Hormones and Eating Habits: Control Your Appetite
Understanding the connection between hormones, eating habits, hunger, and fullness is important for your health. To illustrate, we will discuss how brain science and hormones influence nutrition and dieting and explore the body’s systems in appetite control.
Key hormones like ghrelin, leptin, and insulin signal when we are hungry or full, and their interactions can affect how we eat. We will also look at the brain’s role in processing signals from the body and the environment that affect our feelings of hunger and fullness.
This blog explores the biology of eating behaviour as well as offering practical tips to improve eating habits. Furthermore, this information will help you manage your weight, boost your health, and better understand your body. Join us as we uncover the science of appetite control as well as learning how to apply this knowledge for better health.
Table of contents
The Enlightening Role of the Brain in Hunger and Satiety
The Hypothalamus: Control Center for Hunger
The hypothalamus is an important part of the brain that helps control hunger and how our bodies use energy. Within the hypothalamus is a section called the ventromedial hypothalamus (VMH). This area has interesting effects on eating habits, sometimes leading to unexpected results.
Studies show that damage to the VMH can cause hyperphagia, which means eating too much, or anorexia, which is a lack of appetite (Heymsfield SB, 2014). The VMH contains different types of neurons that affect eating in various ways. Some neurons make us feel hungry and encourage us to eat, while others help to stop us from eating.
This balance of signals is essential for managing our energy and responding to changes in nutrient levels and hormones. Understanding how VMH neurons work together is crucial for grasping appetite control and its connections to obesity and eating disorders.
Insular Cortex: Sensory Integration
The insular cortex is a crucial brain region that processes various sensory information, including our experiences related to eating. This area enhances our food experience by combining texture and temperature with hunger and fullness signals from our body. The insular cortex assesses sensory details to influence our eating choices, helping us decide when to start or stop. This interaction influences our food preferences and relationship with eating, highlighting the insular cortex’s role in food’s physical and emotional enjoyment.
Hormonal Signals Influencing Appetite and Eating Habits
Key Hormones in Hunger Regulation
1. Alpha Melanocyte-Stimulating Hormone (α-MSH)
Alpha-melanocyte-stimulating hormone (α-MSH) is a key molecule released from the arcuate nucleus of the hypothalamus. This hormone helps control our energy balance by reducing appetite and increasing feelings of fullness. It acts on brain receptors to reduce food intake and increase energy use, aiding in weight maintenance. α-MSH regulates appetite as part of a broader system of hormones and neuropeptides that respond to food and energy needs.
2. Agouti-Related Peptide (AgRP)
Neurons in the arcuate nucleus of the hypothalamus help control hunger by releasing a chemical called agouti-related peptide (AgRP). The body mainly releases AgRP when energy levels are low, which signals the brain to feel hungry and encourages eating. When energy supplies drop, AgRP connects to specific receptors in the brain to increase appetite and urge people to find food. This process is essential for survival, ensuring the body gets the nutrients it needs when energy is low.
3. Ghrelin
Ghrelin is known as the “hunger hormone.” It helps control appetite and energy balance. The body mainly makes ghrelin in the stomach when blood glucose levels drop. When glucose is low, ghrelin enters the bloodstream and tells the brain to trigger hunger.
This hormone affects areas of the brain, like the hypothalamus, that are important for managing appetite and energy levels. By acting on these brain regions, ghrelin makes us feel hungry and helps us anticipate mealtimes based on our eating habits. This allows the body to get ready for food intake.
Ghrelin hormone levels can change, affecting our eating habits including food choices and how much we eat. This shows how important ghrelin is to both hunger’s physical and emotional aspects.
4. Cholecystokinin (CCK)
Cholecystokinin (CCK) is a hormone made in the gastrointestinal (GI) tract. It is released when we eat fatty foods or certain proteins. The CCK hormone helps eating habits by controlling our appetite and makes us feel full. It sends signals to the brain that we have eaten enough. This hormone reduces hunger and helps release digestive enzymes and bile, which are important for breaking down and absorbing fats and proteins. Overall, CCK helps us feel satisfied after eating, preventing overeating and helping to manage our body’s energy balance.
