business: slimming clubs, aware of the high recidivism of dieters, offer discounts and arrange advertising campaigns to coincide with seasonal dieting; bookshops are crammed with rapid weight-loss paperbacks; best-selling diet authors are worth millions and the internet hums with quick-fix slimming products.
Perhaps the only reliable thing about dieting is what it does to your mind. Dieters become obsessed with eating. This may be purely psychological - you deprive yourself of something so you want it more. It may also be physiological. In 1995, Oxford University researchers discovered that dieting could actually disturb your brain chemistry. The result is a loss of control over eating that could underlie both yo-yo dieting and clinical eating disorders like bulimia nervosa. The team found that dieting lowered the blood concentration of an amino acid - tryptophan - the main ingredient for making the brain messenger serotonin. Mice that lack the brain receptors for serotonin become abnormally fat: they cannot control eating behaviour. It may be that dieting damages the transmission of the normal messages to the brain (for instance "I am hungry") because the brain lacks serotonin. The brain's serotonin receptors then become hyperactive in an effort to overcome the deficiency: the result is an intense feeling of hunger and the urge to overeat.
Genevieve would certainly agree. She describes her rebounds as "dramatic compulsive eating". The dieting disrupted not only her relationship with her own body, but her entire attitude to eating - food equalled guilt. "The diets themselves were like a mental illness," she says, "they left me physically and mentally exhausted."
Some scientists believe that weight is linked to a protein called leptin, which is actually produced by your fat stores. The idea is that when you reach a certain weight, the volume of leptin in the blood reaches a certain level and tells the body to stop putting on weight. Mice deficient in leptin grow very fat, but can be slimmed down by injecting the hormone.
Only last month, Stephen O'Rahilly, professor of metabolic medicine at Cambridge University, found that an overweight patient, when injected with leptin, dramatically shed pounds. O'Rahilly believes that leptin will lead to the first truly safe weight-control drug: "I'm confident that within a decade we will have effective and safe weight-loss drugs," he says.
The relationship of leptin to weight is, though, highly complex, and more studies will have to be done before we can really understand the relationship between hormones, eating and obesity - let alone start contemplating the possibilities of some kind of miracle cure for fatness. The point is that when we mess with the delicate and hugely complicated system of hormones, proteins and other chemicals which control our appetite and how much we lay down, we may be messing it up for good. That's what's frightening.
And if the fact that you could be warping both your mind and your hormones isn't enough to put you off dieting, there's also the fact that your crash diets may eventually kill you. "We need a high level of the antioxidant vitamins, A, C and E to protect against heart disease and cancer," says Dr James Inglis, of the Health Education Board for Scotland. "Dieters may not be getting enough of these and could be more likely to develop the diseases later in life." What's more, the fat you regain with each rebound may be worse for you than the original fat stores. "When you diet repeatedly," says Professor Tom Saunders of King's College London, "your fat patterning changes. The regained fat is laid down first inside the abdominal cavity, next to your internal organs, rather than between the muscle and skin on your hips and thighs." This is dangerous, he says, because, "fat filters from here into the liver and bloodstream, causing cholesterol levels to soar". This raises the risk of a stroke and can produce gallstones, as some of the flood of cholesterol may crystallise in the gallbladder. In fact, it is now widely accepted that "apple-shaped" bodies are less healthy than "pear-shaped" ones. Also, the more you diet the more painful the process is.
"When you diet, your body compensates for what it perceives as a 'lean period' by reducing its demand for calories," Dr Inglis says. "The only way to overcome this is by increasing your activity." But lack of activity is probably why we're fat to begin with. Imagine life without washing machine, car, Hoover, microwave or TV (and its remote control): let's face it, you'd move around a lot more. Unfortunately, lying back and staying fat isn't the answer. Obesity in Britain has doubled in the past 20 years, making us the fat capital of Europe. And obesity kills. It causes diabetes, cardiovascular disease, sleep problems and infertility. For most of us, though, the best way to lose weight and keep it off is to adopt an active, healthy-eating lifestyle (don't eat too much fat, eat more fruit, veg and carbohydrates and limit your snacks). "There's no such thing as bad food," says Inglis, "Only bad eating habits."
For those of us who can't see the point of running when we're not being chased, the advice is pretty cheery. "You don't have to go to the gym," says Professor Ken Fox, head of exercise and health sciences at the University of Bristol. "If an overweight woman of 12.5 stone simply goes for a brisk 30 minute walk five times a week (even in two 15 minute bursts) she'll lose around 10 lb a year." And, he claims, virtually anything that makes you puff slightly counts. "Raking leaves, Hoovering, even climbing the stairs, are all good forms of moderate exercise," he says. This goes for your children, too. Since 1990 our offspring have become 7% fatter. Those with TVs in their rooms, a stack of computer games and parents who are afraid (or too busy) to let them out, are the first to get fat. Overweight children, often (though not always) become overweight adults. Professor Fox recommends that young people have at least an hour of activity every day - walking to school, say, or just running round the garden bashing things.
