Slim body, fat wallet

So what do weight loss and saving money have in common? A lot.

Most notably, it’s super-tough to tackle these simple things, because changing how you’ve behaved for years isn’t easy. The good news: strengthening one area (say, your finances) can give you confidence to improve another (your waistline). So make a habit of resisting temptation – whether it’s shoes or that second helping.

List cons but mostly pros

Dr James Prochaska, co-author of Changing for Good, recommends focusing on how the pros of eating and spending less outweigh the cons. “People who can’t see a good balance of pros over cons are likely to give up,” Dr Prochaska says. So make a list, noting at least twice as many pros as cons, and you’ll see why good habits are worth it.

Hang with the right people...

Self-control is contagious, found a series of studies by Dr Michelle vanDellen, a social psychologist at Duke University in the US. In one experiment, 36 subjects watched someone make a choice between carrot sticks and biscuits. Later, the study subjects were given tests to measure self-control. Those who’d witnessed the person eating the carrots scored better on the tests. “You can improve your own self-control by being strategic with your social networks,” she says. Dine with friends who order decadent desserts and you’ll find it harder to stop after the main; shop with big spenders and you may end up doing the same.

...in the right places

An obvious suggestion: if you pass a patisserie every day – and you’re tempted to fork out for a chocolate croissant – change your route. A less-obvious tip: it can also help just to imagine places that inspire self-control, says Dr vanDellen. “Research shows that students who think about the library have better self-control over all aspects of life. So do people who think about the gym,” she says. Feeling tempted? Consider hangouts you associate with self-control.

Pay yourself frequently

One of the big stumbling blocks when you’re trying to shed debt or kilos is delayed gratification. Neuroscientists who use MRIs have seen why you have trouble with this: when something you could buy now comes into view, the pleasure centres in your brain go berserk. But when we’re asked to think about buying in the future, the fireworks don’t happen. So reward yourself frequently.

Dr Kevin Volpp, the director of the Center for Health Incentives at the Uni of Pennsylvania, US, designed programs that tripled the rate of smoking cessation in a company by offering $750 rewards along the way for quitters. So if you’re trying to drop weight, try this: give yourself about $40 to spend on something fun (and inedible) every week you stay on target. If that doesn’t fit your budget, an inexpensive treat like, say, a magazine is something you can look forward to.