Hail protein! So finally scientists have been able to zero in on the nutrient, which will end people's woes. The basis of the well known "rage" diets like Atkins diet and South beach diet lies in the stoppage or restriction of carbohydrate foods. As a consequence protein in the diet is increased manifold. Low carbohydrate is the gen-next mantra for weight loss and rightly so. These diets work in a paradoxical way, not due to carbohydrate restriction but protein inclusion.
In the new study, published in the American Journal of Clinical Nutrition, David Weigle from the University of Washington School of Medicine and colleagues decided to test the hypothesis that increasing protein while maintaining carbohydrate intake decreases the appetite, leads to the consumption of fewer calories and results in weight loss.
In an accompanying editorial, Dr Arne Astrup of the Royal Veterinary and Agricultural University in Copenhagen said, "preventing weight gain is a more complex matter than simply telling people to eat less and exercise more."
A key take-home message of the Dietary Guidelines for Americans concerns calorie control and exercise, with consumers encouraged to choose foods in order to get the most nutrition out of calories consumed.
In the study by Weigle, 19 subjects were assigned three different diets, one after the other. The first two weeks were for a weight-maintaining diet where protein accounted for 15 percent of calories, fat 35 percent and carbohydrate 50 percent.
An isocaloric diet followed for the second two weeks, 30 percent protein, 35 percent fat and 50 percent carbohydrate.
Thereafter twelve weeks were devoted to a diet where there was no restriction on calories but the proportions, again, were 30 percent protein, 20 percent fat and 50 percent carbohydrate.
Measurements of the following parameters were made throughout viz appetite, caloric intake, body weight, and fat mass. At the end of each phase blood samples were taken to measure insulin, leptin (the hormone responsible for hunger) and ghrelin (the satiety hormone).
Results were as follows:-
1. Satiety was 'markedly increased' with the isocaloric diet but leptin was unchanged.
2. With the ad libitum high protein diet, average spontaneous calorie intake decreased by between 376 and 504 per day, body weight decreased by between 4.4 and 5.4 kg and fat mass decreased by 3.3 to 4.1 kg. Leptin levels 'significantly decreased' during this phase and ghrelin increased.
3. As carbohydrate remained at 50 percent during all three phases, the effects of the ad libitum diet would appear to be due to the high protein intake.
These results point to the conclusion that the simplistic approach to weight loss would be administration of high protein diets to obese subjects. True? Well the answer depends on the adverse effects of such a recommendation. Should the obese increase the protein intake from 10 to 20 percent of calories to 20 to 30 percent?
According to research Institute of Medicine, it has found no clear evidence that high protein intake increases the risk of renal stones, osteoporosis, cancer or cardiovascular disease, and sets the acceptable range of protein intake as between 10 and 35 percent of calories.
On the flip side obesity increases the risk of developing cardiovascular disease, type-2 diabetes, arthritis, asthma and back problems. But technically speaking many protein rich sources also contributes the much-dreaded saturated fats in the diet. And saturated fats are known to raise LDL 'bad' cholesterol levels.
"It is preferable to replace sugars from soft drinks with protein from low fat milk, high-fat milk and dairy products with the lean versions, and possibly white bread and pasta with lean meat, without reducing the intakes of fruit, vegetables and whole-grain products," said Astrup.
"Perhaps now is the time to consider the economic and environmental consequences of increasing the population's intake of protein," concluded Astrup.
This is a whirlpool of ideas, refutations and cross-examinations. The problem of obesity is certainly a grave one and the time has come when no one can turn their backs towards it. But whether protein could be the key to bringing the obesity epidemic to its knees, opinion is divided.
So much said and done is not the end! In order to make a conclusive statement lot of aspects both scientific and economical need to be looked on. Policy makers will have a tough time and will not sleep over the matter. The matter will rest only when a declarative statement regarding the safety of the high protein diet is established. If done then it will be a revolution of sorts.
Source: American Journal of Clinical Nutrition
More information on Medindia
Obesity: Obesity may be defined as a condition in which there is an excessive amount of body fat. This is one of the most commonest diseases found all over the world.
Atkins Diet:With obesity being the wide spread issue today, we have indeed given way to various combination of foods to be consumed so as to reach the ideal body weight. Atkins diet is one such example.
South Beach Diet:
What is the south beach diet?
Hey! hang on! What follows is not a mystery novella written on the south beach but a write up on a new concept to weight loss, which proclaims to be a way of life. Created by Dr. Arthur Agatston, a cardiologist, to work with the body safely and effectively. It started as a fad diet like many others including the Atkins diet, now is a rage and people swear by it. It is a three phase diet, the first two being time bound while the third is for a lifetime. It is basically a corrective form of eating where you replace all bad carbohydrates and fats by good ones.