There's lots of advice out there on how to boost your metabolism and burn more calories, but if you're still not losing weight it could be because you're making one of these mistakes...
1. Not eating enough calories
Cutting back on calories is the best way to lose weight, but don't go too low. Following a very-low calorie diet can be counterproductive as it's likely to damage your metabolism, which will make it harder for your body to burn calories.
One study found that people who ate 1,100 calories per day slowed their metabolic rate more than twice as much as those who ate 1,500 calories per day over four consecutive days.
In another study, overweight participants ate 890 calories per day. After 12 weeks, the total number of calories they burned per day was found to have dropped by 633 calories, on average.
Worse, this drop in metabolism may continue even after you start eating normally again – which means you'll burn fewer calories than before you started the diet.
2. Snacking on the wrong things
When hunger strikes, avoid eating crisps and low-calorie rice cakes (which are high on the GI scale and release their energy quickly), and snack on a handful of walnuts instead.
According to a review in The American Journal of Clinical Nutrition, walnuts contain polyunsaturated fatty acids that enhance the activity of certain genes that control fat burning. Aim to eat a small handful of walnuts each day, making sure to stay within your overall calorie limit.
3. Not getting enough protein
As well as helping you to feel full, research shows that increasing your intake of protein can significantly increase the amount of calories you burn. Some studies suggest that eating protein can temporarily boost your metabolism by about 20–30%, versus 5–10% for carbs and 3% or less for fat.
Good sources of protein include eggs, tuna, and lentils – or up your intake with protein shakes. Not only are protein shakes an easy way to up your protein intake, they've also been shown to be effective at reducing belly fat as part of a weight loss diet.
4. Sitting down too much
Spending too much time sitting is the worst thing you can do for your metabolism. While exercising and playing sports will burn calories and increase your metabolism afterwards, simply standing up or doing the housework can make a surprising difference.
One study found that standing to watch TV burns 16% more calories than sitting down to watch your favourite soaps. Slowly pedal an exercise bike while catching up on your favourite programme, and you'll burn even more calories.
If you need to sit for long periods of time, try to get up and walk about the house at least once an hour to prevent your metabolism from dropping.
5. Your bedroom is too warm
It sounds too good to be true, but sleeping in a cooled bedroom could help you burn fat. That's according to researchers from the National Institute of Health, who found that sleeping in a bedroom cooled to 17℃ (66°F) for a month was enough to double the amount of brown adipose tissue in participants. Why should you care? Well, brown fat burns rather than stores calories and becomes more active in cooler temperatures in order to keep the body warm.
While there's no advice on how much time you should spend in the cold to increase your body's fat burning ability, turning down the thermostat and sleeping in cooler temperatures could make a difference.
6. Not getting enough sleep
If you decide to take the covers off your bed, just make sure you still get a good night's sleep. Not getting enough shut-eye can reduce your metabolism and may cause you to gain weight.
One study found that people who got four hours sleep for five consecutive nights experienced a 2.6% drop in their resting metabolic rate. Shift workers are even worse off. A separate study found that sleeping during the day instead of at night plays even more havoc with the metabolism, reducing it by an average of 8% over a five-week period.
If you've been suffering from lack of sleep lately, the good news is that your metabolic rate should return to normal after 12 hours of uninterrupted shut-eye.
7. Rushing through your resistance workout
Working out with weights is a great way to increase your metabolism, as the more muscle mass you have, the more calories your body burns at rest.
You don't need to become a body builder to benefit. Doing even a minimal amount of strength training is enough to improve your metabolic rate.
One study found that participants who lifted weights for just 11 minutes per day for three days a week experienced a 7.4% increase in resting metabolic rate and burned 125 extra calories per day, on average.
To get the maximum benefit, make sure to do those bicep curls and bench presses slowly. Research shows that the eccentric — or lowering — aspects of these movements are more muscularly damaging, so they require more effort from your body to repair and recover compared to lifting motions. The result? You'll burn more calories.