Fresh fruits promote body well-being principally. Fruits are heat-energy-giving mainly according to the sugar natural in them or added to them. The acids and pectin in foods add some heat-energy. Fruits differ most in sugar and water present. Dried and preserved fruits are less wholesome than fresh, ripe fruit.

The slight variation in the quantities of the other constituents little reveals the many individual distinctions among fruits. Though these small-amount constituents are the ones that distinguish fruits from other foods and act much the same in all fruits, they are not all equally favorable for all individuals. Oranges, apples, strawberries may signally fail to agree with individuals. No class of foods shows this individual difference more markedly than fruits. Change in food-combination may make an unacceptable food digest. Change of season or climate may. But if a food persistently does not, it should be avoided. What does not digest does not nourish, and becomes a harmful agency in the working of the body.

Ripe fruits, fresh and well washed as eaten, are free from the dangers of unripe, dust-laden, or decaying fruit. Raw starch, excess of acids, and cellulose make unripe fruit unsafe food. Fruits eaten between meals and at the beginning (when not exceedingly acid) are laxative, so aid the body to keep free from waste products; as do also green vegetables.

Laxative fruits are apples, dates, figs, prunes, peaches (ripe), berries, orange- and grape-juice. (Berries are inadvisable for young children. All fruits for children should be skinned and seeded).

Uncooked fruits are somewhat more laxative than cooked.