Your stomach’s growling, your mouth is salivating, and your eyes are darting in the direction of the kitchen. This wouldn’t be strange if it were coming up to dinner time or you were waiting on the cookies you’d just baked to cool. But often, hunger can strike when you’ve already eaten — or worse, late at night when you’re trying to sleep.
If you feel like you’re always hungry, no matter how much you eat, it can be hard to maintain a healthy diet, concentrate at work, or fall asleep at night when your grumbling stomach demands attention.
Below, we’ll dive into why you might be feeling hungry all the time. And, more importantly, how you can use the RISE app to fix two key causes of constant hunger: high sleep debt and being out of sync with your circadian rhythm.
Hunger is your body telling you it needs (or wants — more on this later) food. You’ll probably recognize the familiar growls from your stomach. Ignore them for too long and you might get low energy, poor mood (or “hanger”), brain fog, headaches, and shakiness to go with it.
Hunger is normal. When your stomach is empty, it contracts and causes those familiar hunger pangs. When your blood sugar drops, so will your mood and energy levels.
When your body needs food, it releases a hormone called ghrelin, also known as the hunger hormone. You’ll get those familiar feelings of hunger and an urge to eat. If you do eat, your body will produce a hormone called leptin when it’s satisfied, causing you to feel full and stop eating. This careful balance between hunger and fullness fluctuates throughout the day.
It sounds simple enough, but hunger doesn’t always happen when we need food. Here are the different types of hunger to look out for:
Of course, you’re going to feel hungry when your body needs fuel. But hunger can be triggered by a lot more than that. Here’s why you might be feeling hungry all the time.
Sleep debt is the amount of sleep you owe your body. It’s measured against your sleep need, the genetically determined amount of sleep you need each night. When you’ve got high sleep debt, you’re going to feel tired, of course, but you might feel more hunger than usual, too.
When you don’t get enough sleep, ghrelin levels (the hunger hormone) are higher and leptin levels (the satiety hormone) are lower, a recipe for increased hunger. Research shows increased ghrelin can also lead to increased food cravings.
A lack of sleep can also impact your production of glucagon-like peptide-1 (GLP-1). GLP-1 is released after a meal to help keep your blood sugar levels under control and promote satiety. That’s why weight loss drugs that are GLP-1 receptor agonists, like Ozempic, make you feel fuller. Research shows not getting enough sleep can lead to lower levels of GLP-1. Sleep disturbances, like sleep apnea, can also impact GLP-1.
It doesn’t take much sleep loss for your hunger to be impacted. A 2019 study cut participants' time in bed by 33% for just one night. This led to increased hunger, increased food cravings, eating more chocolate, and eating larger portion sizes the next day.
And more research shows people eat 385 more calories after a night of sleep deprivation. This is just one way sleep loss can lead to weight gain and obesity.
RISE users on iOS 1.202 and above can click here to view their sleep need and here to view their sleep debt.
Your circadian rhythm is your body’s roughly 24-hour internal clock. Among other jobs, it dictates your sleep-wake cycle. When you’re out of sync with your circadian rhythm — which can happen when you sleep and eat at odd times — your hunger hormones are impacted.
One study looked at shift workers who ate and slept 12 hours out of sync. This led to a 17% increase in ghrelin levels compared to when they were in sync with their circadian rhythms. Consistently, when out of sync, they also had a 38% higher desire to eat.
A 2019 study found circadian misalignment also led to an increased appetite for energy-dense foods. And a 2022 paper states circadian misalignment reduces levels of leptin and peptide YY, another hormone in the body that helps us feel full.
RISE users on iOS 1.202 and above can click here to see their circadian rhythm on the Energy screen.
Macronutrients are carbohydrates, protein, and fat. These make up the three main nutrients we need for fuel. If you’re not getting the balance right between these macronutrients, you may be left feeling hungry, especially in between meals.
For example, a meal high in carbs will cause your blood sugar to spike and then crash, leading to hunger. A diet low in healthy fats can leave you craving sugar.
Not all macronutrients are equal, either. One study found a low-fat diet can lead to more hunger than a low-carb diet. And another study found a high-protein low-calorie diet helped people feel fuller throughout the day compared to those on a normal protein low-calorie diet. Those eating more protein also had less desire to eat late at night and were less preoccupied with thoughts of food.
Refined carbs lack nutrients and fiber, which gives you a feeling of fullness. They also spike your blood sugar, leading to hunger when you get the inevitable sugar crash.
Refined carbs include:
If you’re trying to lose weight and have cut your calories, you may feel hungrier as your body is used to more food. Cutting your calories also messes with your hunger hormones. Your body produces less leptin, meaning you don’t feel as full and satisfied.
Research also shows dieters trying to lose weight have significantly more food cravings than non-dieters.
Whether you’re turning to liquid meals because you’re dieting or grabbing a meal in a bottle at your desk, liquid meals can leave you feeling hungry, even though you’re consuming calories.
