MEDICAL MATTERS:It's no wonder new year resolution success rates are so poor and obesity rates are climbing, writes DR MUIRIS HOUSTON
WELL, IT’S that time of year again – time for new year’s resolutions. Health is a perennial favourite in the “I must improve myself” category of resolution. Perhaps it’s a reaction to the “eat, drink and be merry” ethos of the Christmas break. But it is genuinely difficult to go from one extreme of behaviour to another. And as the old wives’ tale has it, “A sweet tooth maketh a sour disposition”.
So here we are, already in sugar withdrawal and we’re supposed to muster the energy to tackle a new diet and exercise regime instantly. It’s no wonder resolution success rates are so poor and obesity rates are climbing.
But what if the obesity epidemic was the result of addiction? This is the intriguing suggestion contained in an editorial in the current issue of the Canadian Medical Association Journal. Although the cause of obesity is multifaceted, chronic overconsumption plays a fundamental role, the authors say. The concept of food addiction is similar to that of other addictive behaviours. "Both food and drugs induce tolerance over time . . . in addition, withdrawal symptoms, such as distress and dysphoria, often occur upon discontinuation of the drug or during dieting. There is also a high incidence of relapse with both types of behaviour," they write.
Their argument is supported by MRI studies, which have shown that specific areas of the brain, such as the caudate nucleus, the hippocampus and the insula, are activated both by drugs and by food. In addition, the opioid blocking agent naltrexone has been shown to reduce cravings for sweet food as well as heroin-like drugs.
Then there is the evolutionary argument. In earliest times, foods rich in fats and sugar – which can be rapidly converted into energy – conferred an adaptive advantage. But we are a long way from famine in today’s western world; instead food technology has enabled the modification of foods to artificially enhance their palatability.
Not everyone exposed to illicit drugs becomes an addict; nor do we all become compulsive eaters just because we are exposed to high-fat, high-calorie foods. An individual’s vulnerability, however, may stem from particular personality traits. There is evidence to suggest that eating is used as a form of self-medication when depressed, anxious or bored.
Clearly, the notion of addiction to food does not replace the role of free will and personal choice. But it may give us insights into why a percentage of people with obesity struggle to reduce their weight, despite personal effort and professional support. Importantly, it may help society modify a developing “blame” culture applied to people who are obese.
There is a thin line between the desirable ban on second-hand smoking and, say, a ban on certain people having access to certain calorific foods. The blame culture poses a real risk of us accepting the concept of a “ health police”, which to my mind sails a little too close to fascist thinking.
A recent worry is emerging evidence suggesting that children who regularly consume energy drinks become dependent on them. Caffeine acts on parts of the brain that mediate reward and addiction, potentially affecting future preferences for foods or drinks paired with caffeine.
Energy drinks are different from other soft drinks in having a high caffeine content; they are promoted as a way to relieve fatigue and improve performance. Most energy drinks contain about 80mg of caffeine per 250ml can. The same amount of tea contains around 30mg, and percolated coffee contains 90mg.
There is an acceptance that long-term drug treatments to reduce risks from preventable conditions such as type 2 diabetes, hypertension and coronary heart disease are necessary. Should we also accept that many people now need drugs (and in some cases, surgery) to cut the health risks of obesity?
However, it is unlikely that medication alone will ever “cure” obesity. Indeed, the history of weight-loss pills is not a happy one. Amphetamines caused extreme nervousness, insomnia and addiction. Among other diet drug “mistakes” were thyroid hormone, which caused hyperthyroidism; fenfluramine, linked to heart valve abnormalities; and phenylpropanolamine, associated with heart problems. And it is unlikely there will ever be medication that can help people maintain weight loss unless they continue to limit calories or increase exercise.
Addiction or not, health resolutions are very much part of the equation. Good luck with yours.