Eating vegetables can lower inflammation levels regardless of physical activity, researchers find
A study, has explored the associations between fruit and vegetable (FV) intake and biomarkers of systemic inflammation in older adults and the results, say researchers, will strengthen public health efforts to promote a healthy lifestyle.
They say the findings highlight the benefits of a vegetable-rich diet that will mitigate age-related systemic inflammation in older adults. Systemic inflammation occurs when the immune system is constantly defending the body.
The study carried out by researchers at The School of Health Sciences in Sweden, said that while it is hypothesised that healthy diets rich in FV can modulate the inflammatory status in older adults, to determine the actual impact on inflammatory status other factors including weight and exercise need to be considered.
Several reports have shown that diets characterised by low fruit and vegetable intake are associated with mortality, cardiovascular diseases and type 2 diabetes mellitus.
The researchers said: “Moreover, studies have shown lowered cardiometabolic risk has been associated with higher consumption of either fruits, vegetables, or both fruits and vegetables. Therefore, diets rich in FV are globally recommended by major health organisations in order to prevent the burden of chronic diseases and promote health.
“During aging there is an elevated risk of cardiometabolic abnormalities, where a chronic inflammatory state characterized by slight elevations in the circulating levels of pro-inflammatory biomarkers has been implicated in the pathogenesis of age-related diseases. In this respect, the potential of FV to mitigate age-related chronic systemic inflammation has received particular attention.”
Based on a sample of 223 older adults between 65 and 70 years old, the following inflammatory biomarkers were assessed as part of the study: C-reactive protein (CRP), fibrinogen, interleukin-6 (IL-6), IL-10, IL-18, and monocyte chemoattractant protein-1 (MCP-1). The participants fruit and vegetable intake was assessed by self-report, and physical activity (PA) behaviours encompassing time spent sedentary and in moderate-to-vigorous PA (MVPA) were determined using accelerometers.
The study reported that associations between FV intake and inflammatory biomarkers were analysed using stepwise linear regression models while adjusting for several covariates, including health-related food groups, adherence to the MVPA guidelines, total sedentary time, and waist circumference.
Participants were asked how often they ate fruit and berries, vegetables and root vegetables, legumes, and root vegetables except potatoes. Fixed answering categories ranged from less than one serving per day to up to five servings per day or more.
In addition, a 90-item food-frequency questionnaire was used to determine total energy intake and intakes of health-related food groups, including whole-grains, fish, red or processed meats, fried potatoes, desserts and sweets, and sugar-sweetened beverages.
The researchers added: “While no significant associations were observed for the total FV intake, the vegetable intake was inversely associated with levels of IL6. In contrast, fruit intake was not associated with any inflammatory biomarker.
“Nonetheless, previous experimental work examining the effect of FV on established and novel biomarkers of systemic inflammation revealed conflicting results.”
Importantly, they wrote, in order to determine the actual role of FV it is necessary to assess the potential confounding impacts of physical activity behaviours. Indeed, it has been shown that time spent in moderate-to-vigorous physical activity may reduce levels of pro-inflammatory biomarkers, whereas time spent sedentarily has been detrimentally associated with systemic inflammation in older adults.
Additionally, they accpeted that if there is any beneficial effect on systemic inflammation driven by fruit or vegetable consumption, it still needs clarification.
They added: “Although low FV intakes are commonly reported in aging populations, there are relatively few studies specifically targeting older adults when depicting the role of FV on systemic inflammation."
The authors said this was what drove them to conduct this study as it was to explore the associations between intakes of fruits and vegetables and biomarkers of systemic inflammation in older adults, while considering objectively assessed PA behaviours.
Summing up they said: "In conclusion, our findings indicate beneficial associations between vegetable intake and levels of a pro-inflammatory biomarker in older adults, which strengthens public health efforts to promote vegetable-rich diets in older adults to mitigate age-related systemic inflammation."
Consumption of Vegetables Is Associated with Systemic Inflammation in Older Adults
Authors: Konstantinos-Georgios Papaioannou, Fawzi Kadi and Andreas Nilsson