Liquids pass through our stomach more quickly and, as you can consume them faster than a solid meal, your body might not get the chance to tell you it's full. Calories from liquids have also been shown to have less of an effect on satiety levels.
You’ve probably felt the sudden drop in energy you get when your blood sugar levels are low. This is called hypoglycemia and it can happen when you skip or delay a meal.
But hypoglycemia can also happen a few hours after a meal when your blood sugar levels drop. And even though you’ve eaten, this drop can come with hunger pangs.
You might also get a crash in blood sugar if you eat a high-carb meal, drink alcohol, are stressed, or after working out.
Your body has a hard time telling hunger and thirst apart. So, you may not be hungry all the time, but actually thirsty.
Drinking water also helps you feel fuller. If you drink water before a meal, it can even reduce how much you eat.
One study asked participants to drink two cups of water just before eating a meal. Those who drank the water felt fuller, more satisfied, and ate less compared to those who didn’t drink anything before the meal.
According to the US National Academies of Sciences, Engineering, and Medicine, women should drink about 2.7 liters (about 11.5 cups) of water a day and men should drink 3.7 liters (about 15.5 cups) a day. You may need to drink more if you do a lot of exercise or live in a hot climate.
Time-restricted eating often involves eating all of your meals in a set window of time, say within eight hours from midday to 8 p.m. You may have also heard of intermittent fasting, which often involves a time restriction and a cut in calories. But there’s no set definition for either term.
If you’re trying time-restricted eating, even without a cut in calories, you may be hit with hunger in the first week or so as your body is used to more regular and spaced out meals. You don’t have what’s called metabolic flexibility yet, which is when your body can switch between burning glucose and fat for fuel.
You can learn more about metabolic flexibility here, including what causes inflexibility, and time-restricted eating here.
We’ve probably all been stressed and at one point turned to a sugary snack to feel better. But if you’re living in a state of chronic stress, you may be feeling chronically hungry as a result.
Research shows leptin levels decrease after a bout of stress, whereas ghrelin levels increase. Stress also hikes your cortisol levels, which can increase your appetite and food cravings.
The added danger of stress hunger is that it makes you crave unhealthy foods. Stress can trigger cravings for “hyper-palatable foods,” often junk food, or food that is very sweet, salty, or fatty.
It’s a vicious circle, too. When we eat these enjoyable foods, our brains release the chemical dopamine, making us feel happy. Your brain can then create more dopamine receptors in response to the high levels of the chemical. This means you need more dopamine (i.e. more junk food) to feel the same levels of satisfaction.
A diet of high-fat/high-sugar food may also make healthier food less palatable alongside these neurobehavioral adaptations. In a randomized controlled study from March 2023, normal weight participants had high-fat/high-sugar snacks or low-fat/low-sugar snacks for 8 weeks, alongside their regular meals. The high-fat/high-sugar intervention made people less interested in low-fat food while increasing their brain’s response to food and associative learning independent of food cues or reward. These changes happened independent of any changes in body weight or metabolism, suggesting high-fat/high-sugar foods directly impact our brains and could make us more likely to overeat and gain weight.
And sleep deprivation and circadian misalignment are forms of stress for your body. These two things can hike cortisol levels and contribute to your increased hunger.
We cover the best breathing exercises for sleep here.
Whether you’re having dinner in front of the TV or eating lunch at your desk, it’s easy to be distracted at mealtime. But this distraction can stop you from recognizing fullness signals from your body.
Research shows eating when distracted can lead to eating more in the moment and eating more food later in the day, too. And chewing for longer may even increase GLP-1 levels, which can help you feel fuller.
You might also be stressed by this distraction — if you’re eating while responding to taxing emails or grabbing breakfast while getting the kids ready for school, for example. And this stress can contribute to hunger, too.
Maybe you’re training for a marathon or hitting new PBs in the gym, either way, high levels of exercise can increase your appetite as your body burns more fuel.
You won’t just feel hungry right after a workout, though. Exercise can make you hungrier in general. One study asked participants to do resistance exercises three times per week for eight weeks. Their appetite significantly increased, whereas no changes in appetite were seen in those who didn’t do resistance training.
Working out can be good for your hunger, too, though. Research shows exercise can improve GLP-1 levels, which helps you feel full. And it can help you fall asleep at night. Just be sure to avoid intense workouts in the hour before bed, as this can keep you up.
We’ve covered more on the best time to work out here. And RISE can tell you when to avoid intense exercise each day.
RISE users on iOS 1.202 and above can click here to set up their avoid late workouts reminder.
Alcohol could be behind your hunger for a few reasons. Firstly, research suggests alcohol can reduce how much leptin you produce, which can stop you from feeling full and satisfied.
Secondly, alcohol can lower your self-control and leave you craving (and perhaps indulging in) salty, fatty, and sweet foods, and possibly overeating in general.
Thirdly, alcohol could be behind other common culprits of constant hunger, like high sleep debt.
RISE can remind you when to have your last alcoholic drink each day to stop it from impacting sleep. And we’ve covered how long before bed you should stop drinking alcohol here.
