The concept of a healthy balanced diet may be rewritten. Mixed meals of proteins, fats and carbohydrates may be associated with obesity, suggests a new study;a high protein only or high carbohydrate only diet is more beneficial. The researchers also found that the liver enzyme alanine transaminase (ALT) may be used to predict one's body weight. ALT can be a useful weapon in the global war against the obesity epidemic.
Excessive weight, once thought to be a marker of affluence, is now perceived as a harbinger of bad health and premature death. Obesity is now known to carry the burden of diabetes
The view was very simple and won international acceptance; everyone shouted in unison, 'it's all about the lifestyle'. However if this is true, why doesn't caloric restriction and physical exertion help everyone reverse weight gain? Interestingly most of contemporary methods of weight loss prove ultimately unsuccessful. So there are multiple driving factors in the development of obesity, heredity being one of them.
Recent years saw the advent of several alternative hypotheses:
• Infection with a virus called adenovirus-36
• Bacteria residing in the human gut that alter the absorption of nutrients
• Sleep deprivation
None of the theories are universal. Factors vary from individual to individual. Recent evidences suggest that variation in body frame may play an integral role in the development of obesity. One with a lean trunk volume may have a thick layer of adipose tissue.
Body Mass Index (BMI)
The body mass index (BMI)is a determinant of the body weight status. Accordingly, the following classification is used based on the calculated BMI of an individual:
• BMI ranging between 18-24.99 kg/m2- Healthy
• 25.00- 29.99 kg/m2 category - Overweight
• Exceeding 30 kg/m2- Obese
Now comes the question- how to predict one's body weight? Is there a particular test that can predict if an individual has a tendency to develop obesity? Blood cholesterol, blood pressure and random blood glucose levels, have all been used employed as predictors of good health. Well, a recent research concludes that the liver enzyme alanine transaminase (ALT) is more closely associated with bodyweight than the traditional markers.
Alanine transaminase (ALT)
ALT, a part of the liver function test, has been considered as a marker of liver damage
often associated with a condition called non-alcoholic fatty liver disease. ALT is a central figure in the body's protein metabolism. This enzyme is known to convert alanine, an amino acid, to another compound called pyruvate. Pyruvate is then converted to acetyl CoA, an important biochemical molecule for cellular respiration. Alternatively, there is also a provision for acetyl CoA to enter a pathway that is involved in the production of fat. The route taken by the acetyl CoA depends on the energy requirements.
Based on this knowledge, it can very well be deduced that in individuals with a high level of the enzyme ALT, the body metabolism is routed in the direction of gluconeogenesis and fat deposition. So naturally, weight gain will ensue.
The Modern Diet Plan
A mixed meal of protein, carbohydrate and fats may lead to the accumulation of body fat stores and thus obesity. This is because, carbohydrates and fats are burned faster to satisfy the body's energy needs, while the slower digested protein is converted to a compound called malonyl Co A and stored as fat.
The results of the study was based on the findings from 46,684 subjects that included 19-20 years old Swiss male conscripts and published data on 1000 Eskimos, 518 Toronto residents and 97,000 North American Adventists.
May be we are not far from a time when technology permits ways to manipulate the levels of ALT and thereby empowering medical therapy to produce weight loss or prevent weight gain. Future diets may be ones that separate proteins and carbohydrates. Man may have to alternate his dieting between herbivorous and carnivorous meals, making omnivorous diets infrequent. In a sense, this means we will return to the very original dietary habits of our ancestors!
1. Modern diet and metabolic variance - a recipe for disaster?
2. Nutrition Journal 2014