Defining Nutritional and Functional Niches of Legumes: A Call for Clarity to Distinguish a Future Role for Pulses in the Dietary Guidelines for Americans.

Chelsea Didinger,Henry J. Thompson

doi:10.3390/nu13041100

Abstract

Legume food crops can contribute to the solution of diet-related public health challenges. The rich diversity of the botanical family Fabaceae (Leguminosae) allows legumes to fill numerous nutritional niches. Pulses (i.e., a subgroup of legumes including chickpeas, cowpeas, dry beans, dry peas, and lentils) are a nutrient-dense food that could play a key role in eliminating the dramatic underconsumption of dietary fiber and potassium, two dietary components of public health concern, all while maintaining a caloric intake that promotes a healthy weight status. However, incorrect use of terminology—in the commercial and scientific literature as well as in publications and materials prepared for the consuming public—creates confusion and represents a barrier to dissemination of clear dietary guideline messaging. The use of accurate terminology and a simple classification scheme can promote public health through differentiation among types of legumes, better informing the development and implementation of nutritional policies and allowing health care professionals and the public to capitalize on the health benefits associated with different legumes. Although inconsistent grouping of legumes exists across countries, the recently released 2020–2025 Dietary Guidelines for Americans (DGA) were chosen to illustrate potential challenges faced and areas for clarification. In the 2020–2025 DGA, pulses are included in two food groups: the protein food group and ‘beans, peas, lentils’ vegetable subgroup. To evaluate the potential of pulses to contribute to intake of key dietary components within calorie recommendations, we compared 100 kilocalorie edible portions of pulses versus other foods. These comparisons demonstrate the unique nutritional profile of pulses and the opportunity afforded by this type of legume to address public health concerns, which can be greatly advanced by reducing confusion through global harmonization of terminology.

Highlights

There are many edible legumes, at least 50, that have been identified at the level of genus-species in the botanical family Fabaceae (Leguminosae) and that are consumed by various populations around the world [1]
Advocacy for members of the Fabaceae food grouping— at the levels of genus, species, and cultivar within species—has contributed to artificial distinctions that have been used to focus attention on specific entities
To begin to rectify this situation, we adopted the following approach: (1) use an internationally accepted classification system from the Food and Agriculture Organization (FAO) as a basis for terminology [2]; (2) concentrate on predominant legume crops consumed by the global population as a whole [3]; and (3) use the United States as an example to illustrate the value of accurate and consistent use of terminology [4]

Summary

Introduction

There are many edible legumes, at least 50, that have been identified at the level of genus-species in the botanical family Fabaceae (Leguminosae) and that are consumed by various populations around the world [1]. Advocacy for members of the Fabaceae food grouping— at the levels of genus, species, and cultivar within species—has contributed to artificial distinctions that have been used to focus attention on specific entities (e.g., dry beans versus pulses when dry beans are a type of pulse). To begin to rectify this situation, we adopted the following approach: (1) use an internationally accepted classification system from the Food and Agriculture Organization (FAO) as a basis for terminology [2]; (2) concentrate on predominant legume crops consumed by the global population as a whole [3]; and (3) use the United States as an example to illustrate the value of accurate and consistent use of terminology [4]. We focus on legumes as whole foods, not as the ingredients into which they can be fractionated (e.g., pea protein powder)

Defining ‘Legume’

Are Allof

The United States Dietary Guidelines as a Case in Point

Findings

Distinction among Legumes Moving Forward