14 Reasons Why You're Always Hungry
When you're hungry, your stomach may "growl" and feel empty, or you may get a headache, feel irritable, or be unable to concentrate.
Most people can go several hours between meals before feeling hungry again, though this isn't the case for everyone.
There are several possible explanations for this, including a diet that lacks protein, fat, or fiber, as well as excessive stress or dehydration.
This article discusses 14 reasons for excessive hunger.
1. You’re Not Eating Enough Protein
Consuming enough protein is important for appetite control.
Protein has hunger-reducing properties that may help you automatically consume fewer calories during the day. It works by increasing the production of hormones that signal fullness and reducing the levels of hormones that stimulate hunger (1Trusted Source, 2Trusted Source, 3Trusted Source, 4Trusted Source).
Due to these effects, you may feel hungry frequently if you're not eating enough protein.
In one study, 14 men with excess weight who consumed 25% of their calories from protein for 12 weeks experienced a 50% reduction in their desire for late-night snacking, compared with a group that consumed less protein (5Trusted Source).
Additionally, those with a higher protein intake reported greater fullness throughout the day and fewer obsessive thoughts about food (5Trusted Source).
Many different foods are high in protein, so it's not difficult to get enough of it through your diet. Including a source of protein in every meal can help prevent excessive hunger.
Animal products, such as meat, poultry, fish, and eggs, contain high amounts of protein.
This nutrient is also found in some dairy products, including milk and yogurt, as well as a few plant-based foods like legumes, nuts, seeds, and whole grains.
Protein plays an important role in appetite control by regulating your hunger hormones. For this reason, you may feel hungry frequently if you don't eat enough of it.
2. You’re Not Sleeping Enough
Getting adequate sleep is extremely important for your health.
Sleep is required for the proper functioning of your brain and immune system, and getting enough of it is associated with a lower risk of several chronic illnesses, including heart disease and cancer (6Trusted Source).
Additionally, sleeping enough is a factor in appetite control, as it helps regulate ghrelin, the appetite-stimulating hormone. Lack of sleep leads to higher ghrelin levels, which is why you may feel hungrier when you are sleep deprived (7Trusted Source, 8Trusted Source).
In one study, 15 people who were sleep deprived for only 1 night reported being significantly more hungry and chose 14% larger portion sizes, compared with a group that slept for 8 hours (9Trusted Source).
To keep your hunger levels under control, it's generally recommended to get at least 8 hours of uninterrupted sleep each night.
Sleep deprivation is known to cause fluctuations in your hunger hormone levels and may leave you feeling hungry more frequently.
3. You’re Eating Too Many Refined Carbs
Refined carbs have been processed and stripped of their fiber, vitamins, and minerals.
One of the most popular sources of refined carbs is white flour, which is found in many grain-based foods like bread and pasta. Foods like soda, candy, and baked goods, which are made with processed sugars, are also considered to be refined carbs.
Since refined carbs lack filling fiber, your body digests them very quickly. This is a major reason why you may be hungry frequently if you eat a lot of refined carbs, as they do not promote significant feelings of fullness (10Trusted Source).
Furthermore, eating refined carbs may lead to rapid spikes in your blood sugar. This leads to increased levels of insulin, a hormone responsible for transporting sugar into your cells (10Trusted Source, 11Trusted Source).
When a lot of insulin is released at once in response to high blood sugar, it quickly removes sugar from your blood, which may lead to a sudden drop in blood sugar levels, a condition known as hypoglycemia (10Trusted Source, 11Trusted Source).
Low blood sugar levels signal your body that it needs more food, which is another reason why you may feel hungry often if refined carbs are a regular part of your diet (10Trusted Source).
To reduce your refined carb intake, simply replace them with healthier, whole foods like vegetables, fruit, legumes, and whole grains. These foods are still high in carbs, but they are rich in fiber, which helps keep hunger under control (12Trusted Source).
Refined carbs lack fiber and cause blood sugar fluctuations, which are the primary reasons why eating too many of them may leave you feeling hungry.
4. Your Diet is Low in Fat
Fat plays a key role in keeping you full.
This is partly due to its slow gastrointestinal transit time, meaning that it takes longer for you to digest and remains in your stomach for a long period. Additionally, eating fat may lead to the release of various fullness-promoting hormones (13Trusted Source, 14, 15Trusted Source).
For these reasons, you may feel frequent hunger if your diet is low in fat.
