We’ve all been there—you eat a good meal, but an hour later, your stomach starts rumbling again. Constant hunger can feel frustrating, and sometimes even a little confusing. Is it just cravings, or is your body trying to tell you something more? The truth is, feeling hungry all the time isn’t always about needing more food. It can be linked to your eating habits, stress, sleep, or even certain health issues. Let’s take a closer look at why this happens and how you can finally feel satisfied instead of endlessly hungry.
How the body controls appetite
There’s a constant “dialogue” between the digestive system and the brain. Muscle and fat tissue, with their satiety and hunger hormones, intervene in this “conversation.” This information is transmitted via blood and nerve fibers—this is how appetite is regulated.
Physiologically, appetite is a cyclical process that includes three main states:
- Hunger is a physiological signal from the body about the need for food.
- Satiation is a transitional feeling during a meal, when the need for food gradually decreases. It lasts about 20 minutes.
- Satiety is a stable state after eating, in which the need to eat is practically absent.
The journey from hunger to satiety takes one appetite cycle, and satiety lasts for 5–6 hours. This corresponds to the usual intervals between breakfast, lunch, and dinner.
But what if hunger sets in faster? It’s important to determine at what stage the problem occurs: too much hunger hormone, not enough nutrients, or something interfering with the proper functioning of the nervous system, intestines, and fat tissue.
12+ Reasons Why You’re Constantly Hungry
We don’t always notice habits that negatively impact our digestion and metabolism. Meanwhile, it’s our lifestyle that often creates the conditions for constant hunger. Let’s explore why it can be difficult to feel full or why hunger sets in too quickly.
1. Unhealthy diet
A balanced diet is healthy because it contains nutrients in the right quantities and proportions. Unfortunately, the modern diet can be far from ideal. How does this affect appetite?
- If there are a lot of refined carbohydrates. Is it strange that after eating baked goods, pasta, and a few rolls, you still feel hungry? Actually, it’s all quite natural. All these foods contain refined carbohydrates—carbohydrates that have been stripped of the so-called “ballast” substances—fiber. Simply put, refined carbohydrates contain “empty calories” in the form of various sugars. They satiate quickly, but not for long.
- If there’s not enough fiber. Fiber isn’t digested; it absorbs water, swells, and increases in volume, filling more of the stomach. This helps you feel full faster. Fiber continues to maintain satiety as it moves further through the intestines. Scientists from Imperial College London decided to test how fiber affects the feeling of satiety. Participants were assigned different diets—high- and low-fiber. Using special probes inserted through the nose, the scientists took samples from the ileum: before meals and every 60 minutes for 8 hours after. This allowed them to see how food affects the composition of the intestinal contents. Samples taken from people on a high-fiber diet contained more peptide YY, an intestinal hormone that helps you feel full longer.
- If you’re low on protein. Protein-rich foods stimulate the production of cholecystokinin—this intestinal “hormone” inhibits the release of new hydrochloric acid in the stomach and slows its emptying. The result is a feeling of fullness.But what kind of protein enters the gastrointestinal tract is also important, or more precisely, what amino acids it breaks down into during digestion. If you’ve decided to switch to a plant-based diet and now find yourself constantly hungry, it could be due to a leucine deficiency. This amino acid is absorbed into the bloodstream and transmits a signal of satiety to the brain.
2. Dysbacteriosis
Dysbacteriosis is an imbalance in the intestinal ecosystem. It contains over a trillion microorganisms, some of which are involved in appetite regulation.
Molecular biologist Yong Chen of Jiangnan University and his colleagues discovered that we need healthy fatty acids and beneficial gut bacteria to control our appetite. The scientists focused on specific receptors in the gut called FFAR4. These receptors appear when omega-3 fatty acids are present in the diet, such as those found in fish or nuts.
FFAR4 creates conditions for the growth of bacteroides, which secrete large amounts of pantothenate, vitamin B5. Thanks to pantothenate, the liver produces growth factor FGR21, a hormone-like substance that reaches the brain with the message “we’ve got enough sugar.” If beneficial bacteria are depleted from this chain, you’ll constantly crave sweets.
3. Rapid weight loss
In 2000, Professor of Medicine Michael Schwartz of the University of Washington (USA) and his colleagues proposed that hunger occurs when energy reserves in tissues, especially fat, are depleted, while satiety occurs when these reserves are restored. To regulate appetite, fat tissue produces its own “satiety hormone,” leptin. If energy levels are sufficient, leptin travels to the brain, reaches the hypothalamus, and activates the satiety center, which reduces appetite. During rapid weight loss, leptin levels also drop, and if fasting is also involved, the stomach begins to secrete more ghrelin.
4. Dehydration
When the body is dehydrated, the desire to drink fluids can be mistaken for hunger. The hypothalamus uses similar signals to signal thirst and hunger, making them easily confused.
The National Academies of Sciences, Engineering, and Medicine recommends drinking 2.7 to 3.7 liters of fluid per day. Men need about 15 cups of fluid, women about 11.
Want to enhance the effect? Drink green tea instead of water. The catechins in tea leaves boost the production of several intestinal hormones that suppress appetite: peptide YY, cholecystokinin, and glucagon-like peptide.