Impacts of Processed Foods on Hunger Signals
Emulsifiers are common in processed foods and can harm the gut’s protective lining (Partridge D,2019). This damage may prevent the gut from releasing important signals that tell the brain we are full, such as cholecystokinin (CCK). When these signals don’t work properly, it can confuse the body’s natural ways of managing hunger and fullness. As a result, people might overeat because their brains don’t get the signals to indicate they are satisfied. This problem not only affects how much people eat in the moment but can also lead to long-term issues like weight gain and obesity as people continue to feel the urge to eat more than they need. Knowing how emulsifiers affect gut health highlights the need to be careful about food choices and their effects on our well-being.
The Dynamics of Insulin and Glucagon
Insulin: The Key to Glucose Regulation
Insulin is an important hormone that helps the body control blood sugar levels after eating. It is made by the beta cells in the pancreas and helps move glucose into cells, like muscle and fat cells. By doing this, insulin keeps blood sugar levels within a normal range, usually between 70 and 100 mg/dL for healthy people.
In Type 1 diabetes, the body doesn’t produce enough insulin. This results in high blood sugar levels, which can lead to hyperglycemia and serious long-term health problems if not managed. People with Type 1 diabetes need to take insulin from outside their bodies, either through injections or insulin pumps. Managing insulin is essential to controlling blood sugar levels and avoiding complications from high blood sugar, such as heart disease, nerve damage, and kidney problems.
Glucagon: The Counterpart to Insulin
Glucagon is an important hormone that helps balance the effects of insulin in the body, especially during times of fasting or low blood sugar (hypoglycemia). When blood sugar levels drop, glucagon is released from the pancreas and signals the liver to convert stored glycogen into glucose. This process, called glycogenolysis, releases glucose into the bloodstream to ensure the body has enough energy, especially for the brain.
Insulin and glucagon work together to keep energy levels stable. When blood sugar levels are high, insulin is released from the pancreas to help cells absorb glucose and store extra glucose as glycogen in the liver and muscles. When blood sugar levels fall, glucagon helps by making more glucose available. This balance between insulin and glucagon is crucial for meeting immediate energy needs and maintaining overall health.
Practical Implications and Strategies
Meal Timing and Composition
Having regular eating habits is important for controlling the ghrelin, the hormone that makes us feel hungry. Sticking to a consistent eating schedule can trigger hunger signals, helping the body prepare for food and possibly improving how well we burn calories (John Hopkins, 2022).
The order of the foods we eat—like carbohydrates, proteins, and fats—can affect how our bodies respond to glucose and insulin (UCLAhealth.org, 2024). For example, starting a meal with fibrous vegetables can help prevent large spikes in blood sugar. Their high fibre helps slow digestion and allows glucose to enter the blood gradually. This eating habit supports stable blood sugar levels and promotes better overall metabolic health, which may lower the risk of insulin hormone resistance over time.
By understanding these factors, people can make better food choices that support their health and well-being.
Exercise and Blood Sugar Management
Regular physical activity, especially Zone 2 cardio, is important for stabilizing blood sugar levels and improving insulin sensitivity (Levels.com, 2024). Zone 2 cardio includes moderate-intensity exercises like brisk walking, jogging, or cycling, where you can maintain your effort for a long time without getting too tired. This type of exercise helps improve aerobic fitness and allows your body to use fat for energy. This can lead to less dependence on glucose and better overall metabolic health.
Adding resistance training to your fitness routine can also help regulate blood sugar. You can build muscle and increase your resting metabolic rate by lifting weights or doing bodyweight exercises. This means you burn more energy even when not exercising, which can lower blood sugar levels more effectively. Together, these exercises support better glucose metabolism and reduce the risk of insulin resistance and related health issues (UCLA.org, 2021).
