Years ago I was at a comedy show in Inverness, Scotland, and remember one joke which was very funny but still cuts me to my core.

“I’m on a seafood diet,” the comedian said. “I see food, I eat it.”

I have always been on the plus side of the scale. When I was ten or eleven my father tried to help me lose a few pounds. We had a running “bet” – lose weight, he paid me, gain weight, I paid him. That arrangement ended when he realized I was manipulating the scale so that I could instantly “lose” bet...