Findings from a Chennai-based research team indicate that elevated cholesterol levels appeared among individuals carrying a greater genetic predisposition only when their everyday eating habits fell below nutritional standards. No meaningful difference in outcomes emerged for those whose diets were rated at a higher nutritional standard, at least not at a level the data could reliably distinguish from chance.

Drawing on a peer-reviewed PLOS ONE study of 1,020 adults, the research points to dietary patterns as a factor that can shape how genetic predispositions toward elevated cholesterol manifest in the body. Madras Diabetes Research Foundation chairperson Dr V Mohan noted that genetic makeup does not necessarily fix a person's metabolic outcomes, and that adjusting food choices may help keep cholesterol within a healthy range even among those with a strong hereditary tendency toward high levels.

Drawing on records gathered through the Chennai Urban Rural Epidemiology Study, a joint team from Madras Diabetes Research Foundation and the University of Reading examined health data covering 1,020 participants — 452 of them male and 568 female — whose ages spanned from 25 to 80. Three genetic variants spread across two genes — TCF7L2 and FTO — formed the basis of the analysis, both genes having been linked in prior research to diabetes and a range of metabolic conditions.

Each study participant was sorted into a category reflecting how many copies of the risk-linked genetic variants that individual carried. Dietary habits were evaluated through a recall questionnaire spanning the twelve months prior to assessment, alongside an Indian Diet Quality Score that drew on eight distinct food categories — among them pulses and legumes, dairy products, fruits and vegetables, white rice, cooking fats and oils, added sugar, added salt, and poultry and eggs.

Three cohorts of equal size took shape based on how participants scored across a spectrum running from poor to strong dietary habits. Among study participants eating the lowest-quality diets, those carrying a higher genetic predisposition recorded notably elevated readings for both total cholesterol and the LDL fraction — the type linked to arterial buildup — compared with counterparts whose inherited risk profile was lower.

Across both the medium-quality and high-quality diet groups, the gap fell short of statistical significance, according to Manahil M Bineid, the lead author on the study from the University of Reading. Elevated genetic risk scores also tracked with higher readings on both fasting blood glucose and HbA1c — the latter a marker reflecting average blood sugar over an extended period — and Bineid noted that these patterns underline the value of dietary choices, particularly for people of Indian descent who face a heightened baseline susceptibility to diabetes and cardiovascular disease.

Professor K S Vimaleswaran of the University of Reading noted that the findings point toward a factor within people's control, adding that while inherited genetics remain fixed, dietary patterns are open to adjustment — a diet centred on fruits, vegetables, pulses, and other nourishing foods, with restrained intake of refined carbohydrates, added sugars, salt, and unhealthy fats, represents one avenue for supporting metabolic health. The team acknowledged the work carries limitations, among them its cross-sectional design and the absence of any long-term follow-up.

The researchers noted that the study carried two methodological constraints — participant food-recall data, which is prone to inaccuracies, and a genetic score drawing on just three variants — though Dr Mohan stated that dietary improvement may hold the capacity to offset an unfavourable genetic profile.

Tailoring dietary guidance to an individual's genetic makeup and metabolic profile is an avenue that researchers believe holds promise. The team's findings point toward a future where genetic risk profiles and dietary data are assessed together, opening a pathway to more personalised nutritional guidance — though one researcher noted that practical application of this approach remains a distant prospect, even as the direction of travel is now clearer.