South Asians have a disproportionately high risk of type 2 diabetes mellitus (T2DM), often developing the disease at lower body mass index (BMI) levels than Europeans. While both insulin resistance and body fat distribution are known causative agents, recent research highlights beta-cell dysfunction as a critical driver of diabetes in this population.

A new quasi-experimental study published in the journal Metabolism Open, was conducted at Christian Medical College, Vellore. This trial evaluated whether short-term weight loss could improve beta-cell function in overweight, normoglycemic adults of Indian ancestry. Twenty-three participants (median age 34 years, 74% women, average BMI 29 kg/m²) underwent a 4-week low-calorie diet intervention, including a daily meal replacement shake and lifestyle guidance.

On average, participants lost 3.5% of body weight (≈4 kg), with greater fat loss from the trunk and visceral regions compared to limbs. Dual-energy X-ray absorptiometry (DEXA) confirmed a 7% reduction in visceral adipose tissue. Glucose tolerance improved modestly, and insulin resistance (HOMA-IR) decreased significantly. The beta-cell function, which is measured by the dynamic disposition index, increased by over 120%, with data showing that every 1% drop in body weight corresponded to a 23% rise in beta-cell responsiveness.

Interestingly, these improvements occurred without significant changes in insulin sensitivity, suggesting that even modest weight reduction directly enhances beta-cell function in South Asians, possibly interrupting the vicious cycle of fat accumulation and impaired insulin secretion.

In essence, early, short-term weight loss interventions could play a vital role in diabetes prevention strategies for South Asians