There are some words and phrases that appear so often in the news that they're virtually guaranteed to make us switch off our brains.

“Brexit” and “Donald Trump” are the two biggest at the moment. They may be important but by now many of us are bored to tears with them. I know I am.

Now they’re being joined by a third boring but important phrase: “obesity epidemic”.

We may feel we know all about this issue already, and I’m reluctant to add to the prevailing boredom. But in the ongoing Battle of the Bulge there’s one factor that few people seem to be considering - our very complicated relationship with food.

Allow me to recap a few familiar details. Obesity is not only responsible for heart disease, strokes, type 2 diabetes and being unable to fit into an old pair of trousers. It’s also the second biggest lifestyle-related cause of cancer, after smoking.

It’s a bigger problem in Britain that in most other western European countries. Some 26 per cent of us are obese and around half of the remainder are overweight. Only Iceland and Malta are fatter than us.

Doctors, nutritionists and crusaders like Jamie Oliver want the Government to do something about it.

Others say it’s up to us as individuals. I know I could easily lose two stone without ending up dangerously underweight, thanks to a long-term relationship with beer and pizza. But if I eat a mid-morning Mars bar instead of a carrot then it’s down to me. I can’t blame the Government.

So far, so familiar. But what about the relationship between our diet and our mood?

Depression and anxiety are on the rise. That has be having an effect on what we consume.

We all know how worry and sorrow can drive people to drink. When life seems hopeless some find alcohol a quick and easy way to escape it for a couple of hours.

And “comfort eating” tends to serve a similar purpose. If you’re stressed, fretful, insecure in your jobs or relationships or struggling to make ends meet, then a glass of tap water and a lettuce leaf won’t help. A couple of beers and a big bowl of pasta might.

What I’ve noticed personally is that when I’m generally happier I do tend to eat and drink more healthily, and at lower times I’m more indulgent. I’m sure it’s common among many of us.

It feels as if, when things are getting on top of you, you don’t want to add to your troubles by being fussy about food. And in any case you deserve a treat.

You’ll put less healthy stuff on your plate, in short, when you’ve got enough on your plate.

But when things are looking up and your problems are getting solved, improve your eating and drinking can seem like the next move forward. It’s taking one step at a time.

Maybe our 21st century addiction to instant gratification plays a part too. There’s nothing necessarily wrong with wanting to save time when we live busy lives. And it’s far less time consuming to munch a packet of crisps than wait for an egg to boil, or even to eat a chocolate bar rather than wait for bread to toast and spread it with butter and jam.

There are “nudge tactics” we can deploy against obesity. In supermarkets it’s the unhealthy stuff that’s most likely to be on a special offer. When you did you last see a buy one, get one free deal on cauliflower?

Yet in search of our approval, Aldi, Asda and Waitrose have stopped selling energy drinks to under-16s, and some confectionery manufacturers are boasting of cutting the sugar levels in their products.

Back in 2016 the Cameron government suggested a 20 per cent sugar tax. but backed down after protests from the food and drink industry. The idea will probably come back some day, if the May government wasn’t so preoccupied with Brexit at the expense of everything else.

By all means let’s curb junk food advertising, make it less readily available and do whatever else we can to encourage healthy eating.

But emotions and habits can be very hard to change, and anyone who believes that it’s all down to the Government, or to self-discipline, is badly mistaken.

When I get home from work I always open the same two doors. The first is the front door. The second, only moments later, is the fridge door.

No sugar tax or official finger-wagging is going to stop that. I’ve been doing it since I was at primary school.