Apples are rich in simple sugars like fructose, sucrose, and glucose, but their glycemic index (GI) is low, 29–44.

An apple (español: manzana) is a sweet, edible fruit produced by an apple tree (Malus domestica). Apple trees, which originated in Central Asia, are cultivated worldwide. Its wild ancestor, Malus sieversii, is still found today. There are more than 7,500 known cultivars of apples, resulting in a range of desired characteristics. Trees and fruit are prone to a number of fungal, bacterial and pest problems, which can be controlled by organic and non-organic means. In 2010, the fruit’s genome was sequenced as part of research on disease control and selective breeding in apple production.

1 raw unpeeled medium apple (100 g)
calories 82
carbohydrates 13.8 g
fat 0.2 g
fiber 2.4 g
phosphorous 11 mg (2% DV)
protein 0.3 g
vitamin B6 3 µg (3% DV)
vitamin C 4.6 mg (6% DV)
water 86%
Sources: Wikipedia