Perspective: Defining Carbohydrate Quality for Human Health and Environmental Sustainability

Abstract

Plant foods are universally promoted for their links to improved human health, yet carbohydrate-containing foods are often maligned based on isolated, reductionist methods that fail to assess carbohydrate foods as a matrix of nutrients and food components. Currently accepted positive carbohydrate quality indices include plant food, whole-grain content, and dietary fiber, while negative health outcomes are linked to high intakes of added sugar and high glycemic index. More recently, negative health aspects have been linked to ultra-processed foods, which are often high in carbohydrates. Yet, carbohydrate staples such as grains and dairy products are both enriched and fortified, resulting in these carbohydrate foods containing important nutrients of concern such as dietary fiber, potassium, vitamin D, and calcium. This Perspective analyzes carbohydrate metrics used in dietary guidance and labeling and finds limitations in accepted indices included in standardized quality carbohydrate definitions and also proposes additional indices to benefit both human and environmental health. As nutrition recommendations shift away from a single-nutrient focus to a more holistic dietary pattern approach that is flexible and adaptable for each individual, it is necessary to determine the quality components that make up these patterns. This review concludes that current approaches that demonize staple carbohydrate foods do little to promote the recommended patterns of foods known to improve health status and reduce disease risk.

Keywords: added sugar; dietary patterns; environmental sustainability; nutrition; quality carbohydrates.

FIGURE 1

Carbohydrates contributed across food groups per capita per day (4).

FIGURE 2

Grouping of various criteria on what designates a quality carbohydrate (35) including context in which a food or meal is consumed, chemical composition of carbohydrate-containing food, and physiological impacts of consuming a particular carbohydrate food.

FIGURE 3

EAT-Lancet Commission on a system to determine quality carbohydrates including the spheres of assessment of nutrient adequacy, prediction of mortality rates, and impact on the environment (17).

FIGURE 4

Current and proposed indices layered into an algorithm to produce a holistic, standardized quality carbohydrate metric.