Something small, but very important, could be tipping the balance and preventing you from getting slim. Find out what and you can do something about it!

People who watch between one and two-and-a-half hours of TV per day are 93 per cent more likely to be overweight than those who watch less than an hour per day, found university researchers in Australia. Heart rate, blood pressure and metabolic rate all slow down when you're slumped in front of the TV, meaning you burn 20 to 30 fewer calories per hour compared with just sitting still. As a result, if you watch five hours of TV a day, you can gain more than a pound each month.

It's amazing how many dieters agonise over every last calorie in a meal, and then knock back several alcoholic drinks in one evening. As well as the effect of excess alcohol on your liver and the cancer risk, alcohol calories really do count. One tiny (125ml) glass of red wine contains 85 calories, a Baileys around 170 calories and a pina colada at least 260. Stick to a couple of units a night as part of your calorie allowance.

The hormone cortisol is produced as a response to stress and was originally the trigger to refuel the body after a crisis. Now we're not fleeing wild animals - or trying to catch one for dinner - the appetite-stimulating effects of cortisol can mean we eat too much when we're stressed. To fight the fattening effects of stress, get moving - exercise lowers cortisol and raises levels of stress-busting endorphins. 

Most of us who steadily put on weight over the years do so by having a daily energy surplus of just 50 to 100 calories. That's the equivalent of just one chocolate biscuit per day. If it's surplus to your calorie requirements, that biccie can mean you put on a pound every 40 days - or around nine pounds in a year.

A study of over 6,000 people aged 25 to 60 found that in both sexes and every age group, married people had a higher body mass index (BMI) than those who had never been married. If you want to eat the same foods as your partner, keep your portions 20 per cent smaller than his. Go for potato-topped pies, use spray oil for fry-ups and have oven chips instead of going to the chip shop. 

Charting every little up and down in your weight can be disheartening. Fluctuations of a couple of pounds can simply reflect the time of the month, or whether you've been to the loo. Information from America's Weight Loss Registry suggests weighing yourself regularly is important, but that once a week is best for motivation levels.

Diet drinks may seem like the perfect choice when you're slimming, but they might actually hinder your weight loss. University scientists in the US found that animals fed with artificially sweetened yogurt consumed more calories and gained more weight than animals eating yogurt flavoured with real sugar (glucose). This seems to suggest artificial sweeteners may disrupt the body's natural ability to ‘count' calories based on foods' sweetness. So don't rely on artificially sweetened food and drinks - switch to water.

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