In mid-nineteenth-century Britain, a new institution emerged: the modern prison. Some prisons invested in scales. Upon entry, prisoners were measured and personal details documented. These meticulously compiled records afford a new vantage point from which we can peer into the dynamics of the household. Body measurements – height, weight, and body mass (weight adjusted for height) – connect to both patterns of consumption and health risk. Prison data thus speak to both gender and health inequality in the past. The paper juxtaposes a service economy (Wandsworth near London) with a modern manufacturing sector (Paisley near Glasgow) in order to contrast how economic form and opportunities in the market sector shaped relations and outcomes in the household sector. We find that families bargained over the allocation of resources; that bargaining position was influenced by economic value, mediated by maternal sacrifice; that this was an earner bias rather than gender bias; and that new industrial work for women and children supported a more egalitarian distribution that improved everyone's health status via superior heights and heavier weights. We examine Irish immigrants to assess cultural differences in family behaviour. Finally, the paper offers, for the first time, a detailed interpolation of Waaler's health risk for women.