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Skinny people have higher metabolisms
Generally, the opposite is true: the larger you are, the more calories you need to burn each day just to keep your body going. But there may be some exceptions. Mutations in a gene called KRS2, which reduce the ability of cells to metabolise glucose and fatty acids to provide energy, are twice as common in obese people as slender ones. But they are still rare.
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Middle-aged spread is inevitable
Ageing triggers hormonal changes in both men and women, and these can influence your predisposition to weight gain. Declining testosterone levels in men reduces muscle mass, which in turn decreases overall metabolic rate, while . But weight gain isn’t inevitable if you remain active and eat a bit less as you age.
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Thin people digest less food
When Claude Bouchard at the Pennington Biomedical Research Center in Baton Rouge, Louisiana, compared people’s stools, he found little difference in their energy content regardless of how predisposed they were to gain weight. Typically, about 3 per cent of the calories consumed are excreted in the faecal matter, he says. “This doesn’t change following overfeeding.”
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Turn down the thermostat to lose weight
Babies are born with large deposits of brown fat, which actually burns fatty acids to generate heat. Adults were thought to have none, but we now know that slender adults have some. What’s more, .
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Sleep can make you thinner
Sleep deprivation is thought to make you hungrier than usual, as it decreases your levels of leptin, the “fullness hormone”; increases ghrelin, the “hunger hormone”; and impairs normal release of insulin. However, too much sleep also increases the risk of obesity.
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Dieting permanently reduces your metabolic rate
Dieting will depress your metabolic rate. Indeed, the very act of eating increases it, through the release of a hormone called oxyntomodulin, which also blunts appetite. However, there’s little evidence for the idea that you inevitably regain all the weight you have lost because repeated yo-yo dieting permanently blunts your metabolism. In fact, crash dieters and those who lose weight more slowly ultimately regain the same amount.
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You continue to burn calories after exercising
After exercising your metabolism is elevated as your body recovers and repairs itself. This depending on the duration and intensity of exertion. The effect tends to last longer following resistance exercises such as weight-training than endurance exercise but, even then, it is pretty small and tails off with time.
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Exercise on an empty stomach to burn more fat
“If you eat before workouts you will have a little more glucose, which might mean you can work harder,” says Michael Ormsbee at Florida State University. “But if you go in fasted, you will probably burn fat faster – although you might not be able to maintain the same level of intensity.” He recommends combining both strategies.
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Nutritional supplements can boost your metabolism
Many are touted. Most probably don’t work. , says Ormsbee, but it is likely to be tiny, and you would be better off improving your regular diet than taking supplements.
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Eating more frequently boosts your metabolism
While eating temporarily boosts your metabolic rate, it also affects your body’s response to insulin – the hormone that regulates levels of glucose in the blood. , men were fed the same diet, either as three meals or 14 snacks. Those who ate less frequently had higher metabolic rates, were less hungry and had better control of blood glucose.
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Some foods are actively slimming
Contrary to popular belief, the caffeine in coffee and green tea won’t increase the rate at which you burn fat while exercising, but , allowing you to exercise for longer. Capsaicin – the substance that gives chilli peppers their heat – . seems to improve the body’s response to insulin. And a recent study suggests that .
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Eat fat to burn more fat
found little difference in people’s overall metabolic rate, regardless of whether they ate a high fat, low carb diet – like the Atkins diet – or a low fat, high carb one. Protein might make a difference, though. People eating a high protein, reduced carbohydrate diet burned between 60 and 120 extra calories a day, possibly because protein requires more energy to digest than refined carbs. Protein is also thought to boost the feeling of fullness.
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You have to “feel the burn” to get results
Running at 6 kilometres per hour burns exactly the same number of calories as walking at 6 km/h. . A 73 kilogram person who burns 74 calories per kilometre running at 11 km/h and 52 calories per kilometre walking at half that speed will actually burn 30 calories more walking 2 kilometres than running 1 kilometre.
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Eating at night will pile on the pounds
“If you want to eat sugar or carbohydrate it’s probably better to do it in the morning because your sensitivity to insulin is better then,” says Karine Spiegel at the Centre for Neuroscience Research in Lyon, France. “If you eat it during night time you are more likely to store it as fat.” This might help explain the finding that a high calorie breakfast and low calorie dinner than a small breakfast and large dinner.
