Warning signs of diabetes start 20 years before the actual diagnosis of the disease, Japanese researchers concluded. The study indicates early intervention and lifestyle changes can help prevent and control the condition.

A study shows people had raised fasting blood sugar levels and insulin resistance before they developed prediabetes — a pre-cursor to type 2. This study, published in The Journal of the Endocrine Society, suggests treating the illness in its early stage will help in preventing type 2 diabetes. The research monitored 27,000 non-diabetics, between the ages of 30 and 50 (mostly men). Conducted between 2005 and 2016, it studied their body mass indexes (BMIs), fasting blood sugar levels and insulin sensitivity.

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Insulin resistance causes a variety of health conditions, as the body does not respond appropriately to the hormone insulin. Also, a higher BMI is another risk factor for type 2 diabetes.

The study followed participants until diagnosis of type 2 diabetes or pre-diabetes — stage where blood sugar levels are abnormally high — or the end of 2016, whichever came first. The study period saw 1,067 new type 2 diabetes cases.

The results saw participants had increased fasting blood sugar levels and insulin resistance, along with higher BMI, up to 10 years before diagnosis. It also observed a similar pattern in those who went on to develop pre-diabetes — the same kind of warning signs but to a lesser degree about more than a decade before the diagnosis of illness.