Food Rx: Integrating horticulture research to improve nutrition and health

Abstract

It is clear that the escalating epidemic of insulin resistance and type 2 diabetes has reached a crisis level in the United States, that overweight and obesity are drivers, and that diets and the food system have major roles. It is also clear that nutrition and medical research point to increased healthful fruit and vegetable intake as a key part of any strategy to manage the crisis. But although increasing healthful intake entails both expanding production of fruits and vegetables and improving their healthful characteristics, horticulture has generally been sidelined or taken for granted when strategies are envisioned. This article makes the case that horticulture research and practice can and should be equal partners with nutrition and medicine in the pressing search for effective crisis-management strategies. To do so, it first "runs the numbers" for the scale of the crisis, for trends in fruit and vegetable intake and production, for the scant federal support for horticultural crop production and research, and for horticulture research's high return on investment. The article then sketches a roadmap to integrate horticulture research and community outreach with nutrition and healthcare, stressing new opportunities. The goal is a US food system that i) makes healthful fruits and vegetables accessible, affordable, and appealing for all and ii) complements a healthcare system spanning patient-based to population-based nutrition.

Keywords: food is medicine; fruits and vegetables; horticulture; obesity; type 2 diabetes.

Fig. 1.

The US obesity/overweight/diabetes epidemic by the numbers. (A) 60 y trend in adult obesity (arrows mark the release dates of editions of the DGA; percent of adults and young people with overweight or obesity (2017 to 18); percent of adults (2017 to 20) and adolescents (2005 to 16) with diabetes and prediabetes. (B) Estimated years of life lost according to age at diagnosis of type 2 diabetes relative to people without diabetes. (C) Prevalence of diabetes complications among people diagnosed with diabetes: peripheral neuropathy (DPN), cardiovascular disease (CVD), chronic kidney disease (CKD), and retinopathy (DR). Data are for various years 2007 to 2018. (D) Total economic costs of diabetes (direct medical costs and attributable indirect costs) relative to military spending in 2022. (E) Percent of youth eligible/ineligible for military service in 2020. (F) Estimated economic impacts of not meeting the US recommended daily fruit and vegetable intake on cardiovascular deaths alone (2018). Data sources are in Dataset S1.

Fig. 2.

US fruit and vegetable intake and production by the numbers. (A) Percent of adults in 2019 getting the DGA recommended daily intake of fruits (2 servings) and vegetables (3 servings). (B) Median frequencies in 2019 of fruit and vegetable intake among adults. (C) 50 y trends in per capita fruit and vegetable availability. Arrows next to the vertical axis show roughly what fruit (pink) and vegetable (green) supplies would need to be to meet recommended intakes for the whole US population. (D) Increases over 40 y in real costs of fruits and vegetables vs. commodity crop-based foods as reflected by the Consumer Price Index (CPI, 1982-4 = 100). (E) Consumption of fruits and vegetables vs. ultraprocessed foods (UPFs) by US adults in 2002 and 2018, expressed as percentages of total energy (kcal) intake. (F) Approximate estimates of shortfalls in US domestic production of representative healthful fruits and vegetables relative to amounts needed to give the population 1 serving per day. (G) 40 y trends in imports as a share of the US supply of fresh fruits and vegetables. (H) Area of US cropland planted to fruits and vegetables in 2017 relative to major commodity crops. Data sources are in Dataset S2.

Fig. 3.

US federal support for fruit and vegetable research and production by the numbers. (A) Breakdown of the 2018 Farm Bill showing the small fraction for support of horticultural crop research and production relative to nutrition programs and commodity crops. (B) Approximate estimates of research funding for horticulture from the 5 y 2018 Farm Bill vs. NIH research funding for the same 5 y from the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) and for cardiovascular disease (CVD) from the National Heart, Lung, and Blood Institute (NHLBI); CVD research was estimated as 50% of the NHLBI total. (C) 50 y trends in publications per year (a proxy for research investment quantification) for Zea mays (maize) and Fragaria (cultivated strawberries and close relatives). (D) 50 y trends in US average yield per acre for maize and strawberries relative to yields in 1970 (= 1). A rough estimate of the 18-fold greater ROI on research on strawberry vs. maize (3× more yield advance for 6× less research) is between C and D. Data sources are in Dataset S3.

Fig. 4.

Roadmap for integrating horticulture research and practice with healthcare and nutrition with respect to research needs and opportunities and practical needs and opportunities.