India's Diabetes Epidemic: Tamil Nadu Hotspot Sees 104% Rise in Diabetes, 103% in Prediabetes

Dr V Mohan & Dr Soumya SwaminathanThe diabetes epidemic in India is rising rapidly. Currently, there are 101 million people with diabetes and 136 million with prediabetes in India. Tamil Nadu is one of the hotspots for the condition. According to an ICMR–INDIAB study, the prevalence of diabetes in people over the age of 20 in Tamil Nadu was 11.1% between 2008 and 2010, which increased to a 22.7% in 2022–2023, representing a 104% increase in prevalence over 10 years. Meanwhile the prevalence of prediabetes which was 12.2% during 2008–2021, rose to staggering 24.8% in 2022–2023, a 103% increase. This means there are about 12 million people who already have diabetes in TN and another 10 million who will develop it in the next few years, unless some serious steps are taken.The increase in prediabetes rates suggests that the diabetes epidemic is far from over as those with prediabetes rapidly progress to diabetes even within about four years. Moreover, the diabetes epidemic is not merely an urban phenomenon. Rates of diabetes in rural Tamil Nadu rose during the same period, from 8.3% to 18.3% which represents a 120% increase in prevalence over the same period. Thus, the rural prevalence of diabetes is rising even faster than in urban areas in Tamil Nadu.While genetic factors play a small role, it is largely driven by environmental and lifestyle-related factors of which unhealthy diet and physical inactivity play the greatest role.The recent ICMR–INDIAB study published in Nature Medicine showed that the diet of Indians in general and Tamil Nadu in particular is high in carbohydrates – constituting about 65% of total calories. The major portion comes from polished white rice which has a high glycemic index, leading to rapid blood sugar increase after a meal. The intake of protein is low (10%) against the recommended 15%–20% of calories, with quality of protein also being suboptimal.Studies from the Madras Diabetes Research Foundation have shown that excess consumption of white rice is strongly linked to type 2 diabetes and to other metabolic conditions such as obesity, dyslipidemia and fatty liver. The incidence of these are rising rapidly in the state.While the affluent have healthier food options at their disposal, those in the lower socio-economic strata of society rely heavily on the public distribution system (PDS). Under the scheme, up to 25kg of rice, 1kg of dal, 1 litre of palm oil and 5kg of sugar are provided every month for a family of five. This contributes to poor dietary diversity with people consuming mostly refined carbohydrates, and less dairy, legumes and pulses, eggs, nuts, fruits and vegetables – the drivers of the diabetes/obesity epidemic.Studies by MSSRF have shown that adolescent girls in the state have unhealthy eating habits with a higher intake of fried snacks and ultra-processed foods.If the PDS scheme is modified by increasing the amount of dal and pulses and reducing the sugar (and perhaps rice) allotted, a more balanced healthier diet can be provided to those in need. In Karnataka’s PDS system, more dal has been added and some of the rice replaced with millets.The ICMR–INDIAB study showed even a 5% reduction in carbohydrate intake (if replaced with 5% of plant proteins) can help prevent diabetes. This could be a ‘low hanging fruit’ for diabetes prevention in Tamil Nadu through governmental action.Another deficiency in diets here is inadequate fruit and vegetable (especially green leafy vegetables) intake. Fruits and vegetables are nutrient dense and loaded with antioxidants, vitamins and iron, and can help improve immunity and overall health. But due to the high cost of fruits and vegetables, consumption in Tamil Nadu is far below the three to four servings a day recommended by World Health Organization (WHO) and the National Institute of Nutrition.In this context, the Horticultural Producers’ Cooperative Marketing and Processing Society (HOPCOMS) experiment in Karnataka is worth emulating. HOPCOMS aims to support the farming community by ensuring a market for their products and making fresh fruits and vegetables accessible to city dwellers. Such a scheme where pulses, oil seeds, millets, fruits and vegetables are bought from farmers and distributed to PDS outlets within the district (as well as to schools and anganwadi centres) would benefit farmers (fair price) and consumers (quality goods at reasonable cost). If a similar scheme is adopted by the state govt it can help slowdown the epidemic of diabetes and obesity.Tamil Nadu, which is at the vanguard of public health care in India, can take the lead in control of noncommunicable diseases such as diabetes, obesity and heart disease. Tamil Nadu is lauded for its pioneering efforts in health and nutrition such as the ‘noon-meal scheme’ in schools and recently the school ‘breakfast’ scheme. By making these changes to the PDS scheme, Tamil Nadu can become a trailblazer in improving the health of its citizens, while promoting climate-resilient agriculture and increasing incomes of small farmers. This could be seen as an investment in health promotion that is likely to be cost-effective in the long term as it will save a huge amount in tertiary treatment of complications of diabetes and obesity.(Dr V Mohan is chairman of Madras Diabetes Research Foundation and Dr Soumya Swaminathan is chairperson of the M S Swaminathan Research Foundation)