أَعُوذُ بِاللّٰهِ مِنَ الشَّيْطَانِ الرَّجِيمِ۔

بِسۡمِ ٱللهِ ٱلرَّحۡمَـٰنِ ٱلرَّحِيمِ

In the name of ALLAH, the Most Gracious, the Most Merciful

A 1967 Study "Ischemic Heart Disease"

A 1967 British Heart Journal study by an Indian Dr. S.L. Malhotra on 1.5 million Indian railway workers, revealed that the heart disease mortality seven times higher in South India (seed oil-based diets) than North India (ghee and dairy fats), despite controls for smoking and activity. Published amid Ancel Keys' influence on anti-saturated fat policies, the study's counterintuitive results—low disease in high-fat consumers—received limited follow-up, remaining unrefuted but absent from modern guidelines. Accompanied by a ghee image, the post aligns with the author's carnivore diet advocacy, sparking niche discussions on reevaluating seed oils' role in cardiovascular health based on this overlooked epidemiological data.

The 1967 study by Dr. S.L. Malhotra (published in the British Heart Journal) was a large-scale epidemiological analysis of ischemic heart disease (IHD, primarily coronary heart disease) mortality among Indian railway workers. It examined data from roughly 1.15–1.5 million male employees (aged 18–55) across eight railway zones in India over 1958–1962. The workforce was relatively homogeneous due to uniform national recruitment, pay scales, and job classifications, which helped control for socioeconomic and occupational differences.

Malhotra (Chief Medical Officer for the Western Railway) used official Ministry of Railways mortality returns, hospital records, ECGs, and death certificates coded under WHO’s ICD category 420 (arteriosclerotic and degenerative heart disease). Dietary patterns came from interviews, regional eating surveys (e.g., ICMR data), and observations of local habits. He cross-checked with other sources like Employees’ State Insurance morbidity data. Smoking was estimated indirectly from cigarette sales; physical activity by job type (e.g., sedentary clerks vs. active fitters/sweepers); stress via incomplete disciplinary records; and water hardness from departmental logs.

Key findings: IHD mortality showed striking regional variation—about 7 times higher in southern zones (e.g., 135 per 100,000 in Madras/Southern Railway) than northern ones (e.g., 20 per 100,000 in Punjab/Northern Railway). Southern workers also died about 8 years younger on average (mean age 44 vs. 52 in the north). Northern diets featured 8–19 times more fat (mostly saturated animal fats from ghee, milk, and fermented dairy products) plus far higher sugar intake. Southern diets were lower in total fat, relied on vegetable/seed oils (e.g., groundnut), and were rice-based with less sugar. The differences persisted despite similar age/sex distributions and after checking smoking (higher in the north), activity levels, socioeconomic status, and stress.

Malhotra explicitly rejected the then-dominant diet-heart hypothesis (pushed by Ancel Keys) that high saturated fat or sugar intake causes IHD. He argued the data pointed instead to type of fat (short-chain animal fats vs. long-chain seed oils), particle size, mastication/eating patterns, and their effects on bile flow, plasma triglycerides, and the coagulation-fibrinolysis balance.

Limitations described by the Author

Malhotra was transparent about the study’s weaknesses (all ecological/retrospective by design):

Retrospective data collection: Relied on hospital records; possible underreporting of non-hospital or sudden deaths (though he argued this bias was unlikely to differ systematically by zone).

Diagnostic variability: Differences in physician competence or record-keeping across hospitals/zones, though he believed this wouldn’t invalidate the geographical comparisons.

Proxy measures: Smoking inferred from sales data (not individual habits; ignored tobacco chewing); stress data incomplete; activity based on broad job categories.

Selected population: Limited to male government railway employees (not representative of the general Indian population, and essentially no data on women).

No individual-level diet or risk-factor data: Group-level comparisons only.

He noted: “Doubt about sudden deaths and deaths not taking place in a hospital must remain a genuine point... they are unlikely to have affected the validity of the comparison made between different zones.” Overall, he viewed the study as hypothesis-generating rather than definitive proof.

India ran the most important cardiovascular study of the 20th century by accident, and then immediately forgot about it. The study was cited periodically, acknowledged as methodologically interesting, and then set aside. In 1967, Dr. S.L. Malhotra published study's population was extraordinarily useful for research purposes: same employer, same healthcare access, comparable income and working conditions, spread across the entire country. The only meaningful variable was geography. Which meant diet.

North Indian railway workers: Punjab, Rajasthan, UP, ate a diet built around ghee and dairy fat. They consumed up to 19 times more fat than their southern counterparts. The fat was primarily saturated: clarified butter, milk fat, the short-chain saturated fatty acids that Ancel Keys had recently been telling the Western world were arterial death.

South Indian railway workers ate a diet based on rice, sambar, and seed oils: groundnut oil and sesame oil, primarily. They ate considerably less fat overall. By the standards of dietary advice being formulated in the 1960s, they should have been the healthy ones.

Heart disease mortality in South India: 135 per 100,000.

Heart disease mortality in North India: 20 per 100,000.

Seven times higher in the population eating seed oils.

Among railway sweepers specifically, the lowest-paid, most physically active workers, the gap was even wider. Heart disease was fifteen times more common in the South Indian sweeper population than in the North Indian sweeper population.

Malhotra controlled for everything he could reach: smoking, where Northerners actually smoked more. Activity levels, where the relationship was inconsistent. Socioeconomic status, where executives died more often than sweepers regardless of region. He found no variable that explained the gap except the type of fat in the diet.