Conclusion
Managing hunger and fullness is a complex process that involves hormones, brain activity, and our eating habits including, what we eat. Two important hormones in this process are ghrelin, which makes us feel hungry, and leptin, which signals that we are full. Knowing how these hormones work and how they are affected by sleep, stress, and nutrition can help people make better choices about their eating habits.
What we eat plays a big role in feeling full. A diet that includes whole foods—like colourful fruits, nutritious vegetables, and whole grains—can help us feel satisfied. In contrast, highly processed foods like fast food and sugary snacks can make us hungry. Whole foods usually have more fibre and nutrients, which can help us feel full longer and keep our blood sugar steady, reducing the chances of overeating.
The brain also plays a key role in controlling hunger. It processes signals from hormones and the digestive system through various pathways, including the hypothalamus. This part of the brain helps us understand when we are hungry or full. By learning how these brain processes and hormones work, we can adopt strategies for healthier eating habits, such as being mindful of our hunger and fullness cues.
As research uncovers more about hunger and fullness, it becomes clear that our food choices greatly affect our physical and mental health. This blog aims to explain the science behind these processes and help readers take control of their health through informed food choices. By making thoughtful decisions about what we eat and understanding how our bodies work, we can develop a healthier relationship with food, leading to better health and quality of life.
References
Heymsfield SB, Avena NM, Baier L, Brantley P, Bray GA, Burnett LC, Butler MG, Driscoll DJ, Egli D, Elmquist J, Forster JL, Goldstone AP, Gourash LM, Greenway FL, Han JC, Kane JG, Leibel RL, Loos RJ, Scheimann AO, Roth CL, Seeley RJ, Sheffield V, Tauber M, Vaisse C, Wang L, Waterland RA, Wevrick R, Yanovski JA, Zinn AR. Hyperphagia: current concepts and future directions proceedings of the 2nd international conference on hyperphagia. Obesity (Silver Spring). 2014 Feb;22 Suppl 1(0 1):S1-S17. doi: 10.1002/oby.20646. PMID: 24574081; PMCID: PMC4159941.
Partridge D, Lloyd KA, Rhodes JM, Walker AW, Johnstone AM, Campbell BJ. Food additives: Assessing the impact of exposure to permitted emulsifiers on bowel and metabolic health – introducing the FADiets study. Nutr Bull. 2019 Dec;44(4):329-349. doi: 10.1111/nbu.12408. Epub 2019 Nov 25. PMID: 31866761; PMCID: PMC6899614.
Timing is everything: Why eating on a regular schedule supports overall well-being – Johns Hopkins University Student Well-Being. Jhu.edu. Published 2022. Accessed March 3, 2025. https://wellbeing.jhu.edu/blog/2022/12/09/timing-is-everything-why-eating-on-a-regular-schedule-supports-overall-well-being/
Eating in certain order helps control blood glucose. Uclahealth.org. Published April 22, 2024. Accessed March 3, 2025. https://www.uclahealth.org/news/article/eating-certain-order-helps-control-blood-glucose.
The metabolic benefits of slow, steady Zone 2 exercise | Levels. Levels.com. Published 2025. Accessed March 3, 2025. https://www.levels.com/blog/the-metabolic-benefits-of-slow-steady-zone-2-exercise
Benefits of resistance training for people with prediabetes. Uclahealth.org. Published July 12, 2021. Accessed March 3, 2025. https://www.uclahealth.org/news/article/benefits-of-resistance-training-for-people-with-prediabetes
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Medical Disclaimer
The information provided on this blog is intended for general informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay seeking it because of something you have read on this blog. The content of this blog is based on personal opinions and experiences. While every effort has been made to provide accurate and up-to-date information, no guarantees are made regarding the information’s accuracy, reliability, or completeness. Call your doctor or emergency services immediately in case of a medical emergency. Reliance on any information this blog provides is solely at your own risk.