Genevieve has just been put on a waiting list for an operation to have her gall bladder removed. But, because she's overweight, the general anaesthetic could be dangerous. This time, though, her doctor has referred her to a psychologist, rather than handing her a diet sheet. She can't reverse the gallstones. But with help she should be able to work out why her dieting has failed her, and begin to lose the weight in a healthy, gradual, sustainable way.
Myths about dieting
• People are overweight because they have slow metabolisms... in fact, recent studies show that fat people have faster metabolisms and burn off more energy than slimmer people simply to keep their bodies going.
• Obesity is genetic... unfortunately, only 1% of the obese can blame their parents.
• Calories from fat make you fatter than calories from carbohydrates... a calorie is a calorie, whether it comes from fat, carbohydrate or protein.
• You can 'spot reduce' body fat... a pear shape will simply be a smaller pear shape after dieting. Exercise, though, may slightly streamline certain areas.
• Reduced-fat foods are always lower calorie... the calorie count can be the same as high-fat foods because of added sugar: check the packet.
• All dietary fat is bad... your body needs a certain amount of it, though excess causes weight gain.
• Carbohydrate makes you fat... nutritionists say most of us need to increase our intake, because it has less than half the calories of fat.
• High-protein diets are good for weight loss... actually they're dangerous (they can permanently harm your liver and kidneys and deprive you of essential minerals and vitamins) and because they are so incompatible with a normal lifestyle, most people give up and quickly regain the weight they lost.
• Eating late at night makes you fat... the human nutrition research centre in Cambridge showed recently that people who ate their main meal at 8pm burned exactly the same calories as those who ate it at lunchtime.
• Food allergy causes obesity... the characteristic of food allergies is actually an increased metabolic rate and weight loss.
• Pregnancy makes you fat... fat stores are built up in pregnancy for breastfeeding, but not excessively, unless the mother stuffs herself silly. There's no metabolic explanation for keeping the weight on afterwards.
• Your metabolism changes as you get older... latest research shows little evidence of a 'permanent resetting of the metabolism' with ageing, though you may be more sedentary and the weight you've gained gradually over the years of eating too much and exercising too little may catch up on you.
• Dieting is a healthy activity... 98% of dieters regain the weight they lost plus more.
History of dieting
1864: Publication of the first diet book, Letter on Corpulence, by William Banting, an English casketmaker, who became alarmed when he could no longer tie his shoelaces.
1873: First mention of anorexia.
1890s: First theory of food components - proteins, carbohydrates and fats - and calorie content.
Early 1900s: Calorie-counting born.
1917: Diet and Health, With Key to the Calories, by Lulu Hunt Peters: 1,200-calorie-a-day diet sells 2m copies.
1930s: Dinitrophenol, an insecticide and herbicide, taken by thousands to control weight; 12 women blinded; others die. Makes a comeback in 1980.
1957: Injection of medication derived from urine of pregnant women, rabbits or mares given for weight loss. It proves useless. Still available.
1960: Overeaters Anonymous founded by LA housewife.
1961: Calories Don't Count, by American Herman Taller, sells 2m copies. (In 1967 Taller is convicted of mail fraud for selling 'worthless' safflower capsules.)
1963: Weight Watchers founded by housewife Jean Nidetch.
1970: Eight per cent of all prescriptions in the US are for amphetamines, which suppress appetite.
1978: Launch of The Scarsdale Diet (700 calories a day; high-protein).
1981: Cambridge Diet, a 320-calorie-a-day liquid diet, is introduced.
1983: Karen Carpenter dies of anorexia.
1988: Oprah Winfrey drags a wagon piled with 67 pounds of fat onto her show to demonstrate what she lost with Optifast.
1993: Cardiologist Dean Ornish publishes Eat More, Weigh Less. Meditation and group support. 'Stop the Insanity', by Susan Powter (low fat and very cross). Oprah Winfrey hires a personal trainer to help her lose weight she regained.
1994: Leptin discovered. Makes fat mice thin. Genetic research continues.
1995: Resurgence of low-carb, high-protein diets begins.
1996: Redux approved by FDA.
1997: Fenphen is taken off the market after studies link it to heart disease.
1999: Low-carb, high-protein diets hog bestseller list. Include Sugar Busters!, Protein Power and The Zone.
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