How you eat can have a major impact on your energy throughout the day, and even impact how well you sleep. The common advice is to get enough protein, avoid eating between meals, and be sure to have your last meal of the day four hours before bedtime. It all seems reasonable—that is, until you’re lying in bed with a growling tummy and a mind that won’t stop obsessing.

Turns out that having an afternoon snack can make all the difference—provided that the snack in question contains the right nutrients, of course. In fact, according to the principles of chrononutrition, which involves eating according to the body’s biological needs at a given moment, eating certain nutrients in the afternoon can drastically your nighttime snooze.

Why have a snack?

In the late afternoon, the body’s blood sugar levels naturally dip. As an added bonus, serotonin, the hormone that promotes feelings of wellbeing and regulates sleep-wake rhythms, is synthesized into melatonin when the sun begins to set, thanks to the amino acid tryptophan. Both of these factors can influence our appetite, which is why we often crave a snack as soon as the work day begins to end.

In other words, craving an afternoon snack is perfectly natural. But choosing what to eat when the craving hits is key. The goal is to provide the body with energy without causing blood sugar to spike—and, to eat something healthy that will provide sustenance without ruining our appetite for dinner.

The importance of magnesium and tryptophan

For a restful night’s sleep, “it’s best to target foods rich in sleep-inducing nutrients such as magnesium and tryptophan,” explains Dr Laure Hyvernat, a gut microbiota expert.

Increasing magnesium intake through diet or supplements, has been shown to significantly improve sleep quality. Magnesium also has a powerful calming effect. Avocados, dark chocolate (90% raw cacao), and walnuts are excellent sources of this precious mineral. Most of us suffer from magnesium deficiency due to high levels of stress and poor digestion, which adds up to poor absorption of nutrients.

Tryptophan is an essential amino acid and precursor of melatonin, the sleep hormone. Eating tryptophan-rich foods will facilitate the synthesis of melatonin and have a positive impact on your nights. It is also the precursor of the neurotransmitter serotonin, also known as the happiness hormone. Tryptophan is found in large quantities in bananas, almonds, and chocolate, or more precisely in cacao, so choose a version with at least 90% cocoa.

Afternoon snacks that improve sleep

Banana

“Rich in tryptophan, magnesium, B vitamins, and carbohydrates, the banana is the ideal fruit to have at snack time. As an added bonus, it’s rich in prebiotic fiber, which nourishes your microbiota and thus contributes to a strong immune system during germ season,” says Hyvernat.

Dark chocolate

Chocolate with a high cocoa content makes a great snack thanks to “its rich magnesium content, which helps you cope with everyday stress,” notes Hyvernat. Just one caveat about chocolate: It can be energizing because it contains caffeine and theobromine, so avoid eating it too close to bedtime.

Almonds

“One handful of almonds boosts tryptophan,” says Hyvernat, who recommends “activating” them by soaking them for an hour or so in a glass of water, then draining and drying them before eating. “This step not only makes them crunchier, but also deactivates their phytic acid, an anti-nutrient that prevents the proper absorption of the minerals such as iron, zinc, and calcium.”

3 recipes for healthy afternoon snacks

Bananas, almonds, and chocolate can be eaten alone, or used as ingredients to make tasty, sleep-improving afternoon snacks. Below are a few healthy options that Hyvernat recommends: