Eating, overeating and obesity have become the subjects of masses of research in recent years. We don’t eat simply to fuel our bodies; there’s a complexity of psychological and physiological influences that impact our food choices. More recently, there’s been much talk about two hormones – leptin and ghrelin - nicknamed ‘the hunger hormones’.
In this short article we define what leptin and ghrelin are, how they influence hunger and what you can do to keep your levels of these crucial hormones in balance:
What are leptin and ghrelin?
Leptin is a hormone made by fat cells that decreases your appetite. Levels of leptin tend to be lower when you are slim and have a lower body fat and rise higher with increasing body weight. Some theories suggest however that people with obesity may have built up resistance to the appetite-suppressing effects of leptin.
Ghrelin is a hormone that increases appetite and has a role to play in body weight. This appetite-increasing hormone is released primarily in the stomach and is believed to send hunger signals to the brain. If someone undereats (eg anorexia nervosa) levels of ghrelin tend to increase and levels decrease along with overeating. Many researchers believe that leptin helps to regulate ghrelin.
How to keep leptin and ghrelin balanced:
Keep saturated fat balanced - A diet which is too high in saturated fat may lead to leptin resistance, meaning the body becomes less responsive to leptin’s appetite-decreasing effects, so it is important to keep fat balanced within your diet.
Focus on wholegrain carbohydrates and high quality protein - A well balanced diet that contains complex wholegrain carbohydrates (oats, rye) and high quality protein (meat, dairy, chicken, fish, nuts, seeds, beans and legumes) may help to keep ghrelin (appetite-increasing hormone) balanced.
Sleep - Sleep is crucial for keeping leptin and ghrelin balanced. In one study involving 12 young men; sleep deprivation (compared to sleeping 10 hours a night) was found to be significantly associated with an increase in ghrelin levels, hunger and appetite.
Well balanced diet & sleep are still crucial for a healthy diet
Whilst it’s useful to understand how your body responds to particular dietary and lifestyle choices, the over riding take away message is still that a well balanced diet and plenty of sleep can help to support a stable appetite and a healthy weight.