One study including 270 adults with obesity found that those who followed a low-fat diet had significant increases in cravings for carbs and preferences for high-sugar foods, compared with a group that consumed a low-carb diet (16Trusted Source).
Furthermore, those in the low-fat group reported more feelings of hunger than the group that followed a low-carb eating pattern (16Trusted Source).
There are many healthy, high-fat foods that you can include in your diet to increase your fat intake. Certain types of fats, such as medium-chain triglycerides (MCTs) and omega-3 fatty acids, have been studied the most for their ability to reduce appetite (17Trusted Source, 18Trusted Source, 19Trusted Source, 20Trusted Source).
The richest food source of MCT is coconut oil, while omega-3 fatty acids are found in fatty fish like salmon, tuna, and mackerel. You can also get omega-3s from plant-based foods, such as walnuts and flaxseeds.
Other sources of healthy, high-fat foods include avocados, olive oil, eggs, and full-fat yogurt.
You may feel hungry often if you don't eat enough fat. That's because fat plays a role in slowing digestion and increasing the production of fullness-promoting hormones.
5. You’re Not Drinking Enough Water
Proper hydration is incredibly important for your overall health.
Drinking enough water has several health benefits, including promoting brain and heart health and optimizing exercise performance. Additionally, water keeps your skin and digestive system healthy (21Trusted Source).
In one study, 14 people who drank 2 cups of water before a meal ate almost 600 fewer calories than those who didn't drink any water (24Trusted Source).
Due to water's role in keeping you full, you may find that you feel hungry frequently if you're not drinking enough of it.
Feelings of thirst can be mistaken for feelings of hunger. If you're always hungry, it may help to drink a glass or two of water to find out if you are just thirsty (23Trusted Source).
To ensure you're properly hydrated, simply drink water when you feel thirsty. Eating lots of water-rich foods, including fruits and vegetables, will also contribute to your hydration needs (25Trusted Source).
You may always be hungry if you're not drinking enough water. That's because it has appetite-reducing properties. Additionally, you may be mistaking feelings of thirst for feelings of hunger.
6. Your Diet Lacks Fiber
If your diet lacks fiber, you may feel hungry frequently.
Additionally, a high fiber intake influences the release of appetite-reducing hormones and the production of short-chain fatty acids, which have been shown to have fullness-promoting effects (12Trusted Source).
It's important to note that there are different types of fiber, and some are better than others at keeping you full and preventing hunger. Several studies have found soluble fiber, or fiber that dissolves in water, is more filling than insoluble fiber (27Trusted Source, 28Trusted Source, 29).
Many different foods, such as oatmeal, flax seeds, sweet potatoes, oranges, and Brussels sprouts, are excellent sources of soluble fiber.
Not only does a high-fiber diet help reduce hunger, but it's also associated with several other health benefits, such as a reduced risk of heart disease, diabetes, and obesity (30Trusted Source).
To ensure you're getting enough fiber, opt for a diet that's rich in whole, plant-based foods, such as fruits, vegetables, nuts, seeds, legumes, and whole grains.
If your diet lacks fiber, you may find that you are always hungry. This is because fiber plays a role in reducing your appetite and keeping you full.
7. You Eat While You’re Distracted
If you live a busy lifestyle, you may often eat while you are distracted.
Although it may save you time, distracted eating can be detrimental to your health. It's associated with greater appetite, increased calorie intake, and weight gain (31Trusted Source).
The primary reason for this is because distracted eating reduces your awareness of how much you're consuming. It prevents you from recognizing your body's fullness signals as efficiently as when you're not distracted (31Trusted Source).
Several studies have shown that those who engage in distracted eating are hungrier than those who avoid distractions during mealtimes (31Trusted Source).
In one study, 88 women were instructed to eat either while distracted or sitting in silence. Those who were distracted were less full and had a significantly greater desire to eat more throughout the day, compared with the non-distracted eaters (32Trusted Source).
Another study found that people who distracted themselves with a computer game during lunch were less full than those who did not play the game. Additionally, the distracted eaters consumed 48% more food in a test that occurred later that day (33Trusted Source).
To avoid distracted eating, you can try practicing mindfulness, minimizing screen time, and silencing your electronic devices. This will allow you to sit down and taste your food, helping you better recognize your body's fullness signals.
Distracted eating may be a reason why you are always hungry, as it makes it difficult for you to recognize feelings of fullness.
8. You Exercise a Lot
Individuals who exercise frequently burn a lot of calories.
