In an analysis of data and studies from more than 160 countries, the researchers found that Covid-19 mortality rates increased along with countries' prevalence of obesity. They note that the link persisted even after adjusting for age and national wealth. The report found that every country where less than 40% of the population was overweight had a low Covid-19 death rate of no more than 10 people per 100,000. But in countries where more than 50% of the population was overweight, the Covid-19 death rate was much higher -- more than 100 per 100,000.