5. Chronic lack of sleep
Sleep deprivation disrupts the circadian rhythms that control the sleep-wake cycle. This disruption affects the balance of leptin and ghrelin.
Researchers from the University of Chicago found that even mild sleep deprivation alters levels of hormones that regulate hunger. Participants who slept only four hours a night for two nights experienced an 18% decrease in leptin levels and a 28% increase in ghrelin levels. Additionally, taste preferences changed, leading to a constant craving for sweet and salty foods.
6. Stress
A constant desire to eat is a classic response to chronic stress. The body perceives you’re in danger and stocks up on provisions. This process is driven by cortisol, an adrenal hormone that helps us survive prolonged stress, but to do so, it adjusts metabolism and forces us to consume calorie-dense foods. With chronic stress, the increase in appetite can be persistent, leading to “stress eating”.
7. Excessive physical activity
Physical activity burns calories and can increase hunger—the body’s way of signaling the need to replenish expended energy. This is especially true during high-intensity workouts that cause sweating and shortness of breath. Such exercise often triggers a constant craving for food, which is not a bad thing if your goal is to gain muscle mass. However, you need to satisfy your hunger with the right foods.
8. Diet soda
Paradoxically, diet drinks don’t promote weight loss; on the contrary, they actually increase appetite and lead to weight gain. This is partly due to the fact that diet products use sweeteners instead of glucose. Artificial sweeteners, such as sucralose, which is 600 times sweeter than table sugar, overstimulate the brain’s pleasure center without affecting the satiety center. This leads to increased appetite.
Researchers from the University of Southern California discovered that sucralose can make our brains feel hungrier. The study involved 75 people aged 18 to 35, who were given a choice of a drink containing sucralose, sucrose (table sugar), or water for three days. The intervals between sessions ranged from two days to two months, and the drinks were randomly assigned to the participants. Those who consumed sucralose did not experience a surge in insulin or the hormone GLP-1.
Study leader Kathleen Alanna Page explains, “The body uses these hormones to tell the brain that you’ve consumed calories, thereby reducing hunger. But sucralose doesn’t stimulate their production.” This is why some sweets still make you hungry.
9. Premenstrual syndrome
Premenstrual syndrome (PMS) is not a myth, but a real menstrual cycle disorder that affects 9 out of 10 women. PMS manifests itself with various unpleasant symptoms approximately a week before menstruation. It is precisely during this time that a strong desire for sweet and salty foods often appears, which is believed to be a consequence of a lack of serotonin, or the “happiness hormone”.
10. Nicotine withdrawal
Not everyone knows, but when trying to smoke less, less frequently, or quit smoking completely, you experience more than just withdrawal symptoms—the urge to smoke. Increased appetite is one of the symptoms of nicotine withdrawal. This syndrome occurs because the body experiences an acute shortage of nicotine, which dulls the appetite. When you quit smoking, many nicotine-sensitive receptors “wake up,” and with them comes a constant craving for food. It takes some time for the number of receptors to return to normal, making appetite control easier.
11. Boredom
Psychologists identify “emotional hunger,” which occurs because a person needs to calm down. And food, especially sweets, triggers the release of pleasure hormones. If you eat to relieve stress every time someone makes you nervous, the habit becomes ingrained, and you become constantly hungry.
Before opening the fridge or cupboard, take a deep breath and ask yourself, “Am I really hungry?” Try to distract yourself. Do something else, like read or take a walk. If your hunger is false, you’ll soon forget about it.
12. The habit of eating while watching TV
Although appetite is regulated by the endocrine system, our attention also plays a significant role. Scattered eating doesn’t create clear memories of the meal, so even after eating, you still want to eat something more tasty.
13. Advertising
Marcus Gavius Apicius, a Roman gourmand, said, “We eat with our eyes.” Indeed, our ancestors relied on sight to find food, and a strong connection developed in the brain: when we see a juicy, bright berry or red, roasted meat, a chain of reactions is triggered, and we want to eat.
There is even a hypothesis according to which, during the course of evolution, humans developed color vision—the ability to see red, green, and blue—so that they could easily find colored berries among the dark green foliage.
Now remember the colors of the logos of famous soda and fast food brands? That’s right, mostly red, orange, or yellow. Images of food have the same effect on the brain; it doesn’t even care that it’s “virtual” food—hunger becomes very real, even if you’ve eaten very recently.
What to do if you constantly feel hungry
Start simple: go to bed earlier, increase your water intake, and adjust your diet.
The best way to maintain appetite control is to eat a properly balanced diet of carbohydrates, proteins, and fats. If food provides the body with the energy it needs, you’re less likely to overeat or snack constantly. A well-fed body is more resilient to stress and less likely to lose control.
To feel full longer without overeating:
- Include fiber in your diet regularly.
- prepare dinner from protein products;
- Don’t eliminate fats, but switch to healthy ones;
- control portion size;
- Eat according to the regimen.
To avoid distractions, Harvard Medical School experts also recommend:
- Eat with your non-dominant hand – If you are right-handed, hold your fork in your left hand when bringing food to your mouth.
- Use chopsticks instead of a fork and knife.
- Think about what it took to make this dish, from the sun’s rays to the work of the farmer and the cook.