It's pretty difficult to work hard and focus if you're running around the office on fumes. You need to fuel! Lunch of course is a must. But you'll probably benefit from some light snacks, too. A little extra here and there can keep blood sugar levels stable, which wards off distracting hunger and keeps your brain humming along.

Which snacks are "best"?

Alyssa Ardolino, RD, Nutrition Communications Coordinator for the International Food Information Council, points out that you have to take personal preferences into account and find snacks that are palatable for you. You should enjoy what you're eating so it's easy to make healthy options an easy habit. She also cautions against labeling foods as "good" or "bad", since that can make you feel ashamed if you eat something that's not the greatest choice.

As a general guide, just look for snacks that

  • Are satisfying
  • Have a mix of nutrients
  • Offer convenience

"A good rule of thumb," Ardolino says, "is to try to have a mix of protein, carbs and fat in each snack."

Protein, carbohydrates and fat are the three main macronutrients your body requires to function well. All can be used for fuel at some point, but carbohydrates are most easily broken down as an immediate energy source for your brain and body. Protein and fat both help you feel full and slow digestion down. Protein is known for building and repairing muscle, but it's critical for other functions, too, such as making hormones. And while you shouldn't go overboard, fat is important for building cell exteriors and other jobs, including the absorption of vitamins and minerals. "Good" fats that help improve your cholesterol profile--the monounsaturated and polyunsaturated kinds--are found in a range of vegetables, nuts, seeds and fish.

Ardolino's recommended examples:

  • Apple with peanut butter and a hard boiled egg
  • Yogurt (ideally unsweetened or Greek) with nuts and a few whole grain crackers
  • Cucumber slices with hummus and a piece of cheese

Which snacks are "worst"?

Again, no food is necessarily "bad"--it's just that some aren't going to benefit your body as much.

"Snacks that are less satisfying could be so because they don't taste good or don't contain a good range of nutrients," Ardolino says, "[It's] helpful to aim for [healthier options] most of the time, but it's OK to eat less nutritious food at times."

So don't beat yourself up if all that's available is mini donuts. But a basic guideline here that's equally applicable to your full meals is to look for snacks with minimal processing and pronounceable, familiar ingredients. Some experts say that less than five ingredients is ideal, but that's not a hard rule (think of something like a 21-grain bread).

As detailed in WebMD, examples of snacks where you definitely could do better are

  • Potato chips
  • Snack pies
  • Movie theater microwave popcorn
  • Packaged frozen snacks, e.g., frozen pizza, breakfast sandwiches
  • Chicken nuggets

All of these foods are high in preservatives, sodium and fat without providing enough of the vitamins and minerals your body requires. Eating them too often or in excess can lead to problems such as high blood pressure, autoimmune issues or even increased cancer risk. Try replacing them with options like baked veggie chips or fries, fruit with a drizzle of honey, air-popped popcorn with spices or herbs, a homemade veggie pizza on whole grain pita and spicy baked chicken breast.

How to ensure you snack well every time

Ardolino says different factors--lack of knowledge, lack of access, high cost, inconvenience and a lack of time to prepare and shop--might be the biggest barriers to using great snacks. Eating whatever you want, she says, is a privilege many people take for granted. She recommends that you

  • Keep fruits and veggies out so they serve as visual cues.
  • Chop veggies in advance and proportion for on-the-go access. (Note: Foods break down faster when chopped, so stick to two or three days of snacks at a time to prevent spoilage.)
  • Boil eggs in batches and keep them ready to eat in the fridge.
  • Invest in reusable containers.

In addition to Ardolino's recommendations, you also might want to

  • Watch your calorie totals. Nuts can be fantastic sources of good fats, for example, but a single ounce can be as much as 200 calories.
  • Limit vending machine or cafeteria snacks to a specified number per week, or set yourself a cash allowance for the week.
  • Buy in bulk and use your own containers for portion control rather than opting for more expensive, individual snack packs.
  • Limit snacks that require refrigeration or heating to save time, ensure your munchies are always within arm's reach and prevent theft. If you have to use cold packs, remember they won't last all day, and eat the foods that rely on them first.
  • Aim for lots of color, either daily or more generally through the week. Lots of colors translate to a bigger range of nutrients and vitamins and make the snacks more visually attractive.
  • Break convention. Who says deli meat always has to go in a sandwich, for example? You'll get more snack combination options if you don't assume you "have to" do x or y.
  • Stop working when you snack. Taking the time to focus on your food makes it more enjoyable and reduces the tendency to go overboard on portion sizes.
  • Consider your office's allergen policies and how others might react to odors.
  • Plan the snacks into your agenda. Breaks are ideal for snacking because you can get up and away from your desk, but if you have to use breaks for other tasks, you still should have a guarantee you'll be able to fuel up.

You don't have to eat perfectly, and you don't even need to eat a lot. But don't buy into the myth that you can work straight through the day on air. Give yourself an edge and grab a snack you can be happy about!