SAMA HOOLE: Ghee. Milk fat. Curd. As much as nineteen times more fat than their southern colleagues, and nearly all of it the saturated animal fat that Ancel Keys was at that very moment teaching the West to dread.

In 1967 India ran one of the most inconvenient heart studies of the century, almost by accident, and the field has been quietly looking away from it ever since.

Dr S.L. Malhotra had a researcher's dream sitting in front of him: the Indian railway workforce, well over a million… pic.twitter.com/Vcu5TZeUPE

— Sama Hoole (@SamaHoole) June 20, 2026

In 1967 India ran one of the most inconvenient heart studies of the century, almost by accident, and the field has been quietly looking away from it ever since.

Dr S.L. Malhotra had a researcher's dream sitting in front of him: the Indian railway workforce, well over a million people. Same employer. Same medical cover. Comparable pay and hours. Scattered the length of a subcontinent. Strip all of that out and one great variable remained. Diet, which in India meant geography. In the north, in Punjab and Rajasthan and UP, the railwaymen ate the way their grandparents had. Ghee. Milk fat. Curd. As much as nineteen times more fat than their southern colleagues, and nearly all of it the saturated animal fat that Ancel Keys was at that very moment teaching the West to dread. In the south, the plate was rice, sambar, and seed oils, groundnut and sesame, with far less fat overall. By the brand-new rules being drafted in America, the southerners were the ones doing everything right. Then Malhotra counted the bodies. Heart disease deaths in the south: 135 per hundred thousand. In the ghee-soaked north: 20. Seven times the disease in the men eating the wholesome seed oils. Among the railway sweepers, the leanest and hardest-working of the lot, the gap yawned open to fifteenfold. He chased down every other explanation within reach. Smoking ran the wrong way, the north smoked more. Activity gave no clean signal. Wealth made things worse if anything, executives dropping dead while the sweepers carried on. The one thing that tracked the dying was the fat in the pan. It was published. Peer-reviewed. British Heart Journal, 1967. It landed in the exact decade the West was pouring concrete around the opposite belief. Heart associations were prescribing vegetable oils. Factories were tooling up to turn them out by the tanker. A study showing the seed-oil eaters dying seven times faster was not a study anyone with a budget wished to repeat. So nobody did. Almost sixty years on, the finding still stands, unrefuted and unloved. It has never once troubled a dietary guideline.