Wholesome, a. [Compar. Wholesomer; superl. Wholesomest.]
Etymology: [Whole + some; cf. Icel. heilsamr, G. heilsam, D. heilzaam.]
1. Tending to promote health; favoring health; salubrious; salutary. Wholesome thirst and appetite. Milton. From which the industrious poor derive an agreeable and wholesome variety of food. A Smith.
2. Contributing to the health of the mind; favorable to morals, religion, or prosperity; conducive to good; salutary; sound; as, wholesome advice; wholesome doctrines; wholesome truths; wholesome laws. A wholesome tongue is a tree of life. Prov. xv. 4. I can not . . . make you a wholesome answer; my wit's diseased. Shak. A wholesome suspicion began to be entertained. Sir W. Scott.
3. Sound; healthy. [Obs.] Shak. -- Whole"some*ly, adv. -- Whole"some*ness, n.
Shades of meaning
Fernald has no entry of its own for wholesome; he lists it under healthy.
Where he writes about it:
Wholesome food in a healthful climate makes a healthy man. — from healthy
With healthful are ranged the words hygienic, salubrious, salutary, sanitary, and wholesome, while the other words are associated with healthy. — from healthy