A single cup of cubed, raw butternut squash contains approximately 82 calories, with 2 of those calories coming from fat. The serving also contains 22 grams of carbohydrates and 2 grams of protein.
A single serving of butternut squash contains about 457 percent of the daily recommended vitamin A. The high amount of vitamin A in butternut squash helps promote skin and mucusa integrity as well as maintaining good eyesight. It also contains 52 percent of vitamin C, 8 percent calcium and 7 percent iron. The seeds of butternut squash contain dietary fiber, which is good for digestion, and mono-unsaturated fatty acids, which are good for heart health.