CARNITINE-THE NEW VILLAIN IN HEART ATTACK

"Heart attack" is a much feared "two words" as millions of people across the world fall prey to this disease with high fatality potential. In spite of tons of literature which claim that the reasons of heart attack, also called Myocardial Infraction (MI), are well known, from time to time serious questions are raised regarding the present state of knowledge about this scourge. Over weight, Obesity, Cholesterol, Saturated fat, Trans fats are all being indicted as the villains for causing MI but the ground reality is that no single factor has yet been proved conclusively that will cause the disease. This does not mean that one can violate the existing dietary guidelines evolved based on lot of scientific data and the theory of probability.

The relation between cholesterol and heart attack is well established as the former creates arterial plaques through stubborn deposits on the walls of the arteries thus narrowing down the effective diameter of the blood vessels near the heart. Logically heart needs to pump the blood with more strain in people having such plaques, determined usually by non-invasive techniques like Angiogram or scanning and such strain on the the heart is supposed to cause seizure of the cardiac muscles causing irreversible damage. World has more or less reconciled to surgical intervention like Angioplasty, heart by pass operation etc to deal with medical problems associated with atherosclerosis. Though preventive measures that include prudent dieting to exclude saturated fat, trans fats, high cholesterol containing food components in the diet and restricting red meat are well known, human weakness for rich foods and low will power to control the food intake invariably lead to atherosclerosis. There is also the genetic factor which can cause health conditions vulnerable to heart disease but still appropriate diets and physical exercise can alleviate the danger to a significant extent.

The eternal debate between carnivores and herbivores regarding the advantages of plant foods centers around the fact that red meat is a rich source of cholesterol and regular consumption of saturated fat rich meat can increase the blood cholesterol levels leading to arterial plaque build up. Though this may be factually correct, there is still some  question as to why cholesterol is not metabolized in the body as it is a biological compound necessary for fat metabolism and is produced in the body. The concept of bad cholesterol and good cholesterol is still an accepted one and the ratio of HDL (high density lipoproteins) to LDL (low density lipoproteins) is widely used to monitor the heart health by many doctors. Even this established concept is under a cloud as a result of newer studies which question this theory. In the midst of these uncertainties, one thing is sure-that by-pass surgery or Angioplasty which opens up the arteries in CVD patients do bring relief from symptoms of Angina Pectoris and extend the life span very significantly.

Latest revelation that high levels of saturated fat or cholesterol in the red meat cannot be entirely blamed for heart disease is going to put some of the present thoughts on CVD under a cloud. According to these studies saturated fat and cholesterol play a very small role in causing heart disease and the blame has to go some where else. It is averred that meat consumption causes the bacteria in the intestine of regular meat eaters to generate a lethal chemical from one of the unique amino acids present in meat called Carnitine which leads to conditions ripe for heart disease. Carnitine is a fuel for some species of microorganisms present exclusively in the intestines of carnivores and in the process they produce a lethal chemical called Trimethylamine N-oxide (TMAO) which causes the heart attack. The studies clearly brought out the connection between red meat, carnitine, bacteria, TMAO and heart attack in no uncertain terms. While vegetarians did not show any TMAO in their blood, carnivores had consistently high levels of this chemical. It is the TMAO which facilitates formation of plaques from cholesterol and in the absence of TMAO cholesterol is likely to be metabolized in the body. 

One of the outcomes of the above studies is the safety of the widely prevalent consumption of some of the products containing Carnitine which athletes and sports persons consume for enhancing their performance. While those not used to meat consumption may be relatively safe from the possibility of TMAO formation due to likely absence of TMAO forming bacteria in their guts, there is a greater chance for meat eaters to generate TMAO in their body which my have deadly consequences. Food safety authorities must frown upon the practice of the industry in marketing products containing carnitine to save precious lives!   

These observations are ground breaking in that it opens up a new avenue to tackle CVD through methods that can eliminate the bacteria which converts Carnitine to TMAO. Unfortunately so far there is no clue as to the identity of these bacteria and any antibiotic therapy can be developed only if scientists get a clue regarding their characteristics and metabolic profile. One of the species of microbes called Acinetobacter spp is reported to have the ability to form TMAO from Carnitine and Lecithin but considerable further studies only can throw more light on this area. Of course there will be many questions that will be raised about the universality of the above observations but this is going to be an area which will receive increasing attention from scientists across the world. Probably the day is not too far when meat eaters can safely eat this food with no guilt or fear of the consequences in the form of arterial diseases.  

Having praised the above studies for the new trail blazing revelations, an unbiased observer cannot help asking a simple question as to why some of the vegetarians shunning meat as well as egg are also prone to CVD though their intestine does not contain TMAO forming bacteria and they do not consume Carnitine rich foods? Beef is the richest source of Carnitine. about 100 mg per 100 gm, though pork meat also contains about one fourth to one fifth of that present in beef. As for vegetarians Milk is a minor source of this amino acid (about 2 mg per 100 ml) though it is consumed in large quantities regularly by most vegetarians. The million dollar question is whether there is another TMAO like substance in plant foods that facilitates plaque build up in them? Very inconvenient question which no body can answer for the time being! 

