Why can’t I stick to my healthy eating plan? I hear this often in my coaching practice.

It’s easy to blame willpower, or the fact that we "didn’t work hard enough." But the truth is there are many factors at play.

Most healthy eating plans require calorie restriction in some way (whether that’s through reducing the amount of food eaten, or cutting down on certain food groups). Either way, we are generally eating less on a plan than we would normally.

Here’s the issue: as soon as we start to restrict food, our bodies think we are being starved. Your body interprets this food shortage as a famine and since we are biologically programmed to stay within a certain weight range (so called set-point theory), your body does everything it can to stop you from losing too much weight.

You know that insatiable hunger you feel each time you start a new diet plan? That’s not your lack of willpower. It’s because food restriction messes with your hunger hormones. You feel more hungry because your body stimulates hormones to encourage you to eat more food. At the same time your body down-regulates fullness hormones so you need to eat more food to feel full.

Alongside feeling hungrier and finding it harder to reach fullness, your brain is also programmed to notice food when it thinks it’s being starved. So your brain goes into overdrive to get your attention to eat. It’s shouting at you to eat more food.

From a psychological perspective your body also resists a drastic change in diet. Most healthy eating plans will present you with a list of “not allowed foods”, or food is given points or categorised as red, amber and green. In essence, creating a food hierarchy where some foods are thought to be better (or healthier) than others.

We find forbidden things more alluring. You know that trick when someone says don't think of a pink elephant and the first thing you think of is a pink elephant? Well it’s the same with restricted foods. When certain foods are banned, you end up wanting them more. Once they are labelled “naughty” or “bad” they become more desirable because they are forbidden.  

It’s these biological and psychological reasons that make it hard to stick to a healthy eating plan. 

So how is it possible to eat “healthy” in a way that is sustainable in the long-term, without constantly falling off the healthy eating wagon?

The secret is to focus on health promoting behaviours that have long-term positive health outcomes, noting that weight isn’t a behaviour.

These health promoting behaviours include:

• Aiming to eat a variety of food during the week, including plenty of fruit, vegetables and fibre. One tip is to think about adding food into your diet rather than subtracting. 

• Getting as much good quality sleep at night as you can (around 7-8 hours a night). Although I do acknowledge that your ability to sleep “enough” may be limited by children and/or shift work.

• Moving your body regularly - and no it doesn’t have to be high intensity or sweaty to qualify - a simple walk around the block can be just as health-promoting.

Bottom line is, there are many factors at play when your healthy eating plan doesn’t stick.  It’s all too easy to feel like you’ve failed and that it’s your fault, but it’s not your fault and your willpower isn’t the problem. This knowledge that it’s not our fault can be so freeing.

Ready to say goodbye to the binges and stress eating? Find out how in this short masterclass here.