If you’re constantly hungry, battling 3pm cravings or considering taking GLP-1 weight-loss medications, then you need to read Dr Federica Amati’s new book, The Appetite Reset. As well as being a practical guide for those already taking GLP-1 medication without medical support (which, she says, is true of some 95 per cent of users), it’s a fascinating exploration of hunger: how our appetite is regulated, why we crave some of the foods we do, and how working with the body’s natural processes can help us feel fuller for longer and eat more healthily.
Once you understand how your appetite system works – and how our food environment influences the choices you make every day – it becomes much easier to positively change how you nourish yourself. “Patients often come in and ask for GLP-1 medication,” she says. “But often the changes I ask them to make in preparation for taking the drug start to give them some of the results they wanted after just three weeks.”
As Dr Amati writes: “What matters most is recognising that hunger is not a single signal to be controlled, ignored or overridden. It’s a complex conversation between the brain, gut, hormones, microbes, emotions and environment.”
Learning to eat in harmony with that conversation can benefit everyone, regardless of whether medication is part of the picture. Good nutrition is one of the foundations of long-term health, and when you understand how your appetite really works, establishing healthier habits becomes a whole lot easier. Here are some of the simplest ways to reset your appetite.
Understand how the appetite really works
The appetite is a four-stage system, and when each stage is activated in sequence by a nourishing meal, you will feel content and full until it’s time for the next one.
1. The sensory and anticipatory phase
“This is the stage where you think about, see, smell and interact with your food,” explains Dr Amati. “It’s when your brain starts preparing for the meal you’re about to eat. It triggers the release of saliva, increases gastric juices and primes the pancreas to release insulin.” If you’re grabbing a boxed meal, relying on meal replacement drinks, or rarely cooking from scratch, then you’re largely bypassing this first, crucial stage.
2. The oral and gastric phase
Food is chewed and then enters the stomach, where stretch receptors are activated, sending signals to the brain to reduce production of the main hunger hormone, ghrelin. As ghrelin levels fall, feelings of hunger begin to ease.
3. The intestinal phase
The next phase takes place in the small intestine. “It’s home to specialised enteroendocrine cells – hormone-producing cells that line the gut – which sense the nutrients in the food you’ve eaten before releasing hormones such as GLP-1 and PYY,” explains Dr Amati. Triggered by protein, fat and carbohydrates, these hormones slow the movement of food through the digestive system, help regulate blood sugar, and send signals to the brain that you’ve had enough to eat.
4. The colonic phase
The final stage is the colonic phase, which takes place in the large intestine and is where satiety can extend long after a meal has finished. As Dr Amati writes: “Undigested food components, particularly dietary fibre, reach the colon where they are metabolised by the gut microbiome and, in the process, microbes produce short-chain fatty acids that act as powerful signalling molecules to support gut-brain communication and the healthy functioning of gut cells. They also help sustain fullness hours after a meal.”
