Controlling Appetite by Controlling the Ghrelin Hormone
There are many ways the body tells you that it needs nourishment. Whether your stomach grumbles, you feel lightheaded, or you start to become irritable or “hangry” — all these signals, perhaps, point to the body needing to be fed. These signals, designed for optimal health and survival, are partly controlled by the part of the brain called the hypothalamus, and also by blood glucose levels. Other factors that contribute to how well the body functions include how empty the stomach and intestines are, as well as certain hunger hormones, such as one called ghrelin. Everybody is talking about ghrelin lately; so why is this hormone important and how does it work in the body? More importantly, how can we control ghrelin to help us meet our health and weight loss goals?
What is Ghrelin?
In technical terms, ghrelin is a 28-amino acid peptide in the body that has been found to increase body weight and fat storage. In simpler terms, ghrelin is a digestive hormone that stimulates appetite. It also works to secrete growth hormone, regulates gut motility, and controls the sleep-wake rhythm as well as increased taste sensation and reward-seeking behavior. Ghrelin also regulates the conversion of glucose to energy for the body’s cells and tissues.
This hormone increases in concentration in the body when calorie intake is restricted. Ghrelin concentration seems to be twice its normal concentration before a meal, and then rapidly decreases afterwards. As we grow older, circulating levels of ghrelin and growth hormone decrease. Research shows that ghrelin may prevent sarcopenia, which is the loss of muscle mass that typically increases as a person grows older. The lower levels of ghrelin during aging may also explain why some individuals may be more at risk for insulin resistance.
Can Ghrelin levels be thrown off?
Ghrelin levels can be impacted by the way a person eats or restricts eating, as well as by body weight. As we discussed, calorie restriction can stimulate the release of ghrelin, which in turn stimulates appetite. In a similar manner, when a person suffers from an eating disorder like anorexia in which body mass index (BMI) is decreased, ghrelin levels increase. Once these individuals gain weight, ghrelin levels begin to normalize.
This being the case, it should come as no surprise that after meals, ghrelin levels are lower in obese and overweight people than they should be. Besides being affected by weight, ghrelin levels in the body can also be affected by what you eat. Keep reading to find out how you can control ghrelin levels by changing your diet.
How can Ghrelin be controlled?
Here are some ways you can modify your diet to help control ghrelin levels in the body.
Limit intake of fructose
Processed foods that contain sweeteners like fructose or high fructose corn syrup can negatively impact ghrelin levels. In fact, research shows that although dietary glucose seems to suppress ghrelin secretion, dietary fructose has less suppressive effects on ghrelin. In other words, when you consume fructose, you will feel hungrier afterwards than you would consuming glucose-containing foods. Therefore, be sure to check the label of packaged foods and drinks you consume to limit intake of fructose so you can better control ghrelin.
Consume plenty of protein each day
More meat, poultry, seafood, and plant-based proteins may help control ghrelin levels. This is because research shows that protein suppresses ghrelin levels better than fat. In turn, protein is more satiating and makes you feel less hungry after mealtime. So be sure to include a source of protein with every meal to help control ghrelin levels in the body.
Keep fatty foods balanced
You may know that fried foods are not very healthy for you, but what about healthy fats? While healthy fats are good for hormone balancing and reducing inflammation, research shows it may negatively impact ghrelin. In fact, fat decreases ghrelin levels in the body less effectively than protein or carbohydrates. Does this mean that fat is bad for you? Of course not. The body needs a balance of macronutrients for optimal health. This just means that if you consume fat, make sure you also consume some protein with it to feel more satisfied after mealtime.
Although there are no confirmed dietary supplements to help control ghrelin levels, L-cysteine is one supplement that is being researched. A 2015 study looked at the effects of L-cysteine on hunger and ghrelin levels of rodents and humans. Study results found that repeated L-cysteine administration reduced food intake in rats and reduced hunger and plasma ghrelin levels in humans. More studies will need to be done to see if this supplement could have a positive impact on hunger control in humans.
Other research on Ghrelin
There is a lot of research going on about ghrelin that may shed some light on other ways this hormone can affect the body and how you can control it. Some studies reveal that ghrelin is increased during times of stress and depression. Researchers suggest that this may be an internal mechanism in the body that works to help you cope during such difficult times. This may provide some insight into the origin of emotional-based eating behavior.
Furthermore, a 2016 study reveals that increased ghrelin levels in the body may be linked to impulsive behaviors and choice-making. In this animal study, this was depicted by the rats choosing the short-term reward rather than waiting for a larger reward. It’s unclear how this study would play out in humans but suggests that increased ghrelin levels may make it difficult for a person to avoid temptation when this hunger hormone is in effect.
There is hope however, for controlling ghrelin and in turn hunger. A 2018 study showed that ghrelin may be controlled by exercise. This animal study revealed that mice lacking a ghrelin receptor had decreased food intake following high intensity interval exercise. In other words, low ghrelin levels helped reduce food intake after exercise, which is when some of us may become more hungry than other times and in turn potentially over-consume. Other studies confirm that exercise could itself reduce hunger and food intake. Therefore, be sure to include exercise in your healthy lifestyle routine to help control hunger.
Hunger signals are vital to feeding the body when it needs energy. However, sometimes these signals can be affected in a way that makes a person hungry even when there are plenty of energy stores already available for use. This can lead to weight gain, trouble managing weight, and/or other metabolic issues that could lead to chronic disease states like heart disease and diabetes.
Therefore, it would be ideal if the hunger hormone could be controlled to prevent such issues. Although there are some ways to better control ghrelin — like eating more protein and exercising, more research still needs to be done. In the meantime, be sure to do what you can with the knowledge you now have to help keep your hunger under control and in turn be as healthy as you can be.