Wednesday, February 4, 2015

High protein diet and smoking-Any relation?

Protein is a nutrient that comes from the daily diet needed by the human beings for tissue building and the amino acids contained in the long chain molecule provide the building lock for the body. As there is a limitation with respect to absorption of many molecules across the intestine, complex foods will have to be broken down to simpler chemical entities by enzymes present in the gastrointestinal tract. Specifically proteins in the diet are hydrolysed by a series of enzymes like pepsin, trypsin etc present in excretions of stomach and intestines into amino acids which are then absorbed into the blood for further utilization by the cells. The process of building proteins from this pool of 16 odd amino acids is through anabolic metabolism and there are hundreds of such proteins which are involved in metabolism to generate energy and other vital materials needed for a healthy life.

There was a time in the last millenium when too much focus was laid on protein malnutrition and national and international agencies were working over time to provide protein rich foods to malnourished poor people across the globe. Agencies like World Health Organizations (WHO) and United Nations  International Children's Emergency Fund (UNICEF) are in the fore front fighting against malnutrition among people with special emphasis on women and children. However during the last five decades the emphasis has shifted from protein malnutrition to protein calorie malnutrition as many believe when adequate calories are provided through traditional cereals and pulses the protein needs are automatically taken care of. But there are some countries which are over dependent on only carbohydrate rich foods like Yams and Manioc and the populations there are vulnerable to protein deficiency. Research efforts in the past as well as at present are going on to enrich such foods with proteins from different cheap sources.

According to nutrition experts daily need for proteins among adults is around 50-60 gm and this has to come from a balanced diet containing plant and/or animal food sources. Though plant proteins are not considered as efficient as that from animal sources like meat, fish, egg and milk because of the limiting amino acids concept, people depending on plant foods compensate such handicaps through consumption of mixed diets containing different plant protein sources and cereals. From time to time there have been reports about the ill effects of consuming animal proteins linking it to diseases like obesity, CVD etc, it is more a misconception because it is not the protein per se that can be blamed but the presence of saturated fats in such foods that cause the problem. The differentiation between red meat and white meat and preference of white meat from sources like fish by nutritionists has to be understood in the context of the quality of fat present in them. 

While insufficient protein consumption can lead to diseases like Kwashiorkar and if calorie deficiency is more prominent it causes Marasmas, both the diseases can be fatal if allowed to progress without appropriate intervention. These diseases are characterized by fatigue, pale skin and hair, muscle wasting, diarrhea, infection, edema, swollen abdomen, stunted growth and a host of other symptoms. If WHO is to be believed, one in twelve people in this planet is malnourished and almost 58% of the 62 million mortality recorded is considered to be due to malnutrition! Unbelievable indeed! It is more or less agreed that if adequate income is generated among the economically poor population, mostly in Africa, South America and Asia, they can come out of this trap on their own by buying their needs of food. The million dollar question is how can that happen unless equitable economic development takes place uniformly across the world. 

On the other side of the coin is protein over nutrition. One has to draw an analogy to fat consumption and every body agrees that over consumption will lead to obesity in the long run. With proteins such a consensus is not there still though there are reports implicating over consumption to fatal diseases like cancer,.If that protein comes from animals, chances of developing diseases like cancer are considered some what high, it seems. In a recent report emanating from the US the consequences of over eating proteins were dramatically illustrated when the lead researchers proclaimed that high protein diets, especially during middle age, can increase the chances of cancer as much as that of a smoker puffing out 20 cigarettes a day. This conclusion was arrived at after tracking the lives of thousands pf subjects over a period of 20 years. How far this is correct cannot be judged now unless more data come from other independent scientific groups.

Though comparing high protein eaters to cigarette smokers may be far fetched, it does convey a powerful message about the potential risks involved in those indulging in too much meat eating, especially during their middle age phase of life. An interesting historical observation supports these findings. Eskimos who eat a predominantly meat based diet have a short life span though they have powerful bodies and extraordinary stamina. Same is true with many special groups of population scattered across the world who adopt a predominantly meat based diets excluding carbohydrates in their day to day lives. The relationship between calorie intake and longevity is another phenomenon not understood well and the present studies highlighting protein intake and cancer may also be an area which will attract more scientific groups to unravel the mysteries in the coming years. 

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