Background
While increasing longevity is highly desirable, it also brings the challenge of more years lived with disease, as many cardio-metabolic conditions typically arise in older age—placing additional strain on healthcare resources. Despite strong evidence linking modifiable lifestyle factors, particularly diet, to disease risk, preventive initiatives remain underprioritized in policy. Whole grains, which are affordable, sustainable, and easy to incorporate into daily diets, have been consistently associated with a reduced risk of colorectal cancer, type 2 diabetes, and cardiovascular disease.
 
Objectives
We estimated the association between whole-grain intake and healthcare expenditure related to colorectal cancer (CRC), type 2 diabetes (T2D), and cardiovascular disease (CVD). Specifically, we assessed the association between observed intake and hypothetical increases in whole-grain consumption on disease incidence and associated costs.
 
Methods
We utilized data from the Danish “Diet, Cancer and Health” (DCH) cohort comprising middle-aged adults with baseline dietary assessments in 1993–1997 followed up through Danish health registries until end of 2018. Healthcare costs—including medication, hospital admissions, and productivity loss—were accrued for each year lived with CRC, T2D, and CVD, respectively, and estimated across different levels of whole-grain consumption (16–32 g/d (1–2 servings), 32–48 g/d, 48–64 g/d, and >64 g/d (>4 servings)). Stratified by gender, microsimulation based on an illness-death model was used to estimate potential cost savings from population-level increases in whole-grain intake. The transition models were adjusted for BMI, education, cohabitation status, physical activity, smoking, and alcohol consumption.
 
Results
The strongest cost-saving effects of increased whole-grain intake were seen among men for all outcomes. Over the follow-up period, the observed average healthcare cost per DCH male cohort participant was 1,413 Euro (95% CI: 1,332–1,594€) due to CRC, 2,742€ (95%CI: 2,627–2,855€) due to T2D, and 13,568€ (95% CI:13,194–13,950€) due to CVD. For simulated whole-grain intakes, the difference in healthcare cost per person was 289€ for CRC, 548€ T2D and 2,025€ for CVD, when comparing the lowest to the highest serving-defined whole-grain intake. The results were less pronounced for T2D among women (difference of 224€), with no difference for CRC or CVD.
 
Conclusions/Implications
This study presents the first health economic analysis using observed whole-grain intake in a prospective Danish cohort with 20 years of follow-up. Increased whole-grain intake was associated with lower healthcare costs for CRC, T2D, and CVD among men and for T2D among women. These results underscore the potential of dietary prevention strategies to alleviate the growing economic burden on healthcare systems, especially in aging populations. These findings provide empirical support for the economic benefits of dietary prevention strategies, complementing previous theoretical models from Australia, Finland, and the USA.