Why hormones might be putting the brakes on your weight loss

Struggling to lose weight and keep it off? Turns out your hormones could be to blame. Learn why – and what to do about it.

If you’ve ever tried to lose weight and couldn’t make the results stick, you’re not alone – as many as four out of five people who shed some kilograms put them back on again, and sometimes more.

The question is why?

Meet your ‘hunger hormones’

“We have at least nine hormones that suppress hunger, and leptin is the most powerful,” says Professor Joseph Proietto, head of Austin Health’s Weight Control Clinic at the University of Melbourne.

Meanwhile, other hormones like ghrelin have the opposite effect, working to make us hungry.

And losing weight is scientifically proven to throw a spanner in how those hormones work.

“After weight loss, nearly all of the hunger-suppressing hormones are lower, which leads to increased hunger,” says Prof Proietto.

“And we’ve shown they’re still lower three years later. Likewise, ghrelin goes up after weight loss, and stays up for at least three years.”

It’s a fact that fuels weight regain and can make future weight-loss attempts more challenging, too.

How to harness your hormones

There are things you can do to help your hormones work for, rather than against, your weight-loss efforts.

1.     Quit the crash diets

Obesity researcher Dr Nick Fuller, of University of Sydney’s Charles Perkins Centre, says crash diets cause a significant, sharp shift in appetite hormones, telling you to eat more.

“Plus, when you dramatically restrict the amount of food you eat, the level of the stress hormone cortisol increases, which also leads to weight gain,” says Dr Fuller.

The alternative? Slow weight loss – no more than 2kg a month.

Dr Fuller advocates taking weight-loss breaks every second month, a method known as interval weight loss.

“This interval weight loss prevents the fight-or-flight response to losing weight that you usually witness – the decrease in metabolism and change in appetite hormones. As a result, you’re able to not only lose weight, but keep it off,” he explains.

2.     Make sleep a priority

You’ll eat more when you’re tired, and it’s all down to the hormonal shift losing sleep causes.

A University of Chicago study found sleep loss decreased leptin by 18 per cent and bumped up ghrelin by 28 per cent.

As a result, as study participants’ sleep time fell, their appetites rose and the foods they were drawn to, changed. Sweet, salty and starchy foods were more appealing than ever.

Different research shows between seven and nine hours of sleep a night is the sweet spot for weight loss.

3.     Stress less

Not only do 70 per cent of us use food as a stress-management strategy, stress makes us more likely to choose higher-fat, higher-sugar foods, too.

It’s because they suppress the release of cortisol, so essentially, eating is a way of self-medicating.

The fix is dialling your stress levels down, which can be as simple as spending some time outdoors.

A 2019 study found that as little as 20 minutes sitting or walking in nature significantly lowers cortisol levels.

4.     Get physical.

While tweaking what you eat produces better weight loss than exercising, research also shows that heart-pumping physical activity suppresses hunger levels by affecting the release of ghrelin and another key appetite hormone called peptide YY.

5.     Unfollow those ‘foodie’ accounts

Feel hungry after seeing something delicious on your social media feed, even if you’ve just eaten?

You’re not imagining it. Research shows that ghrelin levels increase simply as a result of eyeballing images of food.

Written by Karen Fittall.