The sensations of hunger and satiety are influenced by environmental and genetic factors, as well as specific centers of the brain – especially the hypothalamus. The hypothalamus receives signals from the gastrointestinal tract which influence eating behavior. While some neurotransmitters and hormones signal lack of food and stimulate the appetite, norepinephrine, cholecystokinin, and others increase satiety and curb cravings
What happens when you eat?
- When food enters the stomach, your body responds by sending signals to the brain via hormones.
- After a meal, Hormones such as CCK begin to rise leading to feelings of satiety
- These hormones effect the hypothalamus causing neurotransmitters such as serotonin and norepinephrine to rise, further reducing hunger
So what causes hunger?
Empty Stomach: One method that the brain uses to evaluate its energy needs is communicating with the stomach, via the vagus nerve. The stomach sends signals to the brain essentially telling the brain about its contents.
Solution: Carboxymethylcellulose expands in the stomach providing a physical feeling of fullness by giving the stomach the input it needs to tell the brain you are full. This can be a beneficial tool in attempting to learn better eating habits by making you feel full even when consuming smaller portions.
Hormones: Cholecystokinin (CCK) is a peptide hormone responsible for stimulating the digestion of fat and protein. CCK is secreted by the small intestine when we eat, triggered as a response to fat entering the duodenum, and interacts with specific neurons known to regulate appetite.
CCK levels following a meal are reduced in patients who are overweight. The reduction in CCK can result in them feeling less satisfied after a meal. Following weight loss, CCK levels don’t return to normal for up to a year – contributing to the difficulty of keeping the weight off.
Solution: L-Phenylalanine is a natural amino acid that has been proven to cause increases in CCK resulting in a feeling of satiety. (For more on L-Phenylalanine and CCK, download our white paper INFLUENCING YOUR APPETITE)
Neurotransmitters: Certain foods can have an impact on our appetite beyond just energy balance. Carbohydrates, for example, increase serotonin production resulting in a feedback loop that teaches people to reach for a snack to make themselves feel better. This is what we refer to as “emotional eating“.
Solution: 5-HTP has proved to be a useful tool in overcoming the chemical nature of appetite. By naturally increasing serotonin production, 5-HTP provides a sense of well-being and satisfaction, and decreases appetite. 5-HTP may be especially effective in reducing the over-consumption of foods used for emotional reasons.