Individuals with overweight or obesity often have poor-quality diets that lack fruits and vegetables, whole grains, and legumes and contain excessive amounts of added sugar and saturated, compared with unsaturated, fatty acids (1), which can lead to higher risk of greater weight gain and chronic disease (2,3). Weight loss (WL) of 5% to 10% may prevent chronic disease (4); however, WL diets that restrict energy also reduce healthy food and micronutrient intake (5).The effect of higher protein intake during WL on health outcomes has been reported extensively, and there is evidence that it can promote a healthy body weight, attenuate loss of muscle mass (6,7), and reduce chronic disease (8-10). In addition, it was shown that dietary protein contributes to nutrient adequacy in the general population (11). However, the impact of self-selected dietary protein on diet quality has not been examined, to our knowledge, in a longitudinal study (11), such as during caloric restriction (CR). The link between protein intake and diet quality is important because diet quality is suboptimal in the US, and higher-protein WL diets are popular. In addition, the nutrient adequacy in populations consuming lower