The association between the dietary inflammatory index and cardiorespiratory fitness in United States young adults: a cross-sectional study from the National Health and Nutrition Examination Study, 1999-2004

Bo Wu; Lanlan Qiu; Yun Lin; Qian Lin; Yuxiong Pan

doi:10.3389/fnut.2024.1442710

The association between the dietary inflammatory index and cardiorespiratory fitness in United States young adults: a cross-sectional study from the National Health and Nutrition Examination Study, 1999-2004

Front Nutr. 2024 Sep 26:11:1442710. doi: 10.3389/fnut.2024.1442710. eCollection 2024.

Authors

Bo Wu¹, Lanlan Qiu², Yun Lin¹, Qian Lin¹, Yuxiong Pan¹

Affiliations

¹ Department of Cardiology, Longyan First Affiliated Hospital of Fujian Medical University, Longyan, China.
² Department of Cardiology, Longyan People's Hospital, Longyan, China.

Abstract

Background: Cardiorespiratory fitness (CRF) is a vital indicator of overall health and cardiovascular efficiency. Systemic inflammation significantly impacts CRF, and reducing systemic inflammation may serve as an effective strategy to improve CRF. Diet plays a crucial role in systemic inflammation, but daily dietary intake typically involves multiple elements rather than a single nutrient. The Dietary Inflammatory Index (DII) provides an overall assessment of dietary inflammation on the basis of the anti-inflammatory and pro-inflammatory effects of the nutrients consumed. However, the relationship between DII and CRF is not yet well understood.

Aims: To examine the association between the DII and CRF.

Method: This study analyzed 3,087 participants from the National Health and Nutrition Examination Survey (NHANES) between 1999 and 2002. The study subjects were divided into three distinct groups by DII tertile: T1 (n = 1,027), T2 (n = 1,029), and T3 (n = 1,031). The associations between DII levels and CRF were examined via logistic regression analysis and restricted cubic splines (RCSs).

Results: Elevated DII scores were significantly linked to low CRF levels. Compared with those in the lowest tertile, participants in the highest DII tertile exhibited a greater prevalence of low CRF (T1: 10.85%, T2: 16.32%, T3: 19.31%). In the model with full adjustments, elevated scores on the DII were consistently linked with a heightened likelihood of low CRF (OR: 1.17, 95% CI: 1.07-1.28; P < 0.001). Compared with those in the T1 group, participants with higher DIIs had an increased risk of lower CRF (T2: OR: 1.42, 95% CI: 1.01-2.01, P = 0.046; T3: OR: 1.71, 95% CI: 1.22-2.40, P = 0.003). Additionally, a significant interaction (P = 0.045) between sex and the DII for low CRF was observed within the population.

Conclusion: A higher DII score is linked to an elevated risk of low CRF. Moreover, sex can impact CRF, with women being more prone to low CRF.

Keywords: NHANES; cardiorespiratory fitness; cross-sectional study; dietary inflammatory index; inflammatory.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This research was funded and supported by the Longyan City Science and Technology Plan Project (grant numbers: 2022LYF17026 and 2023LYF17049).