The UK media have been full of a story which illustrates well how we are put in fear unnecessarily - and irresponsibly.
Shyam Kolvekar, a consultant heart surgeon at University College London Hospitals has said that butter should be banned to protect the nation's health. Warning of the dangers of other foods high in saturated fat, he advises people to eat less red meat, take low-fat milk and switch to olive and sunflower oil. He went on to warn that:
"Saturated fat is blamed for a third of the 200,000 premature deaths from heart disease a year. . . By banning butter and replacing it with a healthy spread the average daily sat-fat intake would be reduced by eight grams."BUT: That's not what the evidence shows!
Mr Kolvekar may be a good heart surgeon, but he is obviously not an expert in nutrition and its effects on health. In its report of this story, the BBC shows Mr Kolvekar operating on an Indian Hindu - in the UK. Indians have been using ghee (clarified butter) for centuries - without getting blocked arteries. Mr Kolvekar said when he became a consultant cardiac surgeon eight years ago the bulk of bypass operations he did were on older people. Now he is seeing people in their 40s and 50s needing triple bypasses. So are Indians eating more ghee than they did just eight years ago? Of course not!
In 1967 Dr S. L. Malhotra, reported that in Madras, the population was vegetarian, living mainly on rice.[1] The principal fat in their diet was polyunsaturated peanut oil. Malhotra compared the Madrasis with a population who lived near Udaipur in the north. Their religion allowed them to eat meat and their fat intake was almost entirely from animal sources. They cooked with ghee and had probably the highest butterfat consumption in the world.
Present-day wisdom would predict that the vegetarians would have the lower rate of heart disease, but Malhotra found the opposite: the vegetarian Madrasis had 15 times the death rate from heart attacks compared with the northern Indians even though those in Udaipur ate 9 times as much fat - and that fat was animal fat.
Twenty years later, a paper in the Lancet noted an increase in heart-attack deaths amongst the latter group.[2] By this time their diet had been made 'healthier' by replacing the traditional ghee in their diets with margarine and refined vegetable oils. This was confirmed 10 years later by a third study which found that reducing saturated fat did not reduce heart disease risk.[3]
The truth is that arteries are not blocked by eating ghee, but by adopting our 'healthy' western diet. This is backed up by many studies showing that south Asians in the UK have higher heart disease rates than they do in India.[4-5]
People who have had one heart attack are invariably told by their doctors to cut out butter and use polyunsaturated margarines instead. But there is no evidence that this will prolong their lives. Quite the opposite. As long ago as 1965 survival rates were studied in patients eating different fats and oils.[6]
In this study, patients who had already had one heart attack were assigned to one of three groups, who were given polyunsaturated corn oil, monounsaturated olive oil or saturated animal fats respectively. Blood cholesterol levels were lowered by an average of 30% in the polyunsaturated group, while there was no change in the other two groups. At first sight, therefore, it seemed that men in the polyunsaturated group had the best chance of survival. However, at the end of the two-year trial only 52% of the polyunsaturated group were still alive and free of a fresh heart attack. Those on the monounsaturated olive oil fared little better: 57% survived and had no further attack. But those eating the saturated animal fats fared the best with 75% surviving and without a further attack.
The hypothesis that saturated fats raise cholesterol and clog arteries was proposed in the 1950s, but has never been verified and confirmed - and it isn't for want of trying. There is not now, and there never has been any evidence that saturated fats are harmful in any way. In fact all the evidence points the other way. If any fats should be banned, it's the processed vegetable margarines and cooking oils.
References
1. Malhotra SL. Serum lipids, dietary factors and ischemic heart disease. Am J Clin Nutr 1967; 20: 462-475.
2. (No authors listed.) Ghee, cholesterol, and heart disease. Lancet 1987; 2: 1144-1145.
3. Singh RB, et al. Low fat intake and coronary artery disease in a population with higher prevalence of coronary artery disease: The Indian paradox. J Am Coll Nutr 1998; 17: 342-350.
4. McKeigne P M, Marmot M G, Adelstein A M, et al. Diet and risk factors for
coronary heart disease in Asians in Northeast London. Lancet 1985; ii: 1086.
5. Raheja BS. Obesity and coronary risk factors among South Asians. Lancet 1991; 337: 971.
6. Rose GA, et al. Corn oil in treatment of ischaemic heart disease. Br Med J 1965; 1: 1531-33.
