Besides using up kilojoules, exercise helps your brain stick to a diet. University of Pittsburgh researchers studied 169 overweight adults for two years and found that the participants who didn’t follow a three-hour-a-week training plan ate more than their allotted 6 270kJ per day.

The reverse was also true- sneaking snacks sabotaged dieter’s workouts. “One healthy behaviour without the other will not work – you need to diet and exercise to maintain long-term weight loss,” says study author Dr John Jakicic.

Both actions serve as reminders to stay on track. Exercise helps control satiety levels, so you won’t feel hungry afterwards.

Don’t Order Sleepy Meals

Bad news for dieters with sleep deficit: one night of tossing and turning can make you crave fast food, report researchers at New York’s Baruch College. When they reviewed the study participants’ food and sleep journals, those who had trouble falling or staying asleep were significantly more likely to eat fast food the next day.

According to the researchers, people just don’t feel like cooking when they’re tired and irritable. You, however, should suck it up: men who have two fast-food meals weekly gain an extra five kilograms over 15 years, compared with men who dine at home.

Stop off at the supermarket after work rather than the burger joint.

Are Carbs the Key?

Before scaling back on bread, make sure it’ll pay off in fewer kilos. A blood test can identify if a lower-carb diet is best for you. Called a glucose-tolerance test, it measures your body’s ability to move sugar from your blood into your muscles.

When researchers at Children’s Hospital Boston studied 73 obese young adults for almost two years, they found that those with the worst glucose tolerance lost five times more weight when they cut carbohydrates than when they ate less fat.

A likely explanation: if that sugar can’t be moved into your muscles, it’s shuttled to your liver, where it’s converted to fat. Ask your doctor for the test, which also helps determine your diabetes risk.