This is my MIL, enjoying her Campari and soda at her birthday meal yesterday. She doesn’t look 82, right? She looks younger than me, and I’m 26 years her junior. In the 32 years I’ve known her, I’ve never known her weight to fluctuate more than a pound or two. I used to think she’d won the genetic lottery, until I had two eureka moments.

The first eureka hit me like a thunderbolt. We treated her for lunch one day maybe a decade or so ago, and were excited to introduce her to a restaurant that served crispy homemade triple-cooked chips (her Kryptonite). I was really surprised when instead of ordering a portion with her smoked haddock fishcake, she ordered new potatoes and steamed broccoli. The following conversation ensued:
Me: Wow, I was sure you’d opt for the chips...they’re your favourite, right?
Her: Yes, they look delicious, but I had chips yesterday.

That simple sentence – and all it implied – was life-changing for me.

What, you’re not having chips today, because you had chips yesterday? But that was yesterday!

Astonishing as it sounds, up until that very moment, I had never realised that seemingly ‘naturally thin’ people make these sorts of micro-adjustments without conscious thought. Up to that moment, it had literally never occurred to me to not have lunch because I had (say) a buttered cheese scone for elevenses. I would never have even contemplated the idea of eating a salad for dinner because I’d had a 12” pizza for lunch. I would never have declined dessert at dinner because I’d had a slice of a colleague’s birthday cake mid-afternoon.

I didn’t make adjustments during the course of a day, when my memory of what I’d already eaten was fresh and vivid, let alone allow what I ate yesterday to influence my eating choices today.

Did people do that? Really? It was a total revelation!

After that, I paid more attention to MIL’s eating habits. It didn’t matter if all her favourite foods were lined up in a row – if she’d over-indulged a day or so before, she exercised iron willpower until she’d had a couple of counter-balancing days. Even at Christmas, birthdays or when we took her on holiday. It was an invariable pattern.

The second Eureka moment came a year or so later, when her second husband died and she came to stay with us for a couple of months while she downsized houses. The woman is a human dynamo! She never sits still! It drove me insane.

For instance, we’d all sit down to watch a movie she wanted to see, or an episode of her favourite show. Within 30 seconds, she was up getting the dog a biscuit. Two minutes later, she noticed a piece of fluff on the carpet and had to go over and pick it up. Five more minutes and she thinks it’s dark enough to close the curtains for the evening. Then she wonders if we fancy a cuppa. Back five minutes and the poor dog looks like it needs another biscuit. Or maybe it needs a pee, so she’d better walk round the garden and pull up a weed or two while it sniffs around the rose bushes. Oh, and perhaps she’d better get the watering can and water the hanging baskets so they don’t dry out.

Honest to God, it was like she had ants in her pants! She was on the go from daybreak until bedtime. Her NEAT burn must’ve been off the charts.

So that was the second Eureka moment. She was slim, seemingly without exercising, because she was constantly active.

Both revelations have had a huge impact on my approach to reaching and maintaining a healthy goal weight and lifestyle. She is the person I channel if I'm on the cusp of making a poor decision. If I look half as good as MIL when I’m 82, I’ll be pretty happy!