Developed by Barry Sears PhD, the 'Zone Diet' is the latest in a long line of attempts to get a fresh angle on weightloss, and is currently among the 5 most popular diets in the States, partly because dieters report losing up to 5 pounds in the first week, and up to 1.5 pounds each week thereafter. Dr Sears main thrust is that food is 'medecine' for the body, and not just the 'fuel'. He proposes an "ideal" ratio of carbohydrates, proteins and fats - namely 40% carbs to 30% protein and 30% fat, which is supposed to keep the body within a healthy 'zone' determined by hormones. Slightly complicating matters is the concept that some carbs are good, and some are bad. Refined Carbohydrates such as pasta, potatoes and bread are bad, and need to be strictly controlled.

Dr Sears believes the human body's digestive system works best by eating only 2 main food groups, namely Lean protein and natural carbohydrates (from fruits and fiberous vegetables). The good Doctor also advises disciples to eat small but regular meals, at least times 5 per day. Added to this are the other key parts of the diet (there are 4 components in all) - the diet itself, the use of monounsaturated fats, Omega-3 fish oil dietary supplements and of course exercise. This combination is said to burn excess body fat while increasing energy. Adherents report increased vitality not to mention improved mental abilities and fewer health problems.

To follow the Zone Diet, you create 'zone meals' or snacks based on the 40% 30% 30% ratio of carbs, proteins, and fats. In terms of portion size, use your own hand as a guideline (for example, a protein portion will be approximately the size and thickness of your palm). As for carbs, it depends on whether they are good or bad carbs. You can have 2 "big, loose fists" of good carbs, but only 1 "tight fist" if you prefer a bad carbohydrate like pasta, potatoes or bread.

Fats are also essential, and if your protein component is light on fat, you can add some olive oil, or a couple of olives. If you prefer, a small pile of nuts can be used instead. Unlike some diets, the Zone Diet doesn't 'ban' any foods as such, but you are 'strongly advised' to keep bad carbohydrates down to a quarter or less of your total carbohydrate intake. And stay off the caffeine - no coffee, tea, or fizzy colas even the diet variety. There are pre-prepared 'Zone Diet' snacks and ready meals available, although Dr Sears insists these are not necessary as long as you follow the guidelines. You should also exercise, both aerobically and anaerobically, 3 times a week minimum for at least 20 mins with an additional warm up time and stretching.

Once you reach your ideal weight, you can add more fat to your diet in order to provide your body with energy without using your stored fat reserves. Typically you would double your fat allowance to start, then see if your weight holds. Make sure they are monounsaturated fats though!