Maybe you got sucked into an endless to-do list (or particularly enthralling Netflix series).

Or you may have jumped on the buzzyintermittent fasting(IF) bandwagon and foregonebreakfaston purpose.

Whatever the reason, before you know it, its somehow been six hours since youve eaten.

Alarm clock with fork and knives as hands of clock what happens when you don’t eat

Getty images/ TanyaJoy

What actually happens when you skip a meal?

Generally speaking, for most people, skipping meals can absolutely have significant effects on your brain and body.

But the scienceispretty clear on how skipping a meal is likely to make you feel in the short term.

Heres what happens when you skip meals, and why most R.D.s would generally advise against it.

First, your blood sugar and energy levels may drop.

And when you go about your day without food in your system, youre basically running on empty.

But your body will react to the dearth of fuel in various ways.

The primary one youll notice is low blood sugar.

When you skip a meal, your body starts to run low on its immediate glucose supply.

Low blood sugar can zap your energy, making you feel sluggish and weak, Zeitlin says.

Otherlow blood sugar symptomscan include shakiness, sweatiness, and irritability.

Soon, your growling stomach becomes all-consuming.

It can be hard to think about anythingbutfood when your brain and body are starved for energy.

Skipping meals can also make healthy choices harder.

That will probably make you feel better quickly.

The problem is that the boost can be temporary if you load up on carbs alone.

Youre also liable to be hungry again soon.

That can cause nausea, constipation,bloating, and exhaustion.

Then theres physical activity.

Some people preferworking out on an empty stomach, which is usually just fine.

But many people will do best with at least a light snack.

It can be difficult to rev yourself up for a workout when youre low-energy and food-focused.

If youre interested in trying IF, talk to a doctor or R.D.

who can help you decide if thats a smart eating plan for you.