What makes people choose low-carbohydrate, high-protein food (low-carb food), which is good for health but usually tastes bad? Using panel data on US beer consumption in which each consumption occasion is uniquely associated with various companion-based consumption contexts and exposure levels to diet information, we analyse the variations in consumers' preferences for low-carb food. The results show that there exist considerable gender differences in the preference variation under peer pressure. First, single females behave in a way they dislike drinking low-carb beer in front of friends, spouses and significant others. Second, male (both married and single) and married females pretend to choose low-carb beer when accompanied by spouses or significant others. Finally, the elasticity of demand for healthy food with respect to news articles about low-carb diets is positive, yet with substantial differences in the degree of elasticity across demographic groups.