A large study by Friedman School of Nutrition Science and Policy at Tufts University and the Harvard T.H. Chan School of Public Health of the diets of over 43,000 American adults, published in July 2019, found that people are still consuming, “too many low-quality carbohydrates and more saturated fat than recommended”.

Broadly, the study covered low-quality carbohydrates (primarily added sugar) and high-quality carbohydrates (primarily whole grains), plant protein (primarily whole grains and nuts), and polyunsaturated fat.

They found, “42% of energy intake was still derived from low-quality carbohydrates and the intake of saturated fat remained above 10% of energy.”


“Trends in Dietary Carbohydrate, Protein, and Fat Intake and Diet Quality Among US Adults, 1999-2016”