Do you wonder why you feel hungry all the time? Do you crave sugar first thing in the morning, and reach for snacks late into the night? Let’s take a look at the simple relationship between hunger and satiety with the help of two important hormones, ghrelin and leptin.
Hormones are the body’s chemical messengers. They work together through various endocrine pathways to send signals to the hypothalamus region of the brain. Hormonal regulation plays an extremely important role in almost all bodily functions including: achieving energy balance, promoting weight loss, initiating growth and development, immune function, metabolism, reproduction… the list goes on and on.
How do our hunger hormones work together?
In simple terms, ghrelin increases hunger and leptin satiates it. Repeat that again and again.
Ghrelin is excreted from the stomach and is thought to be an appetite stimulant. It serves as a fast acting hormone dependent on nutrition status, meal timing and meal signaling.
Here’s what you need to know about ghrelin:
- Ghrelin is an appetite stimulant.
- Fasting results in increased levels of circulating ghrelin. (help, I’m starving)
- Ghrelin is released in response to stress.
- Ghrelin levels are sensitive to food intake, rising before a meal and falling shortly after.
Recent research shows that adipose tissue (stored fat) is a highly active endocrine organ capable of secreting hormones. Unlike ghrelin, leptin travels from stored fat into the bloodstream and interacts with the hypothalamus region of the brain.
Here’s what you need to know about leptin:
- Leptin is an appetite suppressant involved in regulation of appetite and energy expenditure.
- Circulating leptin levels are correlated to the availability of stored fat. This means when stored fat increases, leptin increases, signaling adequate energy status.
- Some individuals can develop leptin resistance from long-term overfeeding. This becomes increasingly problematic with weight loss and maintenance phases.
- Leptin acts on neurons in the brain, regulating emotional and cognitive control of food intake, especially following weight loss.
- During weight loss leptin levels naturally decrease, stimulating hunger.
There’s a way to make ghrelin and leptin work for you! Here’s our view:
- Fuel with Smart foods: Reset leptin sensitivity through minimizing high fructose products, refined carbohydrates, and packaged foods. Cook as much as possible to control food quality and minimize processed ingredients and additives. If you struggle with frequent hunger pains, increase the amount of lean protein and add a healthy fat to each meal.
- Balance your plate: If you’re thinking of crash dieting and slashing carbohydrates, think twice. Since leptin is correlated to stored fat, reducing carbohydrates may backfire and depress leptin levels further. If you’re mindful of carbohydrates, implement bi-weekly fiber- rich carbohydrate refeeds which can boost lagging leptin levels.
- Schedule your sleep and manage stress: Dedicate time in your day for meditation and relaxation. Aim to get 8 hours of quality rest. Research shows that inadequate sleep increases circulating ghrelin levels and promotes feelings of hunger. For busy individuals this can sound daunting; simply try to shut down 30 minutes early for an entire week– no social media, no screen time, turn off your wifi. In that time, you should notice improved energy and willpower to fend off sugar cravings and late night snacking.
- Work hard, less often: For exercise, implement efficiency over duration. We advise short, intense activity bouts over stress promoting long-endurance events. Some suggestions include HIIT in the form of hill sprinting, heavy compound lifts, cycle sprints or kettlebell protocols.
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ASCM HIIT Exercise Guidelines