Doctor explains: How diet, sleep and gut health impact GLP-1 and weight regulation

In recent years, GLP-1-based medications such as semaglutide and liraglutide have captured global attention for their remarkable effectiveness in treating type 2 diabetes and promoting weight loss. But beyond the pharmaceutical spotlight, growing research is now linking lifestyle factors such as gut health, protein intake and sleep quality to natural regulation of GLP-1 and other hormones that influence appetite and metabolism.

To understand the science behind GLP-1, its connection to gut health and how diet and lifestyle can support its function, Firstpost spoke to Dr Pankaj Puri, Director, Gastroenterology, Fortis Escorts, Okhla (New Delhi) to shed light on the broader implications of this hormone and its role in modern metabolic health.

What exactly is GLP-1, and why is it gaining attention in both medical research and mainstream conversations around weight management?

Dr Puri: GLP-1 (Glucagon-Like Peptide-1) is a naturally occurring hormone secreted by the L-cells in the small intestine in response to food intake. It plays a key role in regulating blood glucose levels by enhancing insulin secretion, suppressing glucagon release, and slowing gastric emptying. Recently, GLP-1 receptor agonists such as semaglutide and liraglutide have garnered significant interest due to their effectiveness in promoting weight loss, improving blood sugar control in type 2 diabetes, and even showing promise in treating conditions like non-alcoholic fatty liver disease and liver fibrosis. These wide-ranging benefits have brought GLP-1 into the spotlight in both medical and mainstream circles.

Beyond medications like semaglutide or liraglutide, how can everyday habits or dietary choices naturally support GLP-1 function in the body?

Dr Puri: Several lifestyle choices can naturally boost GLP-1 levels. A balanced diet rich in protein, fibre, and unprocessed foods helps promote GLP-1 secretion. Regular exercise, quality sleep, and a healthy gut microbiome also play a role. On the other hand, ultra-processed foods and high-sugar diets may impair GLP-1 function and overall hormone balance. Nurturing gut health is key to enhancing GLP-1 activity.

What is the connection between gut health and appetite regulation? Can fermented foods and prebiotics really influence hormone levels like GLP-1?

Dr Puri: Absolutely. The gut-brain axis is central to appetite control, with hormones like GLP-1 playing a significant role in this communication. A healthy gut microbiome, supported by fibre-rich diets, fermented foods, and prebiotics promotes the release of beneficial hormones that regulate hunger and satiety. Fermented foods such as yogurt, kefir, and kimchi, along with prebiotics like garlic, onions and bananas help maintain gut diversity which in turn supports GLP-1 function.

How important is protein in regulating satiety hormones, and what are the best sources to include in a daily diet?

Dr Puri: Protein is one of the most satiating macronutrients. It triggers the release of satiety hormones such as GLP-1 and peptide YY, helping to curb appetite and reduce calorie intake. Consistently incorporating high-quality protein sources like eggs, lean meats (chicken, fish), dairy products (paneer, yogurt), legumes, and pulses into meals can help maintain appetite control and metabolic balance.

Can you explain how soluble fibre impacts digestion and appetite hormones? How much fibre should one ideally consume each day?

Dr Puri: Soluble fibre slows down gastric emptying and digestion, which prolongs feelings of fullness and stabilises blood sugar levels. It also nourishes the gut microbiome, indirectly enhancing GLP-1 activity. Good sources include oats, psyllium husk, chia seeds, and legumes. Ideally, adults should aim for at least 10–15 grams of soluble fibre daily as part of their overall dietary fibre intake (25–30 grams per day).

What role do omega-3 fatty acids and healthy fats like olive oil or avocado play in insulin sensitivity and appetite control?

Dr Puri: Omega-3 fatty acids, found in fatty fish (like salmon), walnuts, and flaxseeds, possess strong anti-inflammatory properties. By reducing systemic inflammation, they improve insulin sensitivity and metabolic function. Similarly, healthy fats such as those from olive oil and avocado help regulate satiety hormones and promote cardiovascular health, making them valuable components of a balanced diet.

How does poor sleep affect appetite hormones and glucose metabolism, and what lifestyle practices can help restore hormonal balance?

Dr Puri: Sleep deprivation disrupts key appetite-regulating hormones—namely increasing ghrelin (hunger hormone) and decreasing leptin (satiety hormone)—leading to increased cravings and risk of weight gain. Poor sleep also impairs glucose metabolism and insulin sensitivity. Restoring sleep hygiene, maintaining a consistent sleep schedule, and reducing screen time before bed can significantly help rebalance these hormones and support metabolic health.

Some studies suggest that walking after meals can aid glucose regulation. Can you elaborate on how this simple habit affects metabolic and hormonal health?

Dr Puri: Yes, walking after meals especially for 10–15 minutes can help reduce post-meal blood sugar spikes by promoting glucose uptake in muscles. It also improves insulin sensitivity and stimulates digestive processes. Incorporating this habit consistently can have a long-term positive impact on glucose control and weight management.

How do irregular meal timings or skipping breakfast impact appetite-regulating hormones like GLP-1 and ghrelin?

Dr Puri: Irregular meal patterns, including skipping breakfast, can disrupt the normal rhythm of hunger and satiety hormones. This often leads to increased ghrelin levels and reduced GLP-1 activity, triggering overeating later in the day. Adopting regular meal times and consuming a protein- and fibre-rich breakfast can help maintain hormonal balance and prevent excessive hunger throughout the day.