Why it’s so hard to keep weight off
Why do so many people lose weight, only to put it back on? Larissa Ham wonders whether it is it even in our control.
When Libby OakesAsh reluctantly decided to undergo gastric sleeve surgery four years ago, the early signs were good – her weight rapidly dropped from 135 to 80 kilograms.
‘‘What they don’t tell you is all the side-effects. And what they also don’t tell you is that there’s a honeymoon period for gastric sleeve,’’ says the 58-year-old, who has since put about half the weight back on.
The Canberra woman says she lost some of her hair, has low iron and requires monthly B12 injections.
And she says the psychological problems that led to her overeating in the first place weren’t addressed.
Professor Michael Cowley, of the Monash Biomedicine Discovery Institute, says that most people who lose weight regain it, often even after surgery.
‘‘The current estimates are that about 80 per cent of people who lose weight will regain it – about 20 per cent of people can successfully keep it off,’’ he says.
Cowley believes this is partly due to a ‘‘set point’’, which he says is our bodies’ tendency to stick to a certain minimum weight, which drifts upwards with time.
‘‘It’s not a hard-coded set point but you have an innate tendency towards a weight that’s determined by your genes and your epigenome,’’ he says.
‘‘Then you have environmental pressures, whether that’s how much activity you’ve got in your life and how much food you eat. Those three factors weigh against each other and create a point of balance that you go back to.’’
A major factor is the fact that as we age, we lose muscle – which means we burn less energy, leading to weight gain if activity doesn’t increase, Cowley says.
While we generally can’t change our body’s ‘‘set point’’, we can alter how much we eat and move, he says.
‘‘It’s clear people can successfully change their weight up and down. You can’t change the set point, but we can change the things that push against it.’’
And while you might assume that surgery would lower the body’s ‘‘set point’’, that isn’t the case, says Cowley. However, the surgery will likely decrease your hunger, and the amount of food you eat, leading to successful weight loss, if food intake can be controlled.
He believes that gastric sleeve surgery – in which about twothirds of the stomach is cut out, leaving just a narrow tube – can be a very effective solution for many individuals, but only if a surgeon has a strong patient engagement programme with adequate support.
Professor Amanda Salis, of the University of Sydney, agrees that almost everyone regains weight. But she says there are still tangible health benefits in losing weight, however temporarily.
‘‘There’s relief from the joints. There’s relief from arthritis. Even long term, there’s a reduced risk of cardio metabolic disease if a person has lost weight – even if they’ve regained it all.’’
Oakes-Ash is now trying to lose weight again slowly through a healthy diet, counselling and exercise. She believes psychological support is crucial for anyone battling extreme weight gain – particularly for those who choose surgery.
As with many overweight people, her path shows the reasons for obesity are rarely just as simple as eating too much.
‘‘I was always very fit, very slim, very active but I married a man who had an addiction problem,’’ she says.
‘‘Over the years, I developed what they call co-dependent behaviours, which happens to a lot of people that live with alcoholics or drug addicts, they develop their own addictions to something else to cope. For me, it was food.’’
The tipping point for surgery was when she fell over her grandson and couldn’t get off the floor. ‘‘I was just miserable really, very depressed.’’
Now Oakes-Ash’s main focus is on being able to do the things she enjoys, such as cycling or playing with her grandchildren.
‘‘I don’t do those things to make me thin – I do those things because they give me joy and I can’t do those if I’m 50 kilos overweight,’’ she says.