The decade in which Malhotra published was the decade in which Ancel Keys's fat hypothesis was being converted into policy. The American Heart Association was issuing guidance recommending polyunsaturated vegetable oils as replacements for saturated animal fats. The food industry was producing seed oils at industrial scale. The infrastructure of seed oil promotion was being built, expensively and with great institutional momentum.

A study showing that populations eating animal fat had a fraction of the heart disease of populations eating seed oils was not, in that context, a study that anyone particularly wanted to follow up. Nobody followed up. Almost sixty years later, the finding stands unrefuted in the literature. It is not in the dietary guidelines.

Critiques “against” (pointing out flaws):

The main limitations are its observational/ecological nature (group-level correlations, not randomized or individual data), potential unmeasured confounders (e.g., genetics, other lifestyle factors, or subtle environmental differences), and lack of modern biomarkers or follow-up. It’s been called out as unable to prove causation—exactly as Malhotra acknowledged. Some modern discussions note it’s a “natural experiment” but can’t rule out unknown variables. No large-scale direct replications exist, partly because the uniform railway workforce across regions was unique.

Critiques/support “for” (or why it’s compelling):

Supporters highlight the massive sample size, the workforce’s uniformity (minimizing many confounders), and Malhotra’s systematic checking of the era’s leading hypotheses (smoking, activity, stress, SES, water hardness)—none explained the 7-fold difference. A related Malhotra analysis found no significant differences in serum lipids (cholesterol, triglycerides) between high- and low-incidence groups despite huge dietary fat contrasts. It’s frequently cited as a striking counterexample to the saturated-fat-causes-heart-disease narrative, especially in discussions of seed oils/PUFAs vs. traditional dairy fats.

Overall, it has not been formally “debunked” or refuted in the literature; it’s more often ignored or dismissed as outdated rather than disproven.

Yes, as a hypothesis-generating natural experiment, particularly in ongoing debates about dietary fats, seed oils (industrial PUFAs), and the limitations of the classic diet-heart hypothesis. It remains one of the largest and most cited pieces of evidence showing higher IHD with seed-oil-dominant diets and lower IHD with high-ghee/dairy-fat diets—opposite to what was expected in 1967 and still provocative now.

India is frequently presented as evidence that vegetarianism works. A country of 1.4 billion people, with a large vegetarian population, a tradition of plant-based eating stretching back millennia, and, the implication runs, a health profile to match. Let's look at the health profile.

India has the highest number of diabetics of any country on Earth: approximately 100 million diagnosed, with estimates suggesting a further 130 million in the pre-diabetic range. This is a population where type 2 diabetes is not a disease of the old or the obese in the Western sense: it strikes Indians at lower BMIs, at younger ages, and with more aggressive metabolic consequences than in comparable Western populations.

India has among the highest rates of cardiovascular disease in the world, again emerging at younger ages and lower body weights than typically seen elsewhere. India has significant rates of micronutrient deficiency: B12, iron, zinc, vitamin D, the precise nutrients found most abundantly in animal foods.

India also has the highest consumption of seed oils per capita of any major nation. It is the world's largest consumer of refined vegetable oils, predominantly soybean and sunflower. The vegetarian diet is the mascot. The seed oil is doing the damage. Nobody is talking about the seed oil.

India used to cook in ghee. Clarified butter, rendered slowly, shelf-stable, rich in fat-soluble vitamins and butyrate, with a smoke point suitable for the high-heat cooking that Indian cuisine requires. Ghee was Ayurvedic medicine. Ghee was considered sacred. Ghee was the cooking fat of a civilisation. Then, in the latter half of the 20th century, two things happened simultaneously: the global campaign against saturated fat reached India, and the seed oil industry, particularly soybean and sunflower oil, scaled aggressively into the Indian market.

Ghee was repositioned as unhealthy, old-fashioned, and associated with a rural past the modernising middle class was moving away from. Seed oil was modern. Scientific. Heart-healthy. The cardiologists said so. India is now the world's largest consumer of seed oils. Ghee consumption has fallen dramatically across large portions of the population, particularly in urban and middle-class households. The cardiovascular disease rates have risen in lockstep with the oil transition. The ghee is still being blamed. The sunflower oil is still being recommended. In India. In 2026.

The researches are conducted to benefit human beings and there shall always be willingness to learn from data collected during such researches. The above "data" reveals the significance of "Organic Food" which was under use at North India including "Animal Fats" six decades ago. The data from other researches may also be focused to determine effects of environmental / climatic conditions, living style and eating habits of relevant times.

Organic food refers to produce and products grown without synthetic pesticides, herbicides, or artificial fertilizers, focusing on ecological balance and biodiversity. It often includes natural, non-GMO items like honey, dry fruits, and spices, generally offering a healthier, preservative-free alternative, though it may have a shorter shelf life. These were available in abundant quantity in North India (both India and Pakistan) due to "green revolution" after Indus Water Treaty.

In these times "organic food" has emerged as a key health trend due to its superior nutritional profile, featuring higher antioxidants and essential nutrients, alongside lower pesticide residue, nitrates, and toxic metals compared to conventional options. Consuming organic food is associated with reduced risk of allergies, obesity, and chronic diseases, supporting improved overall, long-term health. The debate shall not be about cultural preferences but shall revolve around collective good of all human beings; which may indicate the food type, living conditions and life style for better livings.