That's an odd article. You say (and I agree) that food has become more unhealthy, but in the article he says we're consuming fewer calories than 1976. I suspect he's wrong and that (thanks in no small part to processed foods and sugary drinks) we're consuming more calories than we used to.Interesting article about how food has got more unhealthy generally, using this photo of Brighton beach in 1976 to make the point.
https://www.theguardian.com/commentisfree/2018/aug/15/age-of-obesity-shaming-overweight-people