Question:

I’ve heard that the G.I diet helps to reduce body fat, but surely a low calorie diet causes frequent fat burning due to a calorie deficit?
 

Answer:
Yes, calories do count to some degree. Calories are related more to weight loss, the fewer calories we ingest the more weight we lose, but not all the weight lost will come from fat loss. Generally the quicker the weight loss the more chance it will come from muscle and water loss rather than fat and cutting calories quickly results in rapid weight loss. This is why you shouldn’t just go for weight loss alone and the reason why experts recommend only losing an average of 1 -2 pounds per week. This little and often approach requires a gradual drop in calories so there’s more chance any weight loss will largely come from reduced body fat stores resulting in a better chance of long term success.
 

The G. I. diet works in a similar way but additionally helps to control blood sugar levels which limit the storage of fat through control of insulin spikes. This is where the G.I. diet excels. It tends to target the loss of fat stores rather than just body weight alone. It helps limit the amount of lean muscle loss, thus maintains a speedy metabolism which keeps you burning more energy.

The G.I diet may also result in weight loss as a side effect because many low G. I or natural foods tend to contain fewer calories, thus there is frequently a natural decrease in calorie intake.

The fact is we burn fat all day; the problem is we often cause any fat loss to be replaced at the next meal because many convenient foods contain lots of refined sugars which cause the pancreas to release more insulin. The high insulin levels drive excess fat and sugars into cells for storage. The result is we rarely gain the benefit of a net loss of body fat. If we could stop or reduce the body from storing fat after eating we would naturally see a reduction in stored body fat. The G.I. diet does this well if it is followed correctly. A calorie deficit can also do this but there’s no guarantee because it is dependent on what the individual eats and how much he/she reduces calories. With a low calorie diet there’s always the need to burn off extra energy through exercise because we need to tip the balance in favour of burning more than is replaced to produce a net loss of stored fat. The trouble is the body also breaks down muscle to maintain the amino acid pool (protein available in blood). This causes the metabolism to eventually slow down resulting in the weight loss plateau.