The WHO has said the "correlation between obesity and coronavirus mortality rates is clear". Photo / Getty Images
Covid death tolls have been fuelled by obesity, experts have said, as global research finds nine in 10 fatalities occurred in countries with a weight problem.
The study showed that New Zealand has been protected by an effective national response, despite our high rates of obesity.
Britain was found to have the third highest death rate in the world and the fourth highest obesity rate, with more than two in three adults overweight or obese.
The study by the World Obesity Federation examined almost 100 countries and found that 2.2 million of 2.5 million deaths occurred in countries with high levels of obesity. Overall, death rates were found to be 10 times higher in countries where more than half the population was overweight.
It found that not a single country with low levels of obesity had a coronavirus death rate higher than 10 per 100,000 population.
No country with death rates above 100 per 100,000 had less than 50 per cent of its population overweight.
Obesity has already been found to increase the risk of death from Covid-19 by around 50 per cent, as well as increasing the risk of severe disease, and the World Health Organisation said the report should act as a "wake-up call" for governments to tackle their nations' obesity problems.
The country with the lowest Covid death rate was Vietnam, which has one of the lowest levels of excess weight in its population, with 18 per cent overweight. Japan and Singapore were also singled out for their low levels of obesity and deaths from Covid.
In 2008, Japan introduced the "Metabo law", which requires everyone between the ages of 40 and 74 to get annual measurements of their waist circumference. Employers of those with waistlines above approved limits are required to provide weight loss classes.
The report's authors made the observation that some countries appeared as outliers.
They noted that those countries, including New Zealand and Australia, had maintained low death rates despite high obesity because of successful national responses to the pandemic.
New Zealand was listed as having 0.51 deaths per 100,000 people.
In 2016, 65 per cent of New Zealand's adult population were considered obese and we are considered a 0.0 per cent chance of meeting 2025 WHO targets for obesity.
Dr Tedros Adhanom Ghebreyesus, the director-general of the World Health Organisation, said: "This report must act as a wake-up call to governments globally. The correlation between obesity and mortality rates from Covid-19 is clear and compelling.
"Investment in public health and coordinated, international action to tackle the root causes of obesity is one of the best ways for countries to build resilience in health systems post-pandemic. We urge all countries to seize this moment."
Dr Tim Lobstein, the author of the report, senior policy adviser to the World Obesity Federation and visiting professor at the University of Sydney, said: "We now know that an overweight population is the next pandemic waiting to happen.
"Look at countries like Japan and South Korea where they have very low levels of Covid-19 deaths as well as very low levels of adult obesity. They have prioritised public health across a range of measures, including population weight, and it has paid off in the pandemic.
"Governments have been negligent and ignored the economic value of a healthy population at their peril. For the last decade they have failed to tackle obesity, despite setting themselves targets at United Nations meetings."
Johanna Ralston, the chief executive of the World Obesity Federation, said: "The failure to address the root causes of obesity over many decades is clearly responsible for hundreds of thousands of preventable deaths."
Tom Watson, the former deputy leader of the UK Labour Party, who lost eight stone and reversed type two diabetes and has become an anti-obesity campaigner, said: "This report is sobering. Again and again, public health experts shouted from the rooftops about the risks of obese populations.