Proteins and dieting
A lot of people are dieting these days due to increased obesity levels, observed especially in the developed nations. There have been a number of diets that are flooding the markets, claiming to promote weight loss. One such diet is the low carbohydrate - high protein diet. People on such a high protein diet have been observed to lose more fat than muscle, resulting in weight loss. But there are other studies which do not recommend a high protein diet on a long term basis. So, what is the role of protein (if any) in reducing body weight and is it advisable?
Benefits of a high protein diet
High protein diets do help to lose weight. Most high protein foods are naturally low in carbohydrates and saturated fats. Such diets contain high quality proteins including amino acids that build muscle. As a result, high protein foods help maintain muscle and even help build muscle while dieting and exercising.
Exercising along with a high protein diet has been observed to further help in lowering body weight. The effect of exercise along with high protein, in boosting weight loss has been attributed to the presence of amino acid leucine. Leucine is an essential amino acid which has to be obtained from the diet. It is found in foods such as meat, eggs, soybeans and dairy products. Leucine has not only been found to preserve muscle, but also boost weight loss in collaboration with exercise. That is, when dieters on a high protein diet are engaged in mild exercise, it increases weight loss compared to other dieters on an equal calorie diet but low in leucine. The proposed mechanism of leucine has been reduction in weight by burning body fat.
Another reason for people to be able to lose weight effectively on a high protein diet is that proteins give a feeling of fullness. As a result, dieters feel more satiated and less hungry for a longer time after a high protein meal. Proteins have been shown to reduce appetite both in the short term and long term.
The appetite suppressing action of proteins has been shown by some researchers to be attributed to the gut hormone known as PYY. It has been suggested that PYY sends signals to the brain leading to a feeling of fullness. Further, it has also been shown that high protein diets lead to higher levels of PYY.
High protein foods used in diets
- Casein (milk protein in cow’s milk)
- Whey (natural protein in cow’s milk)
- Low fat dairy products
- Lean meat
Health concerns of a high protein diet
Although high protein diets have been shown to help in dieting, possible side effects, especially on the kidneys and calcium need to be studied in greater detail.
American Heart Association does not recommend high protein diets for weight loss. It can result in side effects such as fatigue, constipation (due to lack of fiber), low blood pressure and low calcium levels. On a long term basis, high protein diets do not provide enough vitamins and minerals which are necessary to meet the nutritional needs of the body. People who cannot effectively use excess protein may be at a greater risk of kidney diseases and osteoporosis (due to calcium depletion).
Thus, a high protein diet can help to lose weight, but it can also lead to loss of important nutrients to maintain good health.
Best way to lose weight
Regular physical activity in combination with a healthy diet containing fresh fruits and vegetables is the best recipe for losing and maintaining weight. There should be enough variety in foods so as to include all important nutrients in the diet. Also, healthier choices like lean meat and non fat dairy products will go a long way in maintaining good nutritional status.