This is especially true if you regularly participate in high-intensity exercise or engage in physical activity for long durations, such as in marathon training.
Research has shown that those who exercise vigorously on a regular basis tend to have a faster metabolism, which means that they burn more calories at rest than those who exercise moderately or live sedentary lifestyles (34Trusted Source, 35Trusted Source, 36Trusted Source).
In one study, 10 men who engaged in a vigorous 45-minute workout increased their overall metabolic rate by 37% for the day, compared with another day when they did not exercise (37Trusted Source).
Another study found that women who exercised at a high intensity every day for 16 days burned 33% more calories throughout the day than a group that did not exercise and 15% more calories than moderate exercisers. The results were similar for men (38Trusted Source).
Although several studies have shown exercise to be beneficial for suppressing appetite, there is some evidence that vigorous, long-term exercisers tend to have greater appetites than those who do not exercise (39Trusted Source, 40Trusted Source, 41Trusted Source, 42Trusted Source).
You can prevent excessive hunger from exercise simply by eating more to fuel your workouts. It is most helpful to increase your intake of filling foods that are high in fiber, protein, and healthy fats.
Another solution is to cut back on the time you spend exercising or reduce the intensity of your workouts.
It's important to note that this mostly applies to those who are avid athletes and work out frequently at a high intensity or for long periods. If you exercise moderately, you probably don't need to increase your calorie intake.
Individuals who regularly exercise at a high intensity or for long durations tend to have greater appetites and faster metabolisms. Thus, they may experience frequent hunger.
9. You’re Drinking Too Much Alcohol
Studies have shown that alcohol may inhibit hormones that reduce appetite, such as leptin, especially when it is consumed before or with meals. For this reason, you may feel hungry often if you drink too much alcohol (43Trusted Source, 44Trusted Source, 45Trusted Source).
In one study, 12 men who drank 1.5 ounces (40 ml) of alcohol before lunch ended up consuming 300 more calories at the meal than a group that drank only 0.3 ounces (10 ml) (46Trusted Source).
Additionally, those who drank more alcohol ate 10% more calories throughout the entire day, compared with the group that drank less. They were also more likely to consume high amounts of high-fat and salty foods (46Trusted Source).
Another study found that 26 people who drank one ounce (30 ml) of alcohol with a meal consumed 30% more calories, compared with a group that avoided alcohol (47Trusted Source).
Alcohol may not only make you hungrier but also impair the part of your brain that controls judgment and self-control. This may lead you to eat more, regardless of how hungry you are (44Trusted Source).
To reduce the hunger-inducing effects of alcohol, it's best to consume it moderately or avoid it completely (48Trusted Source).
Drinking too much alcohol may cause you to feel hungry frequently due to its role in decreasing the production of hormones that promote fullness.
10. You Drink Your Calories
Liquid and solid foods affect your appetite in different ways.
If you consume a lot of liquid foods, such as smoothies, meal replacement shakes, and soups, you may be hungrier more often than you would be if you ate more solid foods.
Eating liquid foods also tends to take less time than eating solid foods. This may lead you to want to eat more, only because your brain hasn't had enough time to process fullness signals (53Trusted Source).
In one study, people who consumed a liquid snack reported less fullness and more feelings of hunger than those who consumed a solid snack. They also consumed 400 more calories throughout the day than the solid-snack group (52Trusted Source).
To prevent frequent hunger, it may help to focus on incorporating more solid, whole foods into your diet.
Liquid foods do not have the same effects on keeping you full and satisfied as solid foods do. For this reason, you may feel hungry frequently if liquids are a major part of your diet.
11. You’re Overly Stressed
Excess stress is known to increase appetite.
This is mostly due to its effects on increasing levels of cortisol, a hormone that has been shown to promote hunger and food cravings. For this reason, you might find that you are always hungry if you experience frequent stress (54Trusted Source, 55Trusted Source, 56Trusted Source, 57Trusted Source).
In one study, 59 women who were exposed to stress consumed more calories throughout the day and ate significantly sweeter foods than women who were not stressed (57Trusted Source).
Another study compared the eating habits of 350 young girls. Those with higher stress levels were more likely to overeat than those with lower levels of stress. The stressed girls also reported higher intakes of unhealthy snacks like chips and cookies (58Trusted Source).
Excessive stress is a reason why you may be hungry frequently, given its ability to increase cortisol levels in the body.
12. You’re Taking Certain Medications
Several medications may increase your appetite as a side effect.
