There are two hormones involved in how we regulate our body weight – Leptin and Ghrelin. Leptin decreases hunger, whilst Ghrelin increases hunger. Of course this a much simplified explanation of what actually happens, but both have a role to play in how our body reacts to food.

Leptin is made within the adipose tissues and sends signals to tell our body that we have enough fat and can stop eating. The more body fat someone has – the more Leptin there is and, in theory, the less they eat.

However, with obese individuals the system seems to go wrong. The signals to the brain are received as they should be, and the body still believes that it needs more fat. The signals may even tell your brain that you are starving. Your body becomes ‘Leptin resistant’ and the messages no longer work as they should. Therefore, up to a certain level of fat everything works as it should – beyond that – the system gets messed up and sends the wrong signals.


Ghrelin is made mainly in the stomach and it’s job is to send signals of hunger to us, making sure that we eat. Annoyingly, if we try to lose fat then the body readjusts everything making us feel hungry again. As well as increasing hunger, Ghrelin promotes the accumulation of fat. It is at its highest level just before a meal, and lowest just after.

Research shows that men and women often have varying results after dieting. Women appear to be more sensitive to Leptin than men, which seems to be a product of their specific hormones.

Some people are more sensitive to Leptin and Ghrelin than others,

This may explain why some people can lose weight and keep it off better than those who are more sensitive and are likely to regain any lost weight more easily.

There are many factors that contribute to weight loss and gain and Leptin and Ghrelin are just two of them. Other factors may include genetics, omega-3 intake (this could lead to a reduction in hunger), a lack of sleep could lead to a greater release of Ghrelin. Stress may also be linked to the amount of Ghrelin the body produces, and also sugar intake.

the effect of ghrelin on body weight_2

As we age the levels of Ghrelin may also increase

This would go some way to explaining why we tend to put on weight more easily as we get older. So, how can we take charge of Ghrelin so that it doesn’t constantly put us in ‘fat storage mode’?

1. Getting more quality sleep can help to reduce the Ghrelin levels in our bodies.

2. Reducing stress. Yes, I know this is a difficult one. We all have stress, and it is often unavoidable. However, how you deal with stress is up to you.
Try to take time out every day to de-stress. Do something that you know will make you feel better, whether that is exercise, reading or even having a relaxing bath.

3. Reducing sugar intake. Sugar is another way that Ghrelin is increased within the body. If you currently have a lot of sugary foods within your diet, it may take a few days to get out of this habit, but eventually your body won’t be demanding food as often as it used to. You will begin to feel more satisfied with less food, for longer.

Everyone is different

What may work for one person may possibly not work for another. The body is very complex and there are so many factors involved in weight loss and gain. This is why the standard ‘calorie controlled diet’ will often work at the start, and then once the body ‘catches up’, hormones are readjusted and body fat is stored again.

Connect here with WatchFit Expert Lisa Lowery-Jones

Ref: Castañeda TR, Tong J, Datta R, Culler M Tschöp MH (January 2010). “Ghrelin in the regulation of body weight and metabolism”.Frontiers in Neuroendocrinology31(1): 44–60.doi:10.1016/j.yfrne.2009.10.008.PMID19896496


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