Secondly, carbohydrates is said to be the first fuel, that is, the fuel that body prefers to burn for energy. Therefore, by this line of argument, its not difficult to understand why it is said by many that in the absence of carbohydrates in the diet, we would be lacking energy and become energy-less. How true is the aforementioned statement about significance of carbohydrates in diet?
To know the answers for all these questions, read on to know the scientific truth and facts about the two matters spoken of in the previous paragraphs.
1) We do not need carbohydrates because the primary fuel source for the body is not glucose but its fatty acids released from body’s fat cells.
If we have not eaten a meal recently and the insulin level in the body is low the body primarily uses fatty acids as energy source and not glucose from liver glycogen. Stored fats are the source of fuel that the body prefers to burn. Our fat stores are NOT a long term savings account that the body dips into only when body is starved of food as it is believed by many who have the erroneous idea that carbohydrates is the primary fuel for the body (therefore they argue that carbohydrates is important to maintain healthy blood glucose which in turn gives us energy to perform many metabolic functions). The idea that the body takes excess calories and stashes them away as fat till the body is starved, and only then the fat in these tissues is mobilized and used as fuel is WRONG!
Ernst Wertheimer, a German biochemist and the father of the field of fat metabolism has suggested that fat continuously flows out of our fat cells and circulates around the body to be used for fuel and, if it’s not used for fuel then returns to the fat cell (Wertheimer & Shapiro, 1948). Over the course of any 24hrs period, fat from the fat cells provide a significant portion of the fuel to the cells of the body.
The reason many dietitians think (and like to tell us) that carbohydrates are somehow the preferred fuel for the body, which is simply wrong is due to the fact, that the body burns carbohydrates before burning fats, because that’s how the body keeps blood sugar levels in check after a meal, and because too much glucose in the blood is toxic for the cells. In a carbohydrates-rich diet (which most people eat), the cells will always have a lot of carbohydrates to burn before the body get to the fat.
Hence, body fat is the preferred fuel source for the body and not carbohydrates! You still would have ample of energy and full of energy if you live and eat primarily proteins and fats rich foods.
2) Carbohydrates make us fat and not simply calories in general.
Carbohydrates (starchy & sugars especially so) are the one that elevate insulin (protein too stimulates insulin but its effects on insulin is far more measured than carbohydrates). This insulin, in turn, instructs the body to store away all the nutrients [fatty acids, proteins, glucose] and keep it locked up in the cells.
Therefore, the fatty acid broken-down from the body’s fat tissues (and converted into ketone bodies), that were previously being used by the muscle and organ tissues as fuel is now locked up into the fat cells in the presence of insulin. Hence, stopping fat loss and encouraging fat gain! And this is why we gain fat and find it difficult to loose it fast by being on a diet that is rich in carbohydrates.
Carbohydrates are always easily overeaten, hence, we would attribute gaining fat to eating “a lot” of food rather than attribute to the fact that we have been eating something very specific (carbohydrates) that makes us fat or we should understand the fact that carbohydrates in our food is making us eat a lot, which is making us fat due to the action of carbohydrates(glucose) in the blood, which promotes insulin that in turn promote the formation of fats from glucose. Glucose is a nutrient that the cells can instantly utilize for energy, hence after a carbohydrates rich meal the blood glucose goes through a yo-yo pattern of glucose in the blood. Therefore, for the times the body goes low on glucose and slowly switching to fatty acids for energy, in that time lag, we start (or cells) starts craving for energy, and hence, we will start craving for more carbohydrates again.
So now next time when you want to loose fat, you know what you have to do! Cut the carbohydrates calories from your diet, and the tissues of the body will be nicely fueled by the fats stored in your body, when you are on a protein and fats calorie rich diet.
Get On, Get Going,
-Vijay Thakkar
Reference:
Wertheimer, E. and R. Shapiro (1948). “The physiology of Adipose Tissue.” Physiological Reviews, Oct (28): p. 451-64
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