What’s in 100g blueberries?

According to USDA food data, 100g of raw blueberries contains about 57 calories, 14.5g of carbs, 2.4g of fiber, 9.7g of sugar, 0.7g of protein, and 0.3g of fat. It also provides about 84g of water, which is part of why blueberries feel refreshing and filling for their calorie count.

For micronutrients, 100g blueberries offers roughly 9.7mg vitamin C, 19.3mcg vitamin K, and 0.336mg manganese. The exact numbers can vary a little by variety and ripeness, but the overall profile stays similar: mostly carbs, very little fat, modest fiber, and a meaningful amount of antioxidants.

Health benefits of blueberries

Blueberries are known for their anthocyanins, the pigments that give them their deep blue color. These compounds are associated with antioxidant activity, and research has linked berry intake with heart-health and brain-health benefits as part of an overall healthy eating pattern.

The fiber in 100g blueberries is not huge, but it still helps support fullness and smoother digestion compared with many processed snacks. The serving is also naturally low in sodium and has no added sugar when eaten fresh or frozen plain, which makes it a strong choice for everyday fruit intake.

How 100g blueberries fits into your day

One 100g serving works well as a snack, a yogurt topping, or a mix-in for oats, smoothies, and salads. If you’re counting macros, it’s a carb-forward fruit serving, so it fits best around meals or workouts where you want quick, easy-to-digest energy.

If you track intake closely, weigh them before eating for the most accurate count. Frozen blueberries are usually nutritionally similar to fresh, but sweetened or dried blueberry products can be much higher in sugar and calories per 100g.

Things to keep in mind

Blueberries are healthy, but portion size still matters if you’re watching carbs or blood sugar. A 100g serving is reasonable for most people, yet pairing it with protein or fat, like Greek yogurt, cottage cheese, or nuts, can make the snack more satisfying.

If you’re using food photos to log meals in Fitnit, blueberries are a good example of a food where portion estimation can be tricky because a small volume can look like a lot. For workouts, Fitnit can also help with automatic rep counting and form analysis, which is useful when you want a quick, no-equipment session at home.

Tips

• Weigh 100g blueberries once so you can learn what that portion looks like in your usual bowl or hand.
• Pair blueberries with protein, like yogurt or eggs, if you want a more filling snack.
• Choose plain fresh or frozen blueberries over sweetened dried versions to keep sugar lower.
• Use blueberries in oats, smoothies, salads, or cottage cheese for easy daily fruit intake.
• If you’re meal tracking, log the fruit by weight rather than by visual estimate for better accuracy.