Hello and welcome to more or less on the BBC World Service, with a show which likes to

shine a light on the numbers in the news and in life, and I'm Tim Haferd.

This week our attention has been drawn to these headlines.

Stark Link between obesity and Covid deaths revealed.

90% of Covid deaths are in countries with high obesity rates, study finds.

Abesity warning, as report shows 9 out of 10 Covid-19 deaths have been in countries with

high rates of obesity. World Health Organization warns report is a wake-up call to governments.

The report points out that countries with high levels of obesity, such as the US and

the UK, have suffered a large number of deaths relative to population. In contrast, skinnier

nations such as Vietnam, Japan and China have had relatively low numbers of deaths. But

does one thing lead to another? Or in stat speak, does this correlation mean that there's

causation? I turn to the Winton Professor of the Public Understanding of Risk at the University

of Cambridge in the UK. He is friend of the programme, David Schpiegelhalter.

So obesity is causing Covid deaths, it seems. What did you make of the research that has

prompted this sort of headline? Ah, not very much, in fact. It's a sort of statement

that raises the statistical suspicions. And I think it's right to be suspicious.

Abesity undoubtedly increases the risk of hospitalisation death if you catch Covid. But

mortality rates around the whole world in different countries are driven by two things.

First of all, the risk of catching it and then the risk of dying if you catch it. And obesity

doesn't really have, you know, not going to have a big effect on the risk of catching it.

And so it's all driven. If there is an association there with the risk of dying if you catch it.

Now, there's a very good calculator. I use the Alama calculator where you can put in age

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