“I don’t know what’s going on with me. I’m sluggish all day at work, I keep zoning out, and I’m having so much trouble getting anything done.”

“Are you doing anything different?”

“No, not that I can think of. The only thing that’s new is since I’ve been working longer hours, I’ve had less time to cook, so I’ve been eating out a lot. But that can’t be it.”

My friend Jackie was at a complete loss for why she was struggling at work, but once she told me about her new dietary habits, it clicked.

Sometimes when work starts to feel impossible, it’s easy to blame ourselves and think we just have to buckle down and work harder. But like Jackie, you might not realize that what you eat can have a significant impact on your productivity.

There are a few reasons our diet affects your work day. Undereating can make you cranky, or “hangry,” which can lead to you snapping at your coworkers or resenting your projects, putting a serious damper on your productivity. Low blood sugar can cause exhaustion, making it more difficult to complete tasks.

It follows that the benefits of healthy eating for productivity are many, and hugely important for maintaining a happy and balanced day.

Here’s some benefits that healthy eating has, that will help boost your productivity and make the work day a breeze.

Better sleep
You might think that sleep and food have nothing to do with each other, but it’s actually the opposite. Our internal clock is, in fact, greatly affected by our diet. A Cambridge University study found that a lack of nutrients during the day were directly linked to poor sleep, and another study concluded that those who ate more sugar in their diet had more trouble staying asleep at night. Basically, their sleep was more restless, causing them to be more tired the next day.

Unfortunately, it can become a vicious cycle. The more tired you are, the less likely you are to spend the time making healthy food, and it goes on, and on, and on. A great way to start breaking the cycle is making sure you have a nutritious breakfast to kickstart a healthy day, and staying away from sugars late at night (if you’re feeling snacky at midnight, try a handful of nuts or some cottage cheese. They’re full of tryptophan, which the body converts into serotonin, which in turn makes us sleepy).

More energy
Have you ever felt sleepy after lunch? You know, the 2 PM slump, the midday crash? When you’re on a deadline and rushing through your lunch break, a quick bite from a fast food joint might sound appealing, and even efficient. But what you put in your body has a direct impact on your performance. Think about the last time you struggled in the middle of your work day — do you remember what you ate for lunch? Chances are, it was high in carbs and sugar.

Remember tryptophan, that nice little acid that makes us happy and sleepy? Well, it doesn’t just work at night. Carbohydrates help absorb more tryptophan, meaning that foods high in carbs tend to make us sleepier. Sugary and starchy foods also release more serotonin, flooding us with those happy, sleepy vibes. So next time you’re craving a burger and fries for lunch, opt for something a little lighter, like a wrap or sushi. You’ll have more energy during the day to get your work done efficiently.

Better decision making
Now, stay with me here — yes, a more nutritious diet can actually help you make better decisions, which will help you stay on track and be more productive.

You might know that low blood sugar can make you feel tired and worn out. But did you also know that it directly affects self-control? Studies show that blood sugar, or glucose, is responsible for most, if not all, of the activity in the brain. Since decision making and self-control are intricate brain functions, they require appropriate levels of glucose in order to operate properly.

Basically, low blood sugar doesn’t just slow down your body; it also slows down your brain, and makes it harder to make good decisions. This might look like choosing to scroll Instagram for a few extra minutes instead of answering that email right away, or staying late on your lunch break. A few ways to make sure your blood sugar levels are right are to eat consistently throughout the day, avoid large meals, and make sure you have breakfast.

I let Jackie know that it was probably her diet that was squashing her productivity. At first, she found it hard to believe that such a small change could affect her so much at work. But I explained to her that her diet isn’t a small thing at all. It’s hugely responsible for the way our bodies and brains function, and therefore massively important to productivity.

She left our conversation lighter, and more determined to eat better and get herself on the right track. If you’re finding yourself struggling, try taking a step back and seeing if your diet can use any changing. Think about food as fuel — you only get out what you put in. With a little effort, you can start running as efficiently as possible!