Obesity is now close to crisis level in the developed world. Over a billion dollars a year are now spent researching the metabolic, genetic and neurological foundations of obesity, but this work has yet to make any impact in solving the problem. There is no magic bullet, and probably never will be, to rid us of the obesity problem. The only way to lose weight is to consume fewer calories than you burn up. If this were easy to do, we would not have an obesity problem. But, it is not too difficult either. Studies show that a behavioural modification approach, recording calorie intake, weight and exercise, selecting modest goals and joining a support group, can effectively tackle obesity. The current situation is summarised by David H. Freeman in the February 2011 edition of Scientific American.
Obesity is linked to sharply increased risk of heart disease, stroke, diabetes, several kinds of cancer (colon, rectal and prostate), osteoarthritis and gout.
Freeman notes that – “If current trends continue it [obesity] will soon surpass smoking in the U.S. as the biggest single factor in early death, reduced quality of life and added health care costs”. Currently one third of Americans are obese and another third are overweight.
The situation is Ireland is not much better – 18% of the population are obese and 39% are overweight. We have the fourth highest incidence of obesity in Europe amongst adult males and 22% of our 7-12 year old children are obese (Barron, Comiskey and Saris, Brit. J. Nursing, 9 July 2009). Ireland has seen a 30% increase in obesity over the last 4 years. Obesity in Ireland accounts for at least 2,500 deaths per year.
Why do we find it hard to lose weight? Well, our basic metabolism and physiology was fine tuned over many years of evolutionary adaptation in an environment where famine was a constant threat and eating loads of energy dense food, when you could get it, made sound sense. And we are adapted to conserving ingested calories during times of scarce food supply. Now we find ourselves in a world awash with cheap tasty food and very efficient food marketing mechanisms for shoving this plentiful food down our necks. Junk food is now cheaper than fresh food. So, many of us take in far more calories than we burn up in activity and this surplus intake is stored as fat.
A host of special diets have been formulated for weight control. These diets do not work for most people in the long run. Friedman cites evidence that two thirds of dieters end up two years after starting such diets weighing more than when they started. Other studies have shown that initiatives such as posting calorie counts on meal options in fast food outlets have little or no effect on influencing teenagers’ choice of food items.
As we all know, the big difficulty in losing weight is sticking with the new habit of reduced food intake. When you start to eat less you quickly and easily lose a kg or two, but further weight loss becomes more difficult to achieve. Your body quickly senses the reduced calorie intake and takes effective action to use the calories you do take in more efficiently. Most people find the slow progress hard to take after the initial heartening results. They start to pay more attention to their inevitable food cravings and frequently give up the struggle.
Friedman cites persuasive evidence that the only weight reduction approach that has any real hope of success is the behaviour modification approach. This basically involves monitoring your weight, calorie intake and your exercise regime, and joining a support group who are following the same plan. It is important not to be over ambitious. Start by making small and sustainable reductions in calorie intake and small increases in amount of exercise (e.g. use the stairs instead of the lift).
Don’t go on diets that drop major food groups – eat balanced diets that incorporate lower fat and sugar intake. Discuss these changes in your support group, get advice and encouragement from the others and offer your views to them. Slowly but surely you can establish new sustainable habit. The longer you stick with this approach the easier it gets. You get positive reinforcement from feeling and looking better due to the weight loss, you feel physically and psychologically better because of the increased exercise and you get positive reinforcement from the others in the weight-loss group.
Behaviour counselling interventions have been shown to be effective in treating a wide variety of problem behaviours and disorders. For example, even brief behavioural counselling interventions have been shown to reduce the number of drinks taken by problem drinkers by up to 35 percent for up to 4 years. One would expect a behavioural programme that can reduce alcohol consumption to be equally effective at reducing food intake.
William Reville is Professor of Biochemistry and Public Awareness of Science Officer at UCC http://understandingscience.ucc.ie
This article first appeared in The Irish Times on 3rd March 2011