The type of foods you’re eating plays a big part.

By Dr Emma Davies

Published: Thursday, 13 July 2023 at 12:00 am


Do you still feel peckish post-lunch? It could be that you’re eating too many high-sugar foods, which readily release glucose in the body. This causes a spike in insulin and a subsequent drop in blood sugar levels, which can leave you craving more of the same. Foods rich in protein and fibre take longer to digest, leaving you feeling full for longer.

The metabolic hormones leptin and ghrelin also play a role in your hunger. Leptin is a hormone made by fat cells that regulate hunger by providing a sensation of feeling full.

Meanwhile, ghrelin, known as the hunger hormone, is released primarily in the upper part of the stomach and tells your brain when you’re hungry. Ghrelin levels are generally high just before eating, and low after.

But everyone is different and a number of factors affect how well the hormone system works. For instance, obesity can cause a lack of sensitivity to leptin, which can result in you feeling hungry even after eating. Prolonged periods of dieting can further weaken the satiety hormone response.

Sleep makes a big difference to hunger levels. For example, a Swedish study in 2022 showed that just one night of sleep deprivation led to lower levels of leptin and higher levels of ghrelin. The changes in leptin following sleep loss were more pronounced among women and the ghrelin increase was stronger in those with obesity.

Lack of sleep can lead to a strong desire to consume high-reward foods such as sugar-laden treats.

You could try eating a handful of nuts as part of your meal to stave off hunger pangs. In 2022, a study suggested that eating Brazil nuts daily for eight weeks caused lower levels of ghrelin after eating, potentially decreasing hunger.

Why do I always have room for dessert?

If you’re considering adding dessert to sate your hunger, consider that MRI imaging has shown that reward centres in the brain light up at the prospect of sweet treats, with some people being more sensitive than others.

You may subconsciously crave this response and override your sensation of being full from your main course.

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Asked by: Elinor Boese, Berkshire

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