IN THE space of less than a week, I read three front-page stories about “revolutionary” science-based diets that shield against covid-19 . Intriguingly, all three eating patterns seemed rather different to each other, despite all being published in the same newspaper. The only thing that seemed to unite them was that the proponents, helpfully, also had new diet books out.

There are dozens of “corona diets”, hailing everything from meat and ultra-low carbs to “superfoods” and veganism as ways to boost your immune system and protect you from the virus. It is a minefield. What does the evidence really say? …