20 foods that are basically calorie-free

A heaping cup of leafy, green arugula (also known as rocket) clocks in at just 5 calories. Arugula is also a solid source of vitamin K, fiber, and antioxidants. In fact, it supplies 100% of your daily recommended dosage of vitamin K, which is good for bone health.

We love grilling asparagus, which needs only olive oil (healthy!) and parmesan cheese to turn it into a savory-yet-slimming side. A half-cup serving is only 20 calories, but also contains 2 grams of fiber, 2 grams of protein, and half the daily requirement of vitamin K.

Most bell peppers—green, yellow, red, orange—are considered sweet, but that’s not reflected in the calories. A medium-sized bell pepper, or a one-cup serving, has only about 30 calories. Surprisingly, these sweet peppers are also packed with vitamin C, with well over 100% of your recommended daily value in just one pepper.

Packed with fiber, vitamin C, vitamin K, and numerous antioxidants, broccoli is also low in calories. A cup of chopped broccoli contains only 31 calories, so include it on your plate or add it in recipes as often as possible.

Cabbage is an easy way to add some substance to your meal without adding too many calories. One cup of cabbage—whether it’s for salads, sandwiches, sides (like coleslaw), or sauteed as its own dish—contains about 18 calories. Chinese cabbage, also known as bok choy, is even healthier, registering just 9 calories for the same serving size.

It’s no secret why cauliflower has recently replaced things like rice, pizza crust, and buffalo wings—it’s a much healthier option. Not only is cauliflower filled with fiber and antioxidants, but it contains just 27 calories per cup.

When a food is 95% water, it’s a solid sign there aren’t many calories involved. Such is the case with celery, which has only about 15 calories per cup. However, it also boasts nearly 15 different antioxidants, and that’s a big benefit compared to water.

Chard, or Swiss chard, is a leafy green that’s similar to spinach but is actually a member of the beet family. It contains only 35 calories in a cup—and that’s a cup of chopped chard—so don’t be shy when adding some to your next salad, soup, or stir fry.

If the bell pepper entry had you wondering about chili peppers, you’ll be delighted to know they are also very low in calories. In fact, because chili peppers are even less sweet (and spicier!), they have even fewer calories. Jalapenos, for example, have about 13 calories in a half-cup serving, while serrano peppers have about 14 calories in the same serving size.

All those recipes where cucumbers are used in place of tortilla chips, crackers, or other foods is for good reason—a cup of cucumber clocks in at just 16 calories. It also contains vitamins K, C, and B, so be sure to slice some up the next time you’re eating (or serving) a salad or dip.

Although it looks like an onion, fennel is botanically in the carrot family but tastes like anise or black licorice. If that jives with you, you’re in luck, as every cup of sliced fennel has only 27 calories! If you’ve never had fennel before, try roasting some with olive oil and parmesan. 

Some folks still swear by the century-old “grapefruit diet”—a low-sugar, low-carb, low-calorie, and high-protein diet that includes eating grapefruit or drinking grapefruit juice with every meal. It makes sense, as grapefruits are low in calories (37 per half-fruit) but filling due to their high water content, and are a solid source of vitamins, minerals, antioxidants, and fiber.

Kale packs a slightly more plentiful portion of calories compared to other leafy greens, with a one-cup serving of chopped kale containing about 33 calories. It’s worth it though, as kale is a bonafide superfood that delivers more than 100% of your recommended daily value of vitamins K, A, and C, as well as some manganese and numerous antioxidants. 

An entire cup of lettuce—bet it iceberg, bibb, red leaf, romaine, etc.—contains fewer than 10 calories. They’re mostly water, which explains the lack of calories, and also the reason why lettuce has hydrating qualities.

Sometimes you need a low-calorie snack that’s not just plain ol’ veggies. When you do, reach for a handful of popcorn. A one-cup serving of this fluffy treat contains just 31 calories. Even when popped with oil, a cup is still only 35 calories. In addition to tasting great and being filling, popcorn is also a whole grain that’s high in fiber and contains phenolic acid, an antioxidant that may have anti-inflammatory properties and other health benefits.

Radishes, a root vegetable, can keep you looking ravishing—or at least help you look healthy. A one-cup serving clocks in at just 18 calories while boasting numerous vitamins, minerals, and antioxidants.

Spinach is great for salads, sandwiches, wraps, omelets, and so much more, including your health! Of course, if you’re cooking spinach, it will shrivel up, so you’ll need to use a hefty amount. Thankfully, one cup of spinach contains only 7 calories, as well as your daily requirement of vitamins K, A, and C.

Summer squash—varieties that are harvested while still immature—have a host of health benefits in addition to low caloric content. Zucchini, for example, has 19 calories per cup, while yellow squash has 35 calories per cup. We love to barbecue both in the summer to balance out the burgers cooking on the other side of the grill.

One juicy, average-sized tomato totals just 22 calories. Or, if you’re a fan of cherry tomatoes, you can have a whole cup for that same amount of calories. Tomatoes are also rich in lycopene, an antioxidant that not only gives the fruit its color but may help prevent cancer and cardiovascular diseases.

“Watercress” is not a misnomer—this green, leafy veggie native to Europe and Asia is about 95% water and thus extremely low in calories. In fact, watercress is the lowest-calorie food in this entire list, with just 4 calories per shredded cup. This is one instance where the last really is least!