There are some people in this world who stick with three square meals a day.

For the rest of us, snacks are averyimportant part of life.

A forkful of last night’s leftovers straight out of the fridge can be a pretty fantastic late-night snack.

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Chelsea Kyle. Prop and food styling by Beatrice Chastka.

Those officecupcakesthat appeared out of the abyss can be a delicious and spontaneous snack.

Substantial, nutrient-packed snacks can be an integral part of how we fuel our bodies throughout the day.

But what does a healthy snackactuallylook like?

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Chelsea Kyle. Prop and food styling by Beatrice Chastka.

In other words, its about what fills you up and makes you feel good.

When choosing healthy snacks, think about the kinds of foods and nutrients that will help satisfy you.

Here are their recommendations.

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Its time for some complexcarbsand protein, according to the R.D.s.

They give you that boost of energy to hold you over until lunch.

Youll also want to avoid anything that can cause GI discomfort when youre working out.

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(Of course, take the intensity and length of yourworkoutinto account.

An hourlong kickboxing class typically calls for more refueling than a half-hour light yoga class.)

Here are some options:

To grab and goSometimesconveniencereally is king.

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Chelsea Kyle. Prop and food styling by Beatrice Chastka.

We dont all have time to make energy bites from scratch every single night, as Sharp puts it.

She recommends stashing shelf-stablepackaged snacksin various places, like at the office or in your bag.

For instance there are tons of great bar options out there.

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Chelsea Kyle. Prop and food styling by Beatrice Chastka.

For a fast and cost-effective homemade option, you cant beat a big batch of DIY trail mix.

Sharp suggests hitting thebulk binsto combine your favorite nuts, dried fruits, seeds, and whole grain cereals.

Dole the mix out into snack-size baggies to grab throughout the week.

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Chelsea Kyle. Prop and food styling by Beatrice Chastka.

Youre craving stimulation and youre in that munchy mood.

Thats why she especially likes in-shell nuts or seeds, which require a little bit more mindfulness for eating.

It can also be a part of that end-of-day ritual where you might just relax and kick back.

Here are some great options:

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