• Dr Sally Norton


I’ve seen it time and time again. Women come into to my surgery, desperate to lose weight, after struggling for years with diet after diet. Every time they fail at yet another crash diet or quick fix weight loss plan, they end up feeling depressed and disappointed in themselves, as if it is their fault… their own willpower that has let them down again.

But if diets actually work, then why do so many women fail on them? I’ve said it before and I’ll say it again… diets simply don’t work.

I can think of loads of reasons why diets are doomed to failure for the vast majority of us… but a study published in the Journal of Health Psychology confirmed my views on some of them. The researchers from the USA (though the stats are pretty similar this side of the pond too!) highlighted that around 1/3 of the adult population claim to be dieting at any given time, with the majority of adults having tried to lose weight at some point in their lives.

Why, then, are around 2/3rds of the population still overweight or obese? Clearly, there is a disconnect between the desire to lose weight and the ability.

In other words, deciding to lose weight is a very different matter to actually resisting that slice of cake or plate of chips.

Aside from the chemical changes, which take place in our bodies when we starve ourselves on a fad diet, or the self-esteem issues that arise from constant yo-yo dieting, this study highlighted three of my other top reasons for diet failure….

1. Deprivation doesn’t work​​

As the lead researcher, Kiviniemi, pointed out, “the deprivation experience is miserable. If you didn’t associate negative feelings with it to start, you will after a few days.” No wonder most diets fail after a week or so when life becomes so miserable that only chocolate will help. Trying to cut out foods you love just leaves you obsessing about them – wanting them even more. Instead, try simply cutting back – allowing yourself a little bit of what you fancy will stop you from feeling as though you’re depriving yourself – or swapping the foods you love for healthier swaps.

2. Willpower is overrated​​

The researchers also confirmed my view that willpower is doomed to failure. As they said, choosing to deprive yourself of something takes effort… mental energy in spadefuls.

If you have to use that energy every time you make a food choice it is going to run out…willpower is limited. So, my tip for successful weight loss is to make small healthier changes into subconscious habits that you don't have to think about….saving your willpower for occasional use!

3. You need to enjoy it to do it

If you don’t want to make those healthier changes, you won’t stick to them….so find some healthier choices you actually think are tasty. “It’s not just about eating healthy foods. It’s about eating the healthy foods you like the most.”. Healthy foods don’t have to be boring – there are plenty of healthy, yet delicious recipes out there ready for you to try.

So how can you lose weight?​​

Losing weight doesn’t have to be all about finding a quick-fix diet to drop the pounds overnight – that simply doesn’t work! Instead, it is about making small, sustainable healthy habit changes that you can enjoy…and not about depriving yourself of everything you love. A further bit of good news is that you can train your brain to enjoy healthier foods more… so it becomes even easier to make those healthy habit changes. And remember, habits can take anything from 18-254 days to become entrenched…so a bit of persistence may be required but will reap numerous benefits in the long-run!


Planning versus action: Different decision-making processes predict plans to change one’s diet versus actual dietary behavior. M Kiviniemi, C Brown-Kramer. Journal Health Psychology 2015.

How are habits formed: Modelling habit formation in the real world. P Lally, C van Jaarsveld, H Potts, J Wardle. European Journal of Social Psychology 2009.