Did British colonialism make South Asians prone to diabetes, cardiovascular diseases?

South Asians, especially people from India, Bangladesh and Pakistan, are six times more likely to develop type 2 diabetes compared to Europeans, according to Diabetes.co.uk. But does this have any connection to South Asian history? Medical science may have an answer.

The Indian subcontinent has a history of being subjected to famines, some of the particularly severe ones happened during the British colonial rule. The "Great Bengal Famine" in 1943 took three million lives and plagued the region with prolonged starvation.

Study provides scientific support for claims that Churchill-era British policy contributed significantly to the disaster. In 1942-43, rice stocks continued to depart India despite London's rejection of the Indian viceroy's urgent plea for more than 1 million tonnes of emergency wheat supplies. Churchill is said to have blamed the famine on Indians "breeding like rabbits" and questioned how Mahatma Gandhi was still alive despite the starvation.

So, what is the connection between the famines during British colonial era and the present day prevalence of diabetes and cardiovascular diseases among South Asians?

Dr Mubin Syed, a 56-year-old radiologist from Ohio, USA, who also works in vascular and obesity medicine, provides an explanation.

Although the lifestyle of South Asians and a number of factors are thought to be behind higher risk of diabetes, Dr Syed thinks British colonial history may be at play here too.

He recently went viral on social media for making this crucial link, reports Huffington Post.

South Asians survived at least 31 famines, especially during the 18th and 19th century. This turned them "starvation-adapted" by developing a tendency to generate and store fat instead of burning it off. This is why they have low lean muscle mass, Dr Syed explained.

Subsequent generations can be affected when their ancestors are exposed to starvation on this scale, according to research.

Dr Syed, who has been researching this area for past five years, said, "Exposure to even one famine has a multi-generational effect of causing metabolic disorders including diabetes, hyperglycemia and cardiovascular diseases. Imagine having an exposure to at least 24 major famines in a 50-year period."

"In the modern era of abundance, it becomes an evolutionary mismatch. Our adaptation to scarce food availability is no longer suitable for our environment of food abundance," he told Huffington Post.

Terming the tendency to store nutrients "an evolutionary response to famine", Dr Syed said since food scarcity is no longer a problem for much of the world at present, it creates a conflict within our physiology -- worsening our risk of diabetes and cardiovascular diseases, among other health conditions.

"It's a multifactorial perfect storm," says Dr Syed, adding that our genes that we inherited from our ancestors can explain some of these observations.

A separate study in 2016 also revealed that surviving just one famine doubles the risk of diabetes and obesity in the next generation even if they do not have to experience a famine. The risk of cardiovascular diseases also increases 2.7 times in the next generation, the study revealed.

Public health researchers at Brown University and Harbin Medical University in China studied over 3,000 local residents in China born during famine and their children gestated just afterward.

The findings revealed that people who were born during the famine between 1959 and 1961 in China had significantly higher risk of both hyperglycemia and type 2 diabetes.

Strikingly, similar observations were made in case of their children too, even though the famine had long since passed when they were born.

While genetics have a role, one must also consider one's lifestyle. To achieve the same health advantages, however, South Asians must exercise "twice as much" as Caucasians, Dr Syed commented.