This compares with a 3 per cent rate of CAD in rural India and a mere 1 per cent among the poor.

It’s no surprise that the culprit has been identified as diet and lifestyle. In developed countries, where cheap food tends to be high in fats and low in nutrients, it is the poor that have the highest rates of CAD. By contrast, in India, the cheapest food tends to be cereals and grains, providing an explanation for why the poor have the lowest rates of CAD.

Indian doctors have now tested two remedial diets on a thousand well-to-do CAD patients. The first diet was a version of the ‘official’ US anticholesterol diet, consisting of low-fat, low-cholesterol foods - although, in this case, slightly adapted for Indian tastebuds. The second was based on the Mediterranean diet, containing fruit, vegetables, nuts, wholegrains and soy bean oil - resulting in a high intake of alpha-linoleic acid.

The health outcomes of the two diets were dramatically different. People following the Mediterranean-type diet had half the number of adverse heart symptoms, and only 12 per cent of them died of heart attacks compared with 32 per cent of those on the low-cholesterol diet. Even by the crude measure of blood cholesterol, the Mediterranean diet scored better, with the low-fat diet paradoxically having higher cholesterol levels (Lancet, 2002; 360: 1455-61).