The most common appetite-inducing medications include antipsychotics, such as clozapine and olanzapine, as well as antidepressants, mood stabilizers, corticosteroids, and anti-seizure drugs (61Trusted Source, 62Trusted Source, 63Trusted Source, 64Trusted Source).
Additionally, some diabetes medications, such as insulin, insulin secretagogues, and thiazolidinediones, are known to increase your hunger and appetite (65Trusted Source).
There is also some anecdotal evidence that birth control pills have appetite-stimulating properties, but this is not supported by strong scientific research.
If you suspect that medications are the cause of your frequent hunger, it may help to talk to your healthcare provider about other treatment options. There may be alternative medications that don't make you hungry.
Certain medications cause increased appetite as a side effect. In turn, they may cause you to experience frequent hunger.
13. You Eat Too Fast
The rate at which you eat may play a role in how hungry you are.
Several studies have shown that fast eaters have greater appetites and a tendency to overeat at meals, compared with slow eaters. They are also more likely to have obesity or excess weight (66Trusted Source, 67Trusted Source, 68Trusted Source, 69Trusted Source).
In one study in 30 women, fast eaters consumed 10% more calories at a meal and reported significantly less fullness, compared with slow eaters (70Trusted Source).
Another study compared the effects of eating rates in those with diabetes. Those who ate a meal slowly became full more quickly and reported less hunger 30 minutes after the meal, compared with fast eaters (71Trusted Source).
These effects are partly due to the lack of chewing and reduced awareness that occur when you eat too fast, both of which are necessary to alleviate feelings of hunger (72Trusted Source, 73Trusted Source, 74Trusted Source).
These techniques are a part of mindful eating.
If you are hungry frequently, it may help to eat more slowly. You can do this by taking a few deep breaths before meals, putting your fork down between bites, and increasing the extent to which you chew your food.
Eating too quickly doesn't allow your body enough time to recognize fullness, which may promote excessive hunger.
14. You Have a Medical Condition
Frequent hunger may be a symptom of disease.
First, frequent hunger is a classic sign of diabetes. It occurs as a result of extremely high blood sugar levels and is typically accompanied by other symptoms, including excessive thirst, weight loss, and fatigue (76Trusted Source).
Hyperthyroidism, a condition characterized by an overactive thyroid, is also associated with increased hunger. This is because it causes excess production of thyroid hormones, which are known to promote appetite (77Trusted Source, 78Trusted Source).
Hypoglycemia, or low blood sugar levels, may also increase your hunger levels. Your blood sugar levels may fall if you haven't eaten for a while, an effect that may be exacerbated by a diet high in refined carbs and sugar (79Trusted Source).
If you suspect that you may have one of these conditions, it's important to talk with your healthcare provider to receive a proper diagnosis and discuss treatment options.
Excessive hunger is a symptom of a few specific medical conditions, which should be ruled out if you are frequently hungry.
The Bottom Line
Excessive hunger is a sign that your body needs more food.
It's often a result of imbalanced hunger hormones, which may occur for a variety of reasons, including inadequate diet and certain lifestyle habits.
You may feel hungry frequently if your diet lacks protein, fiber, or fat, all of which promote fullness and reduce appetite. Extreme hunger is also a sign of inadequate sleep and chronic stress.
Additionally, certain medications and illnesses are known to cause frequent hunger.
If you feel hungry often, it may be beneficial to assess your diet and lifestyle to determine if there are changes you can make to help you feel more full.
Your hunger could also be a sign that you are not eating enough, which can be solved by simply increasing your food intake.
In case you're eating too quickly or distracted at mealtimes, you can also practice mindful eating, which aims to minimize distractions, increase your focus, and slow your chewing to help you realize when you're full.
Reposted with permission from our media associate Healthline.
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Hanako, a female Asian elephant, lived in a tiny concrete enclosure at Japan's Inokashira Park Zoo for more than 60 years, often in chains, with no stimulation. In the wild, elephants live in herds, with close family ties. Hanako was solitary for the last decade of her life.
