It’s good to feel a little bit hungry at the start of the meal – you’ll enjoy the flavours more. But if you find yourself feeling ‘hangry’ or continuously grazing between meals then something’s awry. So how do you turn off those hunger signals? The answer could lie with your hormones.
Think ‘hormones’ and it’s likely that oestrogen, progesterone and testosterone spring to mind and their role in puberty, libido and menopause. These are the sex hormones but in fact our bodies produce over 50 others that play a critical role in our health and how we function day in day out. Two of those are ghrelin and leptin, which are involved in appetite regulation and energy balance.
Hunger vs. satiety
Ghrelin – often referred to as the “hunger hormone” – is secreted by cells in the stomach when the stomach is empty and it signals to the hypothalamus in the brain that it is time to eat. Small amounts are also released by the pancreas and the small intestine. The more ghrelin in the bloodstream, the greater the hunger signals and likely, the more food you eat. After food, ghrelin levels decrease and they don’t rise again until your body starts looking for more energy. At the same time leptin – the satiety hormone – is released to signal to your brain when you’re full.
So if you’re trying to lose weight you might be wondering how you can keep your ghrelin levels low and your leptin levels high, right? Our hormones are made for a reason - they have a specific job to do in the body. If we weren’t ever hungry, how would we know when we’re low on nourishment? Would we even take any joy from the food we eat?
It’s all about balance
The problems arise when our hormones become out of balance or our body stops responding to them. And our diet and lifestyle choices have a significant impact on this.
That doesn’t mean jumping to calorie restriction. Naturally, this will increase your ghrelin levels, potentially lead to overeating and storage of fat. Interestingly, research has shown lower fasting levels of ghrelin in individuals who are overweight, obese or morbidly obese, suggesting that over time, overeating can decrease sensitivity to the hormone, meaning we lose this essential control mechanism. This is also true of leptin. People with obesity can become leptin ‘resistant’ and their brain does not receive the message that they are full and to stop eating.
So the key to controlling your hunger hormones? It’s all about balance.
Follow these tips to help keep your hormones in check and reduce those cravings:
Eat a diet rich in fibre from fruit and vegetables, legumes and wholegrains
Fibre slows down your digestion while also keeping your gut bacteria diverse and healthy. Foods high in fibre also tend to be lower in calories and more nutrient dense meaning you get a better bang for your buck when it comes to calorie intake.
Limit your intake of high GI carbohydrates and processed foods high in sugar and artificial sweeteners
Refined and processed foods are high in calories and saturated fat and low in nutrients. As well as spiking your blood sugar for a short period, sending your hunger and energy levels on a rollercoaster, they trigger the release of dopamine, the neurotransmitter associated with reward. We start to associate that short-lived high with those sugary, baked, processed treats, as opposed to the feeling of being nourished and satiated.
Eat protein with every meal
Incorporating a portion of lean or plant protein into each meal (eggs, oily fish, organic chicken or turkey, tofu, beans and pulses) will slow gastric emptying, keeping you feeling fuller for longer. It will also blunt the insulin spike you get from eating a carbohydrate-based meal, preventing the sugar cravings that inevitably follow that initial sugar high.
Manage your stress
Studies in animals have shown that exposure to chronic stress increases circulating ghrelin and growth hormone levels (Massachusettes Institute of Technology, 2013). It also interacts with the brain’s reward pathways to increase food intake, creating a vicious cycle where we begin to see food as a comfort during times of stress and anxiety. Incorporate yoga, meditation or mindful breathing into your daily routine, get out for a walk or run in nature, or find something that works for you to allow you to live (and eat) more mindfully.
Sleep deprivation has been associated with an increase in ghrelin levels and a decrease in leptin levels, which leads to increased appetite and hunger when compared to sleeping for longer periods. Aim for 7-9 hours per night and practice good sleep hygiene by limiting screen time, avoiding heavy meals and alcohol before bed and try to stick to regular sleep and waking up times to regulate the circadian rhythm.
Research in recent years has indicated a link between High Intensity Interval Training (HIIT), reduced ghrelin and increased leptin levels. Incorporate some high intensity exercise to your lifestyle each week – circuits, sprints, cycling. Get out and get a sweat on!
If you’re looking for support with weight management, incorporating these diet and lifestyle changes is a great place to start. It’s important to remember however, that ghrelin and leptin are only two of many interrelated factors which could be impacting on your health and wellbeing.