MARY Berry can fit into the same clothes she wore 40 years ago because she's sensible. That's the awful truth. The unacceptable truth. The "for God's sake give me a second helping" truth.
At 78, her lifespan covers exactly the years during which the world first got fat, then got obese. This woman, whose life revolved around food, all day, every day, long before she became a mega TV star, is as thin as when she was a slip of a 24-year-old.
According to her -- and this is not a woman who would lie to you -- she is actually thinner now than she was in her 20s.
"I still wear the same clothes I did back then," she said this week.
Not only does Berry's life span the time during which obesity became the biggest (pardon the expression) world health problem, it covers the time during which we tried out new, different and more exciting diets every second week.
Me, particularly. I trust in God that nobody still has a copy of the Holy Faith Clontarf yearbook for my Leaving Cert year, but if they do, there, in black and white, is the obsession of my life: diets.
At 17, I was hooked on losing weight. Not as hooked as I was on gaining weight, but that's another story.
I belong in the Guinness Book of Records as the person who has tried more diets than any human being alive. Low-calorie diets were just the starter, course. Then came the grapefruit diet. The signs are still obvious. If I come across the word "grapefruit", my mouth shrivels like a burst balloon. Doesn't matter whether I hear it or see it in print.
I've done no-fat diets and -- at the other end of the scale (pardon that expression, too) -- I've done no-carb diets. I was a big pal of Dr Atkins until I discovered he weighed 18-stone when he died.
I've carried around plastic bags with chopped-up celery in them, and you can put celery up there with grapefruit as a natural product I never want to meet again as long as I live.
Before I got married, because I didn't want to look like a moving Mount Everest in the white dress, I went on the boiled egg diet. That one was based on the notion that a hard-boiled egg used up more energy to digest than it delivers, so you'd definitely lose weight if you ate nothing but them. That proved to be true. I fitted into the dress on the day. But I also ate the groom's meal as well as my own, not that he noticed as he was so nervous about giving the speech.
I could get into my wedding dress today, but during most of the intervening years I could barely fit one arm in it, I was so fat. Except when I was briefly thin, due to the latest fad diet.
Like millions of other women, I knew the Mary Berry thing. Eat small portions. Bit of soup for lunch. At dinner, eat a starter portion rather than the canoe full of food the restaurant calls a main course. Take a bit of a walk, play a bit of tennis if you can. Simple as could be, commonsensical as could be.
Why didn't we do as she did? We can't claim that food manufacturers seduced us into secret two-bag chip orgies or Ferrero Rocher frenzies. Nor can we claim that food manufacturers misled us into fad diets.
Long before Twitter, crazy diets went viral within days -- if you haven't encountered the Cabbage Soup Diet, then, sister, you don't know how lucky you are. We can't claim nutritionists didn't condemn fad diets. They did.
We just preferred the adrenalin rush of yoyo dieting to commonsense. We favoured crash-and-burn over portion control. We weren't going to listen to our elders.
Which makes it so annoying when they prove to be right -- and have a spokeswoman like Mary Berry.