Appetite and hunger aren’t the same things. Hunger is a biological need to eat brought on by low energy levels and driven by biochemical changes, including changes in appetite hormones. With true hunger, you feel hunger pangs and your stomach growls and rumbles protesting the fact that you haven’t supplied it with food.
Appetite, on the other hand, is a psychological phenomenon. When you see food that looks appealing or has a delicious smell, you want to eat, even if you’ve just devoured a meal. The longing to eat is coming from your brain and the desire for gratification and is not a reflection of low energy stores. It’s easy to see how confusing the two and eating, when you aren’t truly hungry, can lead to weight gain.
When you’re truly hungry, appetite hormones kick into gear, letting you know it’s time to eat. Two appetite hormones you’re probably familiar with are leptin, which suppresses appetite, and ghrelin often called the “hunger hormone” due to its propensity to make you ravenously hungry. Leptin, produced by fat cells, has the opposite effect. It signals your brain that you have enough energy stores and to stop munching. Plus, it gives your metabolism a boost that helps you burn fat.
Ghrelin is secreted by the lining of your stomach and is the most powerful of the appetite hormones. When ghrelin is high, it’s hard to ignore its urgent calling telling you to keep eating. In reality, other hormones and neurotransmitters, some of them acting on your brain and others at the level of your gut, affect your level of hunger, including CCK, GIP, GLP-1, peptide YY, serotonin, and dopamine.
As you can see, the interplay between these hormones is complex and they don’t always work as they should to control your desire to eat, especially in people who are overweight or obese. The reason? People who are overweight often develop resistance to the effects of some of these hormones, the best known being leptin. If you’re leptin resistant, leptin doesn’t turn off your desire to eat even when you’ve eaten enough to replace your energy stores. Scientists believe this is partially due to the fact that fat cells produce inflammatory chemicals that block the effects of leptin.
It’s even more complicated when you look at the impact brain chemicals, such as serotonin and dopamine, have on your appetite. Dopamine turns on pleasure centers in your brain when you eat something yummy, making you feel good when you munch out on that decadent chocolate brownie. Some experts believe people who are obese have a blunted dopamine response when they eat and, therefore, keep eating past the point of satiety seeking that feeling of “reward.”
Appetite hormones work against you in another way. If you lose a significant amount of weight, your body tries to return you to your “set point” weight, the weight where it would like you to be, which isn’t necessarily the weight you WANT to be. One way it tries to restore your set point is to turn up your hunger hormones and dial down your satiety hormones, so you eat more.
Reigning In Your Appetite Hormones
If you’re trying to lose weight or maintain a new, lower body weight, it would be helpful to curb your appetite hormones. How can you best do that? There’s no magical way to silence their noise, but research suggests doing these things can help stabilize them and reduce the desire to overeat:
Eat Protein at Every Meal
As you already know, protein is the most satiating macronutrient. When you eat a high-protein meal or snack, it boosts levels of two hormones that make you feel full, GLP-1 and peptide YY. A good protein choice? Eggs. One study showed eggs, is a high-quality source of protein, were better for controlling appetite than an equal amount of protein derived from cereal. After eating a breakfast of eggs, participants had lower levels of ghrelin and higher levels of peptide YY compared to eating an equal amount of protein in cereal form. Exactly what you want after a meal! Eggs are a high-quality source of protein with all the essential amino acids.
Eat at Regular Intervals
Your body has the important job of managing energy stores. If it senses your energy supply is dwindling, hormones like leptin will drop and ghrelin will go up, a bad combination for weight control. Keep your energy level up by feeding your body the macronutrients it needs to produce energy every few hours so it doesn’t sense an energy shortage. Choose protein and fiber-rich snacks that are high in nutritional value and lower in calories. Don’t make a practice of skipping meals.
Are you getting your ZZZs? Research shows a lack of sleep elevates ghrelin and lowers leptin, a combination that increases your desire to eat. Even one night of inadequate sleep can increase your ghrelin level and your urge to snack. Lack of sleep is also linked with insulin resistance and metabolic syndrome, which can lead to weight gain and more serious health problems like heart disease and type 2-diabetes. Too many people underestimate the importance of sleep. Don’t be one of them.
Exercise not only burns calories, but it may help with leptin resistance, as long as you do it in moderation. In addition, exercise increases levels of satiety hormones, including peptide YY and GLP-1. Shorter, more intense workouts seem to best as they raise cortisol, but lower ghrelin whereas longer periods of moderate-intensity exercise raise both cortisol and ghrelin.
Cortisol also dubbed the “stress hormone” is released in response to, you guessed it, stress. Cortisol isn’t a classic appetite hormone, but it does increase hunger, particularly for foods high in sugar and fat. It also boosts muscle breakdown during times of stress and starvation so your liver can convert the amino acids to glucose your body can use for energy. In addition, higher cortisol levels longer term can promote fat redistribution with more fat storage in the waist and tummy.
Lowering cortisol is important for controlling your weight. Find a way to relieve stress – yoga, meditation or even listening to relaxing music. Exercise but don’t overtrain. Moderate amounts of exercise lowers cortisol while overdoing places enough stress on your body to increase it.
The Bottom Line
Appetite hormones are powerful chemicals that affect how much you eat and how quickly you get full.
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