This article focuses on the practices and conceptions of prevention in home care that were prevalent among Quebec families during the first half of the 20th century. The analysis is based on an examination of 585 recipes in which prevention was an objective. The analysis finds that there are three prevention purposes in home care: strengthening, which includes caregiving acts that maintain good health and fortify the whole or particular parts of the body; cleansing and purifying, which include any care aimed at eliminating accumulated substances from the body; and finally, warding off illness. The discussion insists on the holistic nature of these practices and on their relationship to women's work.