Hanako, an Asian elephant kept at Japan's Inokashira Park Zoo; and Kiska, an orca that lives at Marineland Canada. One image depicts Kiska's damaged teeth. Elephants in Japan (left image), Ontario Captive Animal Watch (right image), CC BY-ND
Affecting Health and Altering Behavior<p>It is easy to observe the overall health and psychological consequences of life in captivity for these animals. Many captive elephants suffer from arthritis, obesity or skin problems. Both <a href="https://doi.org/10.11609/JoTT.o2620.1826-36" target="_blank">elephants</a> and orcas often have severe dental problems. Captive orcas are plagued by <a href="https://doi.org/10.1016/j.jveb.2019.05.005" target="_blank">pneumonia, kidney disease, gastrointestinal illnesses and infections</a>.</p><p>Many animals <a href="https://doi.org/10.1016/j.neubiorev.2017.09.010" target="_blank">try to cope</a> with captivity by adopting abnormal behaviors. Some develop "<a href="https://doi.org/10.1016/j.applanim.2017.05.003" target="_blank" rel="noopener noreferrer">stereotypies</a>," which are repetitive, purposeless habits such as constantly bobbing their heads, swaying incessantly or chewing on the bars of their cages. Others, especially big cats, pace their enclosures. Elephants rub or break their tusks.</p>
Changing Brain Structure<p>Neuroscientific research indicates that living in an impoverished, stressful captive environment <a href="https://doi.org/10.1016/j.jveb.2019.05.005" target="_blank" rel="noopener noreferrer">physically damages the brain</a>. These changes have been documented in many <a href="https://doi.org/10.1002/cne.903270108" target="_blank" rel="noopener noreferrer">species</a>, including rodents, rabbits, cats and <a href="https://doi.org/10.1006/nimg.2001.0917" target="_blank" rel="noopener noreferrer">humans</a>.</p><p>Although researchers have directly studied some animal brains, most of what we know comes from observing animal behavior, analyzing stress hormone levels in the blood and applying knowledge gained from a half-century of neuroscience research. Laboratory research also suggests that mammals in a zoo or aquarium have compromised brain function.</p>
This illustration shows differences in the brain's cerebral cortex in animals held in impoverished (captive) and enriched (natural) environments. Impoverishment results in thinning of the cortex, a decreased blood supply, less support for neurons and decreased connectivity among neurons. Arnold B. Scheibel, CC BY-ND<p>Subsisting in confined, barren quarters that lack intellectual stimulation or appropriate social contact seems to <a href="https://doi.org/10.1590/S0001-37652001000200006" target="_blank" rel="noopener noreferrer">thin the cerebral cortex</a> – the part of the brain involved in voluntary movement and higher cognitive function, including memory, planning and decision-making.</p><p>There are other consequences. Capillaries shrink, depriving the brain of the oxygen-rich blood it needs to survive. Neurons become smaller, and their dendrites – the branches that form connections with other neurons – become less complex, impairing communication within the brain. As a result, the cortical neurons in captive animals <a href="https://doi.org/10.1002/cne.901230110" target="_blank">process information less efficiently</a> than those living in <a href="https://doi.org/10.1002/dev.420020208" target="_blank">enriched, more natural environments</a>.</p>
An actual cortical neuron in a wild African elephant living in its natural habitat compared with a hypothesized cortical neuron from a captive elephant. Bob Jacobs, CC BY-ND<p>Brain health is also affected by living in small quarters that <a href="https://doi.org/10.3233/BPL-160040" target="_blank">don't allow for needed exercise</a>. Physical activity increases the flow of blood to the brain, which requires large amounts of oxygen. Exercise increases the production of new connections and <a href="http://dx.doi.org/10.1126/science.aaw2622" target="_blank">enhances cognitive abilities</a>.</p><p>In their native habits these animals must move to survive, covering great distances to forage or find a mate. Elephants typically travel anywhere from <a href="https://www.elephantsforafrica.org/elephant-facts/#:%7E:text=How%20far%20do%20elephants%20walk,km%20on%20a%20daily%20basis." target="_blank">15 to 120 miles per day</a>. In a zoo, they average <a href="https://doi.org/10.1371/journal.pone.0150331" target="_blank" rel="noopener noreferrer">three miles daily</a>, often walking back and forth in small enclosures. One free orca studied in Canada swam <a href="https://doi.org/10.1007/s00300-010-0958-x" target="_blank" rel="noopener noreferrer">up to 156 miles a day</a>; meanwhile, an average orca tank is about 10,000 times smaller than its <a href="https://www.cascadiaresearch.org/projects/killer-whales/using-dtags-study-acoustics-and-behavior-southern" target="_blank" rel="noopener noreferrer">natural home range</a>.</p>