RISE users on iOS 1.202 and above can click here to set up their avoid late alcohol reminder.
An increased appetite is just one of the side effects of nicotine withdrawal. And, if you’ve just quit, you also might be feeling other stress-inducing side effects, and this stress is contributing to an increased appetite, food cravings, and sleep loss (and therefore even more hunger).
Beyond emotional eating to soothe cramps and anxiety, your menstrual cycle can impact your hunger levels in other ways. Food intake is generally higher after ovulation and before your period starts, also known as the luteal phase. You may also get more food cravings during this time, too.
One study found women with premenstrual dysphoric disorder (or PMDD, a severe form of premenstrual syndrome) had higher cravings for fatty foods and ate more calories in the luteal phase of their cycles, whereas women without PMDD didn’t.
You may also have trouble sleeping on or around your period, and the resulting sleep deprivation can make hunger worse. We’ve covered how to sleep on your period here.
Along with low energy and morning sickness, you might experience an increased appetite when pregnant as your body needs more fuel for your growing baby.
Pregnancy can also make it harder to sleep and it’s easy to feel stress and anxiety at this time, which can add to increased hunger levels.
The same goes for when you're breastfeeding. Your body is working hard to produce milk and so needs more calories to do so. And sleep loss from nighttime feeds may be making your hunger even worse.
We’ve covered how you can get energy when pregnant here.
Certain medications can increase your appetite, including:
If you’re using cannabis for pain or anxiety (or recreationally), this can increase your appetite, too.
Beyond medications, health conditions can also be contributing to hunger. These include:
How you stop your hunger will all depend on what’s causing it, of course. But two overlooked fixes include lowering your sleep debt and getting in sync with your circadian rhythm.
The win-win here? Lowering your sleep debt and getting in sync with your circadian rhythm won’t only help keep your hunger levels in check, they’ll boost your energy levels, mood, and mental and physical health, too. Here’s what to do.
Use RISE to find out your unique sleep need then aim to get as close as you can to that number each night.
RISE can keep track of your sleep debt each day. We recommend you keep this below five hours to feel and function your best, and reduce your chances of high sleep debt hijacking your hunger levels.
If you’ve got high sleep debt, you can pay it back by:
We asked our sleep advisor and medical reviewer, Dr. Chester Wu, for his top tips on getting more sleep to keep your hunger levels in check:
“Sleep deprivation can leave you feeling hungry all the time, even when you’ve eaten enough. Try getting sunlight first thing in the morning, reducing light exposure in the evenings, and doing a relaxing bedtime routine to get more sleep and, hopefully, feel less hunger.” Rise Science Medical Reviewer Chester Wu
RISE users on iOS 1.202 and above can click here to view their sleep debt.
RISE predicts your circadian rhythm each day based on factors like your inferred light exposure and last night’s sleep times. You can then see when your body naturally wants to wake up, wind down for bed, and go to sleep, making it easier to sync up your daily life to it.
Here’s how to get and stay in sync:
RISE users on iOS 1.202 and above can click here to see their circadian rhythm on the Energy screen.
There are many reasons you could be feeling hungry all the time, but two key culprits that are often overlooked are high sleep debt and circadian misalignment.
The RISE app can work out your individual sleep need and how much sleep debt you have, so you can lower it and keep it low. RISE can also predict your circadian rhythm so you can more easily live in sync with it.
The good news is lowering your debt and getting in sync with your circadian rhythm can not only help to reduce out-of-control hunger pangs, but increase your energy and overall health and well-being, too.
And if something else is causing your constant hunger — like your medication, stress, or dieting — low sleep debt and circadian alignment will help to keep cravings as low as they can be.
Two common reasons you might be feeling always hungry and tired include high sleep debt and living out of sync with your circadian rhythm. Get more sleep at night and get back in sync with your circadian rhythm to get your hunger levels in check and get more energy.
You might be always hungry as a woman when you’re in the luteal phase of your menstrual cycle, or when you’re pregnant or breastfeeding. High sleep debt, living out of sync with your circadian rhythm, poor macronutrient balance, and stress can also leave you feeling hungry all the time.
You could be always hungry even after eating because of high sleep debt, being out of sync with your circadian rhythm, not eating a good balance of macronutrients, being stressed, eating when distracted, or being dehydrated.
You might be always hungry at night because of high sleep debt, being out of sync with your circadian rhythm, not eating a good balance of macronutrients, being stressed, eating when distracted, or being dehydrated.
Being hungry all the time isn’t normal, but it’s common. You could be hungry all the time due to high sleep debt, being out of sync with your circadian rhythm, not eating a good balance of macronutrients, being stressed, eating when distracted, or being dehydrated.
Stop feeling hungry all the time by lowering your sleep debt, living in sync with your circadian rhythm, drinking enough water, keeping stress levels in check, reducing refined carbs, and eating a good mix of carbohydrates, healthy fats, and protein.
RISE makes it easy to improve your sleep and daily energy to reach your potential
RISE makes it easy to improve your sleep and daily energy to reach your potential
