Individual- and supply-level macronutrient intakes are well correlated over a 50-year period (1961-2011) in 18 countries in Asia, North America, and Europe.

ABSTRACT

Reliable information on dietary trends is essential. We compared individual-level dietary estimates for total energy, carbohydrate, fat, and protein intake over time with national supply data from the Global Expanded Nutrient Supply Model (186 paired estimates from 1961 to 2011, 18 countries). We hypothesized that supply data would overestimate individual measures and that the two measures would be weakly correlated. Individual- and supply-level estimates were compared using Spearman correlation coefficients and linear mixed-effect models were used to estimate the differences between measures. Overall, the correlations between individual- and supply-level measures were moderate for energy (rs = 0.34) and carbohydrate (rs = 0.39), strong for fat (rs = 0.85), and protein (rs = 0.69). Trends in total energy measured by individual-level surveys and total energy supply were positively correlated in 38.9% of countries, whereas trends in macronutrients aligned between estimates in most countries. Supply-level dietary data overestimated individual-level intakes, especially in higher income countries in Europe and in the United States. In the United States, supply-level data exceeded individual-level estimates by 26.3% to 29.9% for energy, carbohydrate, and fat, whereas protein estimates were similar between measures. In Europe, supply-level estimates overestimated individual-level intake by 19.9% for energy, 17.0% for carbohydrate, 13.7% for fat, and 7.7% for protein, whereas estimates for energy and macronutrients were similar in Asia. In Asia and lower income countries, our findings generally support the use of supply-level data in the absence of individual-level data, though this finding may be related to smaller sample size and differences in underlying national statistics that inform supply data.