C-Reactive Protein and Diet Quality in Children

Abstract

This review examines the relationship(s) between several dietary aspects (i.e. food consumption, dietary biochemical markers and nutrient intake through food or supplements) and C-reactive protein (CRP) concentration in childhood populations. The first paper published on this topic was in 2005, and until 2011, only ten papers have been published, all of which are reviewed here.

The sample sizes of studies reviewed varied from less than 100 (three studies) to more than 1,000 participants (three studies). The remaining four studies included between about 100–300 participants. Nine of the ten studies were cross-sectional, and one was an intervention study. In the majority of the reviewed studies, foods and nutrients that are generally considered as health-protecting (e.g. grains, vegetables, fruit, dairy fatty acids, eicosapentaenoic acid, zinc, iron, magnesium and folate) were inversely related to CRP concentration (in 7 out of the 10 reviewed studies), whereas foods and nutrients that are generally considered as unhealthy (e.g. saturated fat, meat and French fries) were not significantly related to CRP concentration (in four out of six studies that reported such associations). In the remaining two studies reviewed, there was a positive effect of total and different types of fatty acids to CRP and an additive effect of foods, assessed via dietary indices, considered ‘unhealthy’, to increasing CRP concentration. In summary, preliminary evidence shows that a healthy diet may be protective against inflammation as shown by the lower CRP concentration; nevertheless, since the number of studies conducted is limited and there is considerable heterogeneity in the dietary markers used, the participants’ age and the sample sizes, definitive conclusions cannot be drawn. With regard to ‘unhealthy’ dietary components or markers, the evidence is less clear; nevertheless, there is some evidence pointing to the direction of focusing research on the additive role of foods or components, generally considered ‘unhealthy’. In conclusion, although there is some evidence on the role of diet on CRP concentration in children, more research is needed in order to better understand this relationship.