Dietary factors and biomarkers of systemic inflammation in older people: the Lothian Birth Cohort 1936

Epidemiological studies have reported inverse associations between various single healthy diet indices and lower levels of systemic inflammation, but rarely are they examined in the same sample. Our aim was to investigate the potential relationships between biomarkers of inflammation (C-reactive protein (CRP) and fibrinogen) and overall foods (dietary patterns), single foods (fruits, vegetables), and specific nutritive (antioxidants) and non-nutritive (flavonoids) food components in the same narrow-age cohort of older adults. The dietary intake of 792 participants aged 70 years from the Lothian Birth Cohort 1936 was assessed using a 168-item food frequency questionnaire. Models were adjusted for age, sex, childhood cognitive ability, lifestyle factors and history of disease. Using logistic regression analyses, CRP (normal versus elevated) was favourably associated (at P < 0.05) with the Health-aware (low-fat) dietary pattern (unstandardised b = -0.200; OR 0.82; 95% CI 0.68 0.99), and fruit intake (b = -0.100; OR 0.91; 95% CI 0.82 0.99), including flavonoid-rich apples (b = -0.456; OR 0.63; 95% CI 0.439 0.946). Using linear regression analyses, fibrinogen (continuous) was inversely associated (at P < 0.05) with the Mediterranean dietary pattern (standardised β = -0.100), fruit intake, (β = -0.083), and fruit and vegetable intake combined (β = -