V.H.POTTY
http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com

THE "CALCIUM" DILEMMA-BONE VS HEART

Women and old people after the age of 60 years are prime candidates for Calcium supplements as they are considered vulnerable to bone related problems that include thin bones, brittle bones, frequent fractures, misshaped bones, osteomalacia and osteoporosis. Normally these supplements are supposed to deliver 500-800 mg Calcium per day. As Calcium is involved in formation and growth of bones, routinely these supplements are prescribed by orthopedists to many people and excess intake is not considered harmful hitherto. While high intake of Calcium is not known to be toxic, what other adverse effect it can have is a matter of conjecture with different reports indicating divergent views. Though a daily intake of 700 mg of Calcium is recommended for sound bone health, most of this requirement comes from every day foods like milk, cheese, yogurt, greens, leafy vegetables and fish with edible bones like sardines. It is believed that many older people do not get enough of this mineral increasing the risk of osteoporosis leading to thin and weak bones which can break easily, Same is true with women also at even younger ages due to hormonal changes during menopause. It is acknowledged that intake of Calcium supplements does increase bone strength but what is doubtful is whether it will really prevent fracture.

According to a recent review of some of the best scientific papers on Calcium in New Zealand, excess intake of this mineral can have other unintended consequences which calls for a re-look at the way Calcium supplements are prescribed in a routine way without realizing the long term consequences. Supplying Calcium over and above the intake through the food route can increase the risk of heart attack and strokes as increased levels of Calcium can affect the heart functions adversely, at least in some people. A study of 12000 people taking Calcium supplements, more than 500 mg per day regularly, has indicated that they faced a 30% increased chance of a heart attack during the period they took the supplement. Treatment of 1000 people with calcium supplements for a period of 5 years is estimated to cause 14 heart attacks, 10 strokes and 13 deaths but can prevent 26 fractures. also alarming is the finding that vulnerability to heart attack increased with higher dosage of Calcium supplement.Though the conclusion of the study is indeed alarming, a more careful analysis of the data indicates that out of the 12000 participants on Calcium supplement only 166 had heart attacks while 130 under the control and how significant this can be is uncertain. But qualitatively it does show the relevance or otherwise, of Calcium supplements in general, especially amongst those with even mild heart disease. As these studies were based on double-blinded controlled trials, there is no doubt about their reliability. Deciding on the risk-benefit aspects of Calcium supplements is indeed a tricky task. While bone fractures are not generally fatal, heart attacks can be and hence the dilemma for the health authorities in taking any decision.

One of the variables that has not been taken into consideration is about the complimentary effect of Vitamin D on the effect of Calcium intake as both of them are prescribed in most of the case because of the involvement of the former in bone development. Calciferol ( Vitamin D) is a critical vitamin formed under the skin from precursors already present in the body through exposure to Ultra Violet rays in the wave length range 270-300 nm and its bio-active form Calcitriol is known to reduce inflammation. Now that a shadow of doubt has been cast on the safety of Calcium supplements, it is necessary that these findings are validated through more thorough scientific studies to arrive at a reliable conclusion.

V.H.POTTY
http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com

'MILKY' WAY, THE 'HEALTHY' WAY!

Milk presents a dilemma in that a significant segment of the world population do not consume this nutrient loaded food but still seem to be apparently healthy. Many in Indian still are nostalgic about the proverbial 'Ramarajya' where milk and honey are supposed to flow freely, symbolizing the value of both these foods for keeping people happy and healthy. Unfortunately the habit of milk consumption during childhood is fast declining in the face of the relentless onslaught of modern calorie rich foods containing sugar and fat. In India per capita daily consumption of milk is about 250 gm which is an average figure, implying that some may be consuming more while others must be taking less. What are the consequences of such a paradigm shift in the eating habits of future generations on their life span and the quality of life?

Milk is traditionally associated with bone development and children are encouraged to cultivate the habit to ensure orderly growth and strong body frame. Of course Mother's milk is a category by itself providing nutrition much beyond the calcium content. Though some of the commercial products being promoted for wrong reasons deserve to be frowned upon, they at least serve the purpose of stimulating milk consumption as dry products like malted or chocolate or flavored milk powders contain milk solids and are invariably consumed with fresh milk. Recent revelations that those who had high dairy products intake when they were children were protected against stroke and other mortal diseases have reinforced the belief that milk is the best food nature has bestowed on human beings.

Thanks to food technologists milk availability has been stretched to all year round and the variety of processed products from milk has increased manifold during the last 3 decades. Products like skim milk powder, hundreds of variants of cheese and cheese based products, pro biotic yogurts and products based on them, long life packed milk with more than an year's shelf life, condensed milk preparations, traditional Indian items like paneer, khoa, chhana, shrikand, burfi, peda and many others make it possible to consume milk solids in a form consumers desire or accept. Technologies like homogenization, aseptic packing, vacuum concentration, roller drying, spray drying, freeze drying, freeze concentration, membrane filtration, reverse osmosis etc are all practiced by the dairy industry to provide the consumers with hundreds of convenient products based on milk.

According to current thinking, based on long term studies spanning almost 70 years, three servings of dairy foods in the form of liquid milk, yogurt and cheese would be adequate to derive full benefits from the nutritional strength of milk. A daily intake of 350 gm of milk can do wonders to the health of the population. The insulin like growth factor 1 (IGF-1), also known earlier as somatomedin, which is a stimulatory hormone for cell growth and multiplication, inhibiting programmed cell death and synthesis of cellular DNA, is found to be in greater concentration in the blood of population consuming milk regularly.

Milk also contains other hormones like ghrelin, leptin and several bio active molecules, some of which, in spite of being peptides pass through the digestive system, though major portion is hydrolyzed into amino acids. Medical opinion is more or less unanimous in accepting milk as suitable for preventing dental caries, increased bone mineral content, fewer bone fractures, reduced risk of protein deficiency malnutrition and rickets. The common belief that milk contributes to increased cholesterol probably will be debunked by studies across the world that chances of dying due to ischaemic stroke or heart attack are reduced significantly by 60% if milk is consumed regularly from early childhood.

V.H.POTTY
http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com