If you're serious about losing weight and making the most of your metabolism, then you might want to think about getting to bed a little earlier. According to research, if you don't get enough sleep this can affect your metabolism and also play havoc with your food choices and exercise patterns. How can this be, you ask??

Lack of sleep has been shown to cause changes in hormone levels in several studies. Cortisol, which is often called the 'stress hormone', plays a big part in regulating metabolism of sugar, protein, fat, minerals and water. Physical or emotional stress raises cortisol levels, and lack of sleep can also do this. Not only does lack of sleep mess with your cortisol levels, but it can also cause insulin resistance. Since insulin not only controls blood sugar, but also promotes fat storage, extra insulin makes maintaining a healthy weight even tougher.

Even if you ignore the studies, it doesn't take a genius to realise that when we don't get enough sleep, it can make us grumpy, teary and generally emotional. What do many people do when they are feeling overly emotional? They reach for a mars bar. Think about it...when you've had a bad night's sleep, your energy takes a nosedive during the day; and it's very tempting to turn to the chocolate vending machine for a quick sugar fix. The foods we crave the most when we feel low on energy are often sweets or refined carbohydrates with low nutrient density and you guessed it....high fat and sugar content!

My client 'Carolyn' discovered this the hard way. For years she struggled with extra kilos that it seemed even a 50 tonne forklift could not shift. It was very frustrating for her to be doing all the right things regarding eating and exercise, yes still being unable to lose weight. But the real problem was that 'Carolyn' was stressed to the max. As well as having 3 kids to look after, 'Carolyn's' high-flying career required her to do a gruelling 90 hour week as well as be on-call weekends.

With an average of four hours sleep a night, 'Carolyn' was seriously deprived. A little prioritising and a lot of work based around Carolyn's belief that she 'must' be there for everybody else at the expense of her own health was required. Once she began to give to herself and get more sleep, the weight dropped easily. And 'Carolyn' dropped off to sleep even more easily!

Similarly, 'Sophie' was a sleep-deprived workaholic whose only way to reward herself was by giving herself little culinary treats. With no relationship to speak of and a marriage first and foremost to her work, 'Sophie' was on a fast track to a heart attack. She was so exhausted at the end of each evening, that take-away food was always the order of the day. The television became her special friend in the evenings, during which time she would snack on auto-pilot.

'Sophie's' challenge was to step back and see the big picture. She had thought that working hard now and sacrificing her physical health would bring her happiness later on. But in the meantime, she was not enjoying the 'Now' at all. 'Sophie' believed that working in a highly paid job that did not inspire her would eventually provide her with the life she desired one day in the future. Meanwhile, her current lifestyle was seriously jeopardising her future in more ways than one.

But we're not just talking about eating more when sleep deprived. For many physically exhausted people, calorie burning decreases, making maintaining a healthy weight even harder. If your extra waking hours are spent in at a desk or computer or in front of the TV, you're not burning many more calories than when you are asleep.

To add to that, when we're sleep deprived, we're often too tired to exercise. Even if we do drag ourselves to the gym, we might workout less intensely than usual. So how much sleep do we actually need? Sleep experts recommend at least eight hours of sleep a night for most of us. Turning off the TV an hour earlier means an hour less munching time. It could also shift your metabolism to make weight loss easier. So make the choice....is it really THAT crucial to stay awake for the latest episode of 'Gossip Girl'? If you do, you might just find yourself the subject of other people's gossip about your massive weight gain. Less TV, more sleep. That's the order of the day.