UNLESS you have one of those metabolisms that burns anything and everything you eat - so you never gain a gram - you're probably always looking for the magic pill.
You know, the ingredient that will allow you to eat whatever you want and still fit into your jeans or your little black dress.
Sadly we have to report that scientists are still working on a magic fat bullet (although those who have invested in the research will eventually be multi-millionaires, so maybe get in now).
Meanwhile, accrediting practising dietitian John Jones, who owns the award-winning business Energize Health and is a sought- after speaker, has come up with a compromise to eating everything you want in his new book The Thermogenic Diet.
As well as giving some very practical and usable lifestyle advice about how to lose weight, how to shop, how to read food labels and how to fit exercise into your life, John explains how you can use the thermogenic effect of food - the heat created in the process of digesting it - to lose or maintain weight.
According to John, certain foods take more energy to digest than others and by making changes to the types of food we eat, we can help our bodies burn fat more effectively.
Here are some of his tips to increase your metabolism by 22 to 27%.
Eat six small meals a day, to raise your metabolism by one to two per cent.
Each time you eat, the digestive system must use energy to break down the food, says John.
"Another advantage of eating regular meals is that it can help control hunger. When you skip meals, your thoughts will be focused on unhealthy foods like chocolates, lollies, hamburgers and chips."
Eat more lean-protein foods to raise it by up to four per cent.
Protein-based food requires more energy to be broken down by the body, according to John.
However, he cautions that this doesn't mean we should stop eating carbohydrates.
"If we increase the protein content of our diet too much, without including any carbs, our body will start to break down muscle that helps to feed our brain and heart with glucose," he says.
"Long-term studies also show a greater risk of osteoporosis for a person on a high-protein, low-carb diet."
Add some chilli to the foods you cook to increase your metabolism by one to three per cent.
Think spicy if you're doing a stir fry.
Drink four cups of green tea a day to raise your metabolism by eight to 10 per cent.
John says it contains ingredients called catechins that stimulate fat breakdown.
Include some wholegrain carbohydrates in your diet to improve thermogenesis by up to four per cent.
These increase the speed at which foods moves through the digestive tract and reduce the amount of time for fat to be absorbed, says John.
"Another advantage is that fibre can help you feel full."
The Thermogenic Diet: Learn how food can do the hard work of weight loss by John Jones is available from August 21 from exislepublishing.com.
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