Self-selected dietary intake and association with achieved caloric restriction in CALERIE^™ 2

Caloric restriction (CR) reduces age-related risks, while diet quality is critical for healthy aging. Understanding how adults adjust diets to sustain CR and maintain nutrient adequacy can inform nutrition for healthy aging. Healthy adults (N = 220) were assigned to ad libitum (AL; N = 75) or 25% CR (N = 143; NCT00427193). Changes in macro/micronutrients and food groups collected via 6-day diet records at baseline and 12 months and their associations with %CR were evaluated. Compared to AL, CR participants achieved 15.2 ± 7.4%CR and lost 8.3 ± 3.1 kg. CR participants reduced fat (-16.5 g/day) and alcohol intake (-3 g/day), increased protein (1.2%EI/day) and carbohydrate (3.3%EI/day), and maintained micronutrient adequacy. CR participants increased fiber (8.6 g/day), reduced added sugars (-16.9 g/day) and fats (saturated -5.6 g/day; trans -1.2 g/day), and shifted toward a healthier dietary pattern by lowering refined grains, sugary beverages, sweets, and red meats while increasing fruits, vegetables, whole/mixed grains, and low-fat dairy (p < 0.05). Greater protein intake and lower intake of sauces/dressings/gravy at 12 months, and change in polyunsaturated fat and greater decreases in sauces/dressings/gravy intake from baseline to 12 months were most strongly associated with %CR. CR improved diet quality, demonstrating that CR can be implemented in a manner that reduces chronic disease risk.