8 Scary Things That Could Happen to Your Body When You Skip Meals

Whether you're joining in on the intermittent fasting craze, working through lunch or skipping breakfast, going too long between meals can have some serious consequences. Food helps to power every system in our bodies, so pretty much every part of your body is impacted when you skip a meal or fast.

We asked Christy Harrison, M.P.H., RD, CDN, author of Anti-Diet and host of the Food Psych podcast, as well as Jessica Ball, M.S., RD, EatingWell's associate nutrition editor, about the potential consequences that skipping a meal may have.

"While proponents of fasting love to tout the science that supposedly supports skipping meals, that science is very preliminary and is in no way sound enough to support recommending fasting, given all of the risks," warns Harrison. "In my view, there are no potential benefits to fasting or skipping meals, and there are very real dangers."

Here are a few of those dangers that can be brought on by skipping meals.

Anxiety

Skipping a meal—or going too long without eating in general—could have a serious impact on your mental health. A 2018 study published in the International Journal of Environmental Research and Public Health found that adolescents who skipped breakfast were more likely to experience stress and depression than those who regularly ate breakfast.

When you go too long without eating, your blood sugar takes a dip, signaling your body to start producing cortisol, according to the Endocrine Society. Cortisol, commonly referred to as the "stress hormone," is released to try to help regulate that dip in blood sugar, but it's also creating a stress response in the body. This can not only leave you feeling anxious or depressed but also moody, irritable and frazzled.

Low Energy

These huge swings in blood sugar aren't doing any favors for your energy levels. Just think of how awful you feel when you're "hangry!" Plus, according to the 2021 book, Recent Developments in Applied Microbiology and Biochemistry, our brains literally run on glucose, which they prefer to get from our consumption of carbohydrates.

Not only does skipping a meal mean less fuel for your brain, but also fewer calories for your body to run on, leaving you dragging. And you certainly shouldn't aim to burn calories through exercise if you've skipped out on a meal, as it just leaves even fewer for your brain to use up. Speaking of which, this is yet another reason to avoid the keto diet, as it leaves very little glucose for your brain and body to use.

Mixed Up Hunger and Fullness Cues

Our bodies have built-in hunger and fullness cues in the form of hormones. Simply put, leptin is the hormone responsible for decreasing your appetite when your body has had enough food, and ghrelin makes you hungry when your body needs more fuel. These hormones can be easily thrown off when you don't listen to them—even for the sake of eating within a certain window.

"Your body's hunger and fullness cues are a great indicator of when you need nourishment," says Ball. "Overlooking these to follow an externally-focused eating schedule can lead to losing touch with these cues in a major way over time. Losing a grasp on what hungry and full feel like for you can lead to negative health consequences—and they can be difficult to regain."

Food Cravings

One of the consequences of having low blood sugar and disregarding your hunger and fullness cues could be some serious cravings—specifically for simple carbs and sugar. Both of these give you quick, short bursts of energy, which is what your body is willing to settle for at this point because it's simply looking for some form of energy—anything that will give it what it needs right now.

Harrison says two research-backed consequences of skipping meals are persistent, intrusive thoughts of food as well as a loss of control over eating your next meal or snack—particularly when it comes to these refined carbohydrate sources. This means your efforts to lose weight by skipping meals or ignoring your hunger cues to eat within a specific window could actually backfire and lead to binge eating.

Skipping meals can quickly turn to self-sabotage, and your jeans could actually end up feeling tighter. In fact, according to a 2022 review in Nutrients, there are plenty of studies out there that associate skipping meals—breakfast in particular—and eating irregularly with several negative health consequences, including an increased risk of obesity and metabolic syndrome.

According to the National Heart, Lung, and Blood Institute, metabolic syndrome is an umbrella term for a collection of negative health measures, including high blood pressure, high blood triglycerides, high fasting blood glucose, higher waist circumference and low HDL ("good") cholesterol. This, in turn, can lead to other chronic diseases, such as heart disease and diabetes.

Nutrient Deficiencies

Skipping meals can lead to nutritional deficiencies for several reasons. First, skipping a meal also means you're skipping out on the opportunity to nourish your body with the dozens of essential nutrients it needs to thrive, according to a 2021 study in Proceedings of the Nutrition Society.

Additionally, giving in to those refined-carb cravings after going too long without eating fills you up for a moment, but these foods lack the substance needed to nourish your body on a deeper level. While carbs are an essential part of the human diet, we should prioritize eating carbs such as whole grains, fruit, legumes and dairy over things like cookies and white bread, which should be eaten in moderation.

Irregular Digestion

Harrison says skipping meals could lead to both nausea and diarrhea, and you could even become constipated. According to the American Psychological Society, similar to when you're feeling anxious, the stress response released by the body when going too long between meals can irk the digestive system and make your bathroom trips unpredictable. And if you're in a vicious cycle of skipping a meal and then binge eating, this will further thwart your digestion.

Your body knows exactly how much it can handle, and listening to those hunger and fullness cues—along with eating fiber-rich plant foods—will help you regain proper digestive habits.

Increased Risk of an Eating Disorder

"People who fast or skip meals are at higher risk of developing an eating disorder," says Harrison. "All of these consequences are harmful to people's overall wellbeing, and at a deeper level, they keep us from being fully present in our lives, from living our purpose and from harnessing our power to change the world."

According to a 2022 study in the journal Eating and Weight Disorders, dieting and skipping meals are strongly correlated with developing an eating disorder. Skipping a meal in order to consume fewer calories, whether out of guilt for something you ate earlier or because the food around you isn't "healthy enough," isn't just unhealthy for your brain, but also for your mindset and body. And ultimately, this could become life-threatening.

Decreased Enjoyment of Food

Enjoyment is an important part of eating—we have taste buds for a reason, right?

"Eating on a really strict schedule may not work that well for your current routine and doesn't provide much wiggle room for when things don't go according to plan," says Ball. "If you make eating more like a chore, it can be less enjoyable and more like a task to complete. Food is a necessity, but it should also be pleasurable as well as nourishing."

Two practices that have been shown to have real, research-backed benefits for health and weight management are mindful eating and intuitive eating. Mindful eating encourages using all of your senses to enjoy your food. Instead of eating your lunch at your desk while in the middle of a project, set aside distractions and simply focus on enjoying the food you're eating and the nourishment it's providing.

Mindful eating is one aspect of intuitive eating, which takes an even more personal approach, encouraging you to ditch the diet mentality and instead trust your body to be your guide. Intuitive eating encompasses listening to one's hunger and fullness cues, not restricting foods or food groups, enjoying eating and figuring out which foods work best with your body based on food preferences and how the food makes you feel (like how it affects your energy and digestion).

Bottom Line

Your body works best when it gets the nourishment it requires. This includes regularly feeding it what it needs to keep your energy levels up and your brain clear and focused. Skipping meals has been linked with several negative health consequences, including certain diseases, poor health measurements, eating disorders, low energy and anxiety. If you're in the habit of skipping meals, work on getting into a healthier routine and get to know your body's hunger and fullness cues.