Why do I feel hungry all the time?

The food we eat is fuel for our bodies. Whenever we run low, it signals hunger, so we eat again. In this case, it is normal to feel hungry if you have not eaten for a few hours. 

However, feeling hungry all the time can be frustrating and concerning. In this article, we will examine the scientific reasons for constant hunger. If you understand these mechanisms, you will be able to better control your appetite.

What Is Hunger?

A lack of energy can cause the body to feel hungry, which prompts the urge to eat. Depending on the individual, hunger may be physical, psychological, or both. It is difficult to distinguish between real physical hunger and emotional cravings for food.

Physical Hunger:

Physical hunger occurs when the body genuinely needs nourishment. In this process, your stomach, a muscular organ, plays a key role. When you eat, your stomach expands, sending signals to your brain that you are full. Conversely, when your stomach is empty, it contracts, leading to those familiar hunger pangs. At this point, your blood sugar levels drop, and the stomach releases ghrelin, a hormone that encourages you to seek sustenance.

In biological terms, ghrelin is produced by the stomach to communicate the body’s need for food to the brain. It surges before meals and diminishes afterward. When you have sufficient energy reserves, leptin signals your brain to stop eating. 

A growling stomach and a decrease in energy levels are tangible signs of biological hunger. It may leave you feeling slightly jittery.

Psychological Hunger:

In contrast, psychological hunger is not triggered by a physiological need for nourishment. Instead, it arises from an emotional connection to certain foods, often driven by habits, stress, or environmental cues. In contrast to true hunger, emotional hunger prompts specific food cravings, usually sweet, salty, or crunchy.

This type of hunger is characterized by the absence of physical signs; you won’t experience a growling stomach or a dip in energy levels. Rather than being a physical necessity, it’s more about a desire for a particular food.

Studies indicate that emotional eating is very common, with 38% to 75% of adults reporting that they indulge in it regularly. Maintaining a balanced and healthy relationship with food requires understanding emotional hunger and separating it from physical hunger.

Why Do You Feel Hungry?

Biological causes of hunger 

Biological causes of hunger originate within the body’s physical and chemical processes. These causes can significantly influence your appetite and how often you feel hungry. Here’s a detailed explanation of each biological cause:

1. Genetics:

Hunger susceptibility is heavily influenced by our genetic makeup. Inheritance of certain genes may affect the way our bodies regulate our appetite and metabolism. 

Some people can have genes that make them more likely to feel hungry frequently, while others may have genes that make them more capable of controlling their appetites.

You can find a detailed discussion of hunger and genes in my previous post, “Does hunger mean your bariatric surgery is broken? ”

2. Blood Sugar/Insulin Dysregulation:

Hunger can be triggered by fluctuations in blood sugar levels. Blood sugar levels can spike and then plummet rapidly when you consume foods high in sugar or refined carbohydrates. This drop in blood sugar levels can send signals to your brain that you need to eat, even if you’ve recently had a meal. Pancreatic insulin regulates blood sugar levels. When insulin is dysregulated, such as in insulin resistance or prediabetes, hunger episodes become more frequent.

Researchers found that insulin plays a crucial role in regulating food intake in one study. The pancreas produces insulin to regulate blood sugar levels. Insulin levels rise when blood sugar levels are high. The hormone insulin informs the brain that food has been consumed, and it decreases appetite as a result. When blood sugar levels are low, insulin levels also fall, which can lead to feelings of hunger.

3. Gut Dysbiosis: 

Gut microbiomes are vast communities of microorganisms that live in our gut. The microbiome significantly impacts your health, including regulating hunger. 

We can suffer from an unhealthy gut microbiome if the types and quantities of microorganisms in our gut are imbalanced. When this disruption occurs, you may experience an increase in hunger and cravings, leading you to eat more calories.

4. Stress/Cortisol:

A chronic stressor, such as work, personal life, or another factor, can significantly impact your appetite. Stress releases the hormone cortisol, which influences appetite. 

Some people use stress-induced eating as a coping mechanism, resulting in overconsumption of high-fat and sugar comfort foods. Over time, this phenomenon can increase hunger and calorie intake.

Some people, however, may experience a decrease in hunger cues after bariatric surgery. The surgery can reduce the size of the stomach and intestines, which can make you feel full faster. A change in gut bacteria may also affect appetite in some people after surgery.

5. Hunger Hormones (Ghrelin, GLP-1, GIP): 

Several hormones in our body play key roles in regulating our appetite. Ghrelin, also known as the hunger hormone, is produced in the stomach and signals the brain that it is hungry. 

You feel hungry when your ghrelin levels rise. In contrast, hormones like GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic peptide) contribute to feelings of satiety and insulin secretion. When these hormones are imbalanced, hunger and fullness signals can be disrupted, resulting in persistent hunger or overeating.

