Social distancing and working from home amidst pandemic have mitigated Covid-19 transmission risk. However, they have been conducive to unhealthy behaviour such as bingeing on fast food and physical inactivity.

Scientists believe the reduction in physical activity during the first few months of the pandemic could lead to an annual increase of more than 11.1 million in new cases of type 2 diabetes and result in more than 1.7 million deaths.

The estimates are presented by researchers at São Paulo State University (UNESP), Brazil, in a review article published in Frontiers in Endocrinology.

The authors stress that there is an "urgent need" to recommend physical activity during the pandemic.

Lead author Emmanuel Gomes Ciolac, a professor at UNESP's Department of Physical Education in Bauru, said: “Recent studies have shown that people with diabetes face a higher risk of developing the severe form of Covid-19, and of dying if the condition is not properly controlled.”

He added, “Others have shown that social distancing and confinement have considerably reduced levels of physical activity, increased sedentary behaviour and lowered the quality of people's nutrition.”

The study also incorporated the findings of an international online survey conducted by a group of 35 research institutions on several continents. According to the results, the level of physical activity decreased 35 per cent in the initial months of confinement. This was accompanied by a 28.6 per cent increase in sedentary behavior, such as sitting or lying for long periods, and unhealthy eating.

Previous studies had already shown that physical inactivity caused some 33 million cases of type 2 diabetes in 2019 and 5.3 million deaths in 2018.

Based on data for the period before the pandemic, the researchers estimated that the current prevalence of physical inactivity was 57.3 per cent among over-forties. And, 57.7 per cent among people at risk for diabetes, so that a lack of exercise can be considered responsible for 9.6 per cent of diabetes cases (11.1 million) and 12.5 per cent of all-cause deaths worldwide (1.7 million) if this prevalence persists for a long time.

Research also revealed that watching television or working at a computer for long hours can be bad for the health of even physically active people. Those who are required to use a computer all day for their work should get up every 30 minutes or so to stretch their legs and get whatever light exercise is possible.