You might be thinking, “I’m not hungry.” But you are! And your body knows it.

Your brain sends signals to your stomach telling it that food is on its way and that it should start preparing for a meal. But if you don’t eat anything at all, those messages get ignored.

And when they do, your blood sugar drops, which can cause headaches, fatigue, irritability, dizziness, nausea, or even fainting spells.

Your blood sugar may drop.

According to Dr. David Katz, director of Yale University’s Prevention Research Center, “The first thing that will happen if you miss a meal is that your blood glucose level drops.” This means that your pancreas has less fuel to work with, so it releases more insulin — which helps bring down your blood sugar. If this continues over time, your metabolism could slow down even further.

You’ll feel tired and sluggish.

That said, some people skip meals in the form of intermittent fasting, a way of dieting in which you can eat whatever you want, but only during a specific time period.

But if you’re trying to lose weight or maintain a healthy lifestyle, skipping breakfast could be doing more harm than good. “When we don’t eat for several hours before our next meal, our bodies are forced to use stored fat as fuel instead of glucose from food,” says registered dietician Lauren Slayton. “This causes us to burn through that fat much faster — sometimes even leading to cravings for high-fat foods.” If this sounds familiar, try having an apple with nut.

You might overeat at your next meal.

If you’ve been skipping breakfast or lunch for days on end, chances are you won’t be hungry until dinner rolls around. But once hunger hits, there could be an urge to stuff yourself with unhealthy snacks instead of sticking to healthy options. “It takes about three hours after eating before fullness signals reach the brain,” explains Dr. David Zinczenko, M.D., R.D., coauthor of 8 Weeks to Optimum Health Through Healthy Living.

You won’t be in the best mood.

If you go too long without eating or drink anything other than water, you could end up feeling cranky, irritable, and downright grumpy. A study published in The Journal of Nutrition found that skipping breakfast led to increased levels of cortisol — a stress hormone associated with anxiety and depression — compared to participants who ate within an hour before bedtime.

Your body will lose its ability to endure exercise if you skip meals

If your muscles are not getting enough fuel, they cannot work as hard and efficiently during a workout. Skipping breakfast or eating only one meal can also cause fatigue because the stomach is empty for long periods of time. This causes blood sugar levels to drop which leads to low energy levels. Eating small frequent snacks throughout the day helps keep blood glucose at an even level so that it does not fluctuate like it would when you have skipped a meal.

This Is What Happens in Your Body When You’re Skipping Meals

You might be thinking, “I’m not hungry.” But you are! And your body knows it.

Your brain sends signals to your stomach telling it that food is on its way and that it should start preparing for a meal. But if you don’t eat anything at all, those messages get ignored.

And when they do, your blood sugar drops, which can cause headaches, fatigue, irritability, dizziness, nausea, or even fainting spells.

Your blood sugar may drop.

According to Dr. David Katz, director of Yale University’s Prevention Research Center, “The first thing that will happen if you miss a meal is that your blood glucose level drops.” This means that your pancreas has less fuel to work with, so it releases more insulin — which helps bring down your blood sugar. If this continues over time, your metabolism could slow down even further.

You’ll feel tired and sluggish.

That said, some people skip meals in the form of intermittent fasting, a way of dieting in which you can eat whatever you want, but only during a specific time period.

But if you’re trying to lose weight or maintain a healthy lifestyle, skipping breakfast could be doing more harm than good. “When we don’t eat for several hours before our next meal, our bodies are forced to use stored fat as fuel instead of glucose from food,” says registered dietician Lauren Slayton. “This causes us to burn through that fat much faster — sometimes even leading to cravings for high-fat foods.” If this sounds familiar, try having an apple with nut.

You might overeat at your next meal.

If you’ve been skipping breakfast or lunch for days on end, chances are you won’t be hungry until dinner rolls around. But once hunger hits, there could be an urge to stuff yourself with unhealthy snacks instead of sticking to healthy options. “It takes about three hours after eating before fullness signals reach the brain,” explains Dr. David Zinczenko, M.D., R.D., coauthor of 8 Weeks to Optimum Health Through Healthy Living.

You won’t be in the best mood.

If you go too long without eating or drink anything other than water, you could end up feeling cranky, irritable, and downright grumpy. A study published in The Journal of Nutrition found that skipping breakfast led to increased levels of cortisol — a stress hormone associated with anxiety and depression — compared to participants who ate within an hour before bedtime.

Your body will lose its ability to endure exercise if you skip meals

If your muscles are not getting enough fuel, they cannot work as hard and efficiently during a workout. Skipping breakfast or eating only one meal can also cause fatigue because the stomach is empty for long periods of time. This causes blood sugar levels to drop which leads to low energy levels. Eating small frequent snacks throughout the day helps keep blood glucose at an even level so that it does not fluctuate like it would when you have skipped a meal.