Disrupting Brain Chemistry and Killing Cells<p>Living in enclosures that restrict or prevent normal behavior creates chronic frustration and boredom. In the wild, an animal's stress-response system helps it escape from danger. But captivity traps animals with <a href="https://doi.org/10.1073/pnas.1215502109" target="_blank">almost no control</a> over their environment.</p><p>These situations foster <a href="https://doi.org/10.1037/rev0000033" target="_blank">learned helplessness</a>, negatively impacting the <a href="https://doi.org/10.1155/2016/6391686" target="_blank" rel="noopener noreferrer">hippocampus</a>, which handles memory functions, and the <a href="https://doi.org/10.1016/j.neuropharm.2011.02.024" target="_blank" rel="noopener noreferrer">amygdala</a>, which processes emotions. Prolonged stress <a href="https://doi.org/10.3109/10253899609001092" target="_blank" rel="noopener noreferrer">elevates stress hormones</a> and <a href="https://doi.org/10.1523/JNEUROSCI.10-09-02897.1990" target="_blank" rel="noopener noreferrer">damages or even kills neurons</a> in both brain regions. It also disrupts the <a href="https://doi.org/10.1016/j.neubiorev.2005.03.021" target="_blank" rel="noopener noreferrer">delicate balance of serotonin</a>, a neurotransmitter that stabilizes mood, among other functions.</p><p>In humans, <a href="https://doi.org/10.1006/nimg.2001.0917" target="_blank" rel="noopener noreferrer">deprivation</a> can trigger <a href="https://doi.org/10.3389/fnins.2018.00367" target="_blank" rel="noopener noreferrer">psychiatric issues</a>, including depression, anxiety, <a href="https://doi.org/10.3389/fnins.2018.00367" target="_blank" rel="noopener noreferrer">mood disorders</a> or <a href="https://doi.org/10.1177/1073858409333072" target="_blank" rel="noopener noreferrer">post-traumatic stress disorder</a>. <a href="https://doi.org/10.1007/s00429-010-0288-3" target="_blank" rel="noopener noreferrer">Elephants</a>, <a href="https://doi.org/10.1371/journal.pbio.0050139" target="_blank" rel="noopener noreferrer">orcas</a> and other animals with large brains are likely to react in similar ways to life in a severely stressful environment.</p>
Damaged Wiring<p>Captivity can damage the brain's complex circuitry, including the basal ganglia. This group of neurons communicates with the cerebral cortex along two networks: a direct pathway that enhances movement and behavior, and an indirect pathway that inhibits them.</p><p>The repetitive, <a href="http://dx.doi.org/10.1016/j.bbr.2014.05.057" target="_blank">stereotypic behaviors</a> that many animals adopt in captivity are caused by an imbalance of two neurotransmitters, dopamine and <a href="https://doi.org/10.1016/j.neubiorev.2010.02.004" target="_blank" rel="noopener noreferrer">serotonin</a>. This impairs the indirect pathway's ability to modulate movement, a condition documented in species from chickens, cows, sheep and horses to primates and big cats.</p>
The cerebral cortex, hippocampus and amygdala are physically altered by captivity, along with brain circuitry that involves the basal ganglia. Bob Jacobs, CC BY-ND<p>Evolution has constructed animal brains to be exquisitely responsive to their environment. Those reactions can affect neural function by <a href="https://www.penguinrandomhouse.com/books/311787/behave-by-robert-m-sapolsky/" target="_blank">turning different genes on or off</a>. Living in inappropriate or abusive circumstance alters biochemical processes: It disrupts the synthesis of proteins that build connections between brain cells and the neurotransmitters that facilitate communication among them.</p><p>There is strong evidence that <a href="https://doi.org/10.1523/JNEUROSCI.0577-11.2011" target="_blank">enrichment</a>, social contact and appropriate space in more natural habitats are <a href="https://doi.org/10.1111/j.1748-1090.2003.tb02071.x" target="_blank" rel="noopener noreferrer">necessary</a> for long-lived animals with large brains such as <a href="https://doi.org/10.1371/journal.pone.0152490" target="_blank" rel="noopener noreferrer">elephants</a> and <a href="https://doi.org/10.1080/13880292.2017.1309858" target="_blank" rel="noopener noreferrer">cetaceans</a>. Better conditions <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5543669/" target="_blank" rel="noopener noreferrer">reduce disturbing sterotypical behaviors</a>, improve connections in the brain, and <a href="https://doi.org/10.1038/cdd.2009.193" target="_blank" rel="noopener noreferrer">trigger neurochemical changes</a> that enhance learning and memory.</p>