By Dr Ananya Mandal, MD
Obesity is a public health problem affecting millions worldwide. Obesity depends on the imbalance between intake of calories and expenditure of the same with regular physical activity.
There have been several studies to devise the perfect diet that can help prevent weight gain, reduce excess weight and maintain a healthy body weight. However, no diet is perfect and a onetime cure for obesity and overweight.
High protein and low carbohydrate diet is one such fad diet that has been claimed by some to help reduce weight and maintain it at healthy levels. Like other fad diets, high protein diet failed to live up to its expectations.
Advent of the high protein diet and its efficacy
The high protein and low carbohydrate diet gained popularity in the 1970’s. This form of diet as favoured in ancient times as well. Greek athletes for examples preferred a high protein diet. They were popular in the late 1960s and early 1970s with the publication of the Atkins’ Diet, The Drinking Man’s Diet, Stillman’s Diet and the Scarsdale Diet etc.
Studies from Duke University, Philadelphia Medical Center and University of Pennsylvania show that average weight loss with high-protein diets during the first six months of use, is approximately 20 pounds. This is not significantly different from other diets and other studies that looked at carbohydrate-restricted diets also show that the amount of carbohydrate consumed had no effect on the degree of weight loss.
Risks associated with high protein diet
Apart from being marginally effective in weight loss, a high protein and low carbohydrate diet can be harmful as well. Some of the side effects of this diet include:-
Risk of ketosis – Ketosis is a condition seen in severe and uncontrolled diabetes mellitus as well as in long term starvation. Normally glucose is the energy source in the body. It is obtained from carbohydrates normally. When there is a shortage of glucose for prolonged periods the fatty acids are broken down to obtain glucose in the body. This causes generation of ketone bodies. An increase in circulating ketones alters the body’s acid-base balance leading to acidosis, low phosphate levels, osteoporosis, and kidney stones. Severe ketosis can be life threatening. Lack of carbohydrates in diet can lead to an increased risk of ketosis.
Risk of heart disease – High protein diets are mainly composed of animal meats and proteins. These are also typically rich in dietary cholesterol and saturated fat. High dietary cholesterol leads to increased risk of heart disease
Risk of kidney damage – Proteins are normally excreted by the kidney. High animal protein diets over time can cause excessive load on the kidneys and damage their functions. Plant protein, on the other hand, has no harmful effect on the kidneys.
Risk of complications of diabetes – Diabetes itself raises the risk of ketosis, heart disease and kidney damage. High protein diets can aggravate these problems.
Risk of bowel cancer - Regular meat consumption, as is necessary in high protein low carbohydrate diets, increases colon cancer risk by about 300 percent according to research from Harvard University.
Risk of osteoporosis - Very high protein intake leads to increased loss of calcium via urine. This leads to calcium loss from bones and leave the bones brittle and prone to fractures. IT also leads to increased risk of osteoporosis.
Risk of liver damage
Risk of nutritional deficiencies - The American Heart Association says that, “High-protein diets are not recommended because they restrict healthful foods that provide essential nutrients and do not provide the variety of foods needed to adequately meet nutritional needs. Individuals who follow these diets are therefore at risk for compromised vitamin and mineral intake, as well as potential cardiac, renal, bone, and liver abnormalities overall.”
Reviewed by April Cashin-Garbutt, BA Hons (Cantab)
Last Updated: Apr 10, 2013