Psychological Causes of Hunger: 

Hunger isn’t always about physical needs. Psychological factors can have a profound effect on our appetite and eating habits. Here are the different psychological causes of hunger:

1. Hedonic Hunger: 

The purpose of this kind of hunger is to get pleasure from eating rather than to meet a physical need. It is common for people to crave certain foods, particularly those high in fat and sugar. A craving for chocolate cake or potato chips isn’t because you need them; it’s because they bring pleasure.

Researchers found that hedonic hunger, or eating for pleasure, is linked to food addiction and obesity in university students. It was concluded that hedonic hunger may contribute to food addiction and obesity in university students. Preventing or treating these conditions may be possible with interventions that target hedonic hunger.

Bariatric surgery and Hedonic hunger

Researchers studied the effects of a very low-energy diet (VLED) or bariatric surgery on hedonic hunger and food reward after weight loss.

The study included 120 obese adults who were randomly assign to either the VLED or bariatric surgery groups. Each participant lost 10-15% of their initial body weight. The results showed a significant reduction in hedonic hunger after weight loss in both groups. However, the bariatric surgery group experienced a greater reduction in food reward than the VLED group.

The study authors concluded that bariatric surgery results in greater changes in hedonic hunger and food rewards than VLED. They suggest that this may be because bariatric surgery reduces the size of the stomach and intestines, which can lead to a decrease in the absorption of nutrients and a reduction in the release of hunger hormones.

Indirect factors such as sleep disturbances and genetics can influence a person’s eating habits and preferences. The following factors contribute to hedonic hunger:

a) Sleep Disturbances: 

Insufficient or poor-quality sleep disrupts the balance of hunger-regulating hormones, causing a rise in appetite and cravings. 

Lack of sleep causes your body to produce more ghrelin, a hormone that stimulates hunger, and less leptin, a hormone that signals fullness. This hormonal imbalance can result in increased hunger and calorie consumption.

In one study, sleep deprivation altered hormone levels that regulate appetite and metabolism, increasing hunger and reducing satiety. Additionally, sleep deprivation can also cause changes in mood and behavior, such as anxiety and stress, which can lead to unhealthy eating habits. It can also make it difficult to exercise, which contributes to weight gain.

b) Genetics (Hungry Genes):

A person’s eating behaviors and food preferences may be affect by genetic factors. Those with genetic predispositions may be more inclined to seek out and enjoy certain foods, including those that fall under the category of hedonic hunger. However, hedonic hunger cannot be determine by genetics alone. There is a complex interaction between taste preferences, psychological factors, and individual experiences.

c) Obesity

Researchers have discovered that obesity disrupts hunger and satiety mechanisms. Therefore, obese people may feel less full and have a greater desire to eat. They may also have difficulty regulating their emotions, which can lead to emotional eating.

A healthy weight is also difficult to maintain for people with obesity due to environmental barriers. These barriers include limited access to healthy food, high levels of stress, and social stigma.

ANKK1 and DRD2 gene polymorphisms have been associated with overweight, obesity, and hedonic hunger in women, according to a recent study.

Researchers found that ANKK1 rs718871 polymorphisms were associate with overweight and obesity, and DRD2 rs6277 polymorphisms were associate with hedonic hunger. Furthermore, the ANKK1 rs718871 polymorphism interacted with the DRD2 rs6277 polymorphism to increase obesity risk.

In this study, the authors concluded that ANKK1 and DRD2 gene polymorphisms contribute to obesity, overweight, and hedonic hunger in women.

2. Unprocessed Trauma:

The experience of emotional trauma can lead to emotional eating as a way of coping with unresolved feelings. People who have experienced trauma may use food to self-soothe or to distract themselves from painful memories. It is crucial to seek professional support to mitigate this type of hunger.

3. Stuck in Fight, Flight, Freeze:

A chronic state of heightened arousal, referred to as “fight or flight,” may be the result of chronic stress and trauma. Such a state can increase the perception of hunger. Due to the heightened level of stress, people may find themselves eating more frequently or excessively in this state.

4. Diet Culture Beliefs:

A culture that emphasizes calorie restriction and believes that being hungry equates to weight loss can lead to disordered eating patterns and constant hunger. 

Diets often encourage individuals to believe that hunger is a sign of progress, resulting in intentional deprivation of food, leading to increased psychological hunger and potential binge-eating episodes

5. Poor Relationship with Food:

Guilt or fear associated with food can significantly impact your eating habits and perpetuate hunger. Individuals who have experienced restrictive diets or food-related trauma may develop a negative relationship with food, causing them to overcompensate by eating more or constantly feeling hungry.

Conclusion

Hunger is a complex interplay between biological and psychological factors. Whether your hunger cues are biological or psychological, seeking counsel from healthcare professionals, registered dietitians, or therapists can help you manage your food intake. 

Each individual experiences hunger differently, and addressing the underlying causes can lead to a more balanced and fulfilling approach to eating. Understanding and addressing the factors that contribute to hunger can allow you to take control of your appetite and improve your well-being.