Influence of protein intake from haem and non-haem animals and plant origin on inflammatory biomarkers among apparently-healthy adults in Greece.

Intake of different types of protein may be associated with differences in biomarkers among various populations. This work investigated the influence of protein intake from haem and non-haem animals as well as protein from plants on haematological and biochemical parameters in inflammation among apparently-healthy adults living in Greece, a Mediterranean country. Four hundred and ninety apparently-healthy subjects (46 +/- 16 years, 40% men), who consecutively visited Polykliniki General Hospital for routine examinations, voluntarily agreed to participate in the study (participation rate 85%). Demographic, anthropometric and lifestyle characteristics were recorded. Participants completed a valid, semi-quantitative food frequency questionnaire. Protein intake was classified into three sources: protein from haem animals, protein from non-haem animals, and protein from plant origin. Fasting blood samples were taken from all participants; uric acid, creatinine, lipids, cystatin C, haptoglobin, haemoglobin, haematocrit, iron, ferritin, white blood cells, monocytes, platelets, and C-reactive protein were measured. Protein intake from only haem animals was associated with increased haemoglobin and haematocrit levels (p < 0.05) whereas intake of protein from non-haem animals and plant origin was not associated with the investigated haematological and biochemical markers of low-grade chronic inflammation when lifestyle factors and overall dietary habits were taken into account. Intake of protein from only haem animals seems to be consistently associated with haematological markers. The confounding role of dietary habits and lifestyle variables on the tested parameters deserves further attention in future research.

The impact of demographic characteristics and lifestyle in the distribution of cystatin C values in a healthy greek adult population.

Background. The aim of the present study was to examine sources of variation for serum cystatin C in a healthy Greek population. Methods. Cystatin C together with basic clinical chemistry tests was measured in a total of 490 adults (46 ± 16 yrs, 40% males) who underwent an annual health check. Demographic, anthropometric, and lifestyle characteristics were recorded. Results. Higher values of cystatin C were observed among males (P = .04), participants aged over 65 years (P < .001), current smokers (P = .001) and overweight/obese participants (P = .03). On the contrary, alcohol consumption and physical activity seemed to have no influence on cystatin C levels (P = .61; P = .95, resp.). Conclusions. In interpreting serum cystatin C values in a healthy adult population, age, gender, Body Mass Index, and cigarette smoking need to be considered, and determination of reference ranges among distinct subpopulations seem to be prudent.