Links between vitamin D status and C-reactive protein (CRP), a measure of inflammation in older adults, have been shown in a new study from ageing experts at Trinity College Dublin and the University of Limerick.

CRP can be a blood measure of inflammation in the body. High levels can indicate infection while lower – but still higher than normal – levels can indicate low-grade inflammation. Scientists think that this low-grade constant inflammation, common in older adults, can lead to a slow accumulation of damage. This may be a major risk factor for many of the chronic diseases of ageing including cardiovascular disease, mental health decline, diabetes etc. Anything that could help decrease CRP levels in the blood may have a positive impact on chronic disease prevention. 

Vitamin D has recently has been linked with immune function. Previous research from the Irish Longitudinal Study On Ageing (TILDA) has shown that one in 8 older Irish adults are deficient in the vitamin with those most at risk including the oldest, smokers, those with low household incomes, smokers, those living with obesity. Previous work from Professor Rose Anne Kenny and Dr Laird has also reported on the association of vitamin D with COVID. 

The new study used data from TILDA, and examined participants aged 50 years and over who were assessed at Wave 1 of the study and who provided measurement of vitamin D and CRP. It found that having a sufficient vitamin D status reduced the risk of a high CRP level compared with being deficient. 

Dr Eamon Laird, Lead Author of the study said: “This study is very important given the high prevalence of vitamin D deficiency and chronic disease in older adults living in Ireland. Our findings along with previous trials in this area suggest that optimising vitamin D status to above deficient levels could help to benefit the inflammation pathway in community dwelling older adults. 

"Given that the FSAI just recently changed the vitamin D intake guidelines for older adults to 15ug per day (600 IU), our findings should provide further reassurance for policy makers to show that maintaining a sufficient vitamin D status is actually linked with lower levels of inflammation and did not increase the risk. 

“Remember vitamin D is one component: in order to have the lowest risk of inflammation people should think about vitamin D in combination with regular physical activity, healthy lifestyle, adequate sleep and social interactions."

The study is published in the PLOS ONE Journal ‘Vitamin D status & Associations With Inflammation In Older Adults’ can be found here: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0287169