Ghrelin: The Hunger Hormone and Its Role in Weight Gain

Have you ever wondered why some days you feel hungrier than others — even after eating? The answer often lies in a hormone called ghrelin, also known as the “hunger hormone.” Ghrelin plays a major role in regulating appetite, weight gain, and even how your body responds to dieting. Understanding how ghrelin works can shed light on why weight loss is difficult for many people and why bariatric surgery can be such an effective tool.

At BASS Bariatric Surgery & Weight Management, we often hear patients ask: “Why am I always hungry?” or “Is my metabolism working against me?” Ghrelin is one of the key players behind those feelings.

What Is Ghrelin?

Ghrelin is a hormone produced mainly in the stomach. Its primary function is to signal to your brain that it’s time to eat. Think of ghrelin as your body’s internal “hunger alarm.” When your stomach is empty, ghrelin levels rise, telling your brain to seek food. Once you eat, ghrelin levels drop, and your hunger decreases.

Key functions of ghrelin include:

• Stimulating appetite and food intake
• Promoting fat storage in the body
• Influencing metabolism and energy balance
• Affecting sleep, mood, and even gastrointestinal motility

Ghrelin and Weight Gain

High ghrelin levels can make weight loss more difficult. When you diet or cut calories, ghrelin production often increases, making you feel hungrier. This is one reason why so many people regain weight after dieting — the body naturally pushes back by producing more hunger signals.

Research shows:

• People with obesity often have abnormal ghrelin regulation, meaning their bodies may not suppress ghrelin as effectively after meals.
• Chronic dieting can actually increase ghrelin production, making long-term weight loss even harder.

How Bariatric Surgery Affects Ghrelin

One of the reasons bariatric surgery is so effective is that it doesn’t just limit how much food you can eat — it also changes hormone levels, including ghrelin.

• Sleeve Gastrectomy: Removes about 80% of the stomach, including the part that produces most ghrelin. This leads to a dramatic reduction in hunger.
• Gastric Bypass: Alters digestion and changes hormone signaling in ways that lower ghrelin and increase satiety hormones like GLP-1 and PYY.
• Gastric Band: Restricts food intake but does not significantly impact ghrelin levels, which is partly why it produces less dramatic results.

This hormonal effect is why many patients notice reduced hunger immediately after surgery — even before major weight loss occurs.

Can You Naturally Lower Ghrelin?

While surgery has the strongest impact, some lifestyle changes can help regulate ghrelin levels:

• Eat protein-rich meals: Protein helps reduce ghrelin more effectively than carbs or fats.
• Prioritize sleep: Poor sleep raises ghrelin, making you hungrier the next day.
• Manage stress: High stress increases ghrelin production, leading to emotional eating.
• Stick to regular meals: Skipping meals can spike ghrelin, causing overeating later.

Still, for patients with obesity, these lifestyle changes may not be enough, which is why surgical options are often considered.

FAQs About Ghrelin and Hunger

Does ghrelin make you gain weight?‍

Not directly — but high ghrelin levels increase appetite and cravings, which can lead to overeating and weight gain.

Why am I always hungry even after eating?‍

Your ghrelin levels may not be dropping as they should. Some people have difficulty suppressing ghrelin after meals, which can contribute to ongoing hunger.

Does bariatric surgery cure hunger?‍

Surgery significantly reduces ghrelin levels, especially gastric sleeve, but hunger can return over time. Long-term success requires healthy eating habits and follow-up care.

Taking Control of Hunger Hormones

Ghrelin is a powerful hormone that plays a major role in weight management. For many people struggling with obesity, hunger isn’t just about willpower — it’s about biology. Bariatric surgery changes how ghrelin works in the body, making weight loss and diabetes control much more achievable.

At BASS Bariatric Surgery Center, our surgeons — Dr. Brian Chin and Dr. Jason Moy — specialize in procedures that address both the physical and hormonal causes of obesity. If you’re struggling with constant hunger and weight challenges, bariatric surgery may be the solution.

Serving Walnut Creek, Brentwood, and the East Bay
Call 925-940-1052 or request a consultation today.