I absolutly think not!

At least not how calories are currently calculated. The whole point of high fat, low carb diets like Atkins is that you get most of your energy from fats.

The way calorific intake is calculated, you get 9 calories from every gram of fat, 4 from carbs and 4 from protein.

However, on a diet like Atkins these sums start to go wrong. There are tow ways in which the body burns fat. The first way is when it is burned bu brown fat cells to produce body heat. Everyone does this, and yes, the fats give a full 9 calories.

On a diet like Atkins however we go into ketosis. In this case fats are irreversably changed into ketones which can be burned by the muscles and brain. However, we can't store them well and many are washed away in our urine and excreted in our sweat and even our breath. So, each gram of fat gives a much lower amount of calories to the body - maybe 4 or 5.

The other point is protein. Our bodies don't burn all the protein we eat. They use a lot of it for repairs.

I average 2,000 calories a day according to fitday, but as I get 70% of my calories from fat, 25% from protein and only 5% from carbs, the actual amount I burn willbe much less than 2,000. More like 1,300 and this doesn't even allow for the subtraction of the protein I am not burning!

All the above is the 'metabolic advantage' Atkins talks about in his book.

So a calorie is not a calorie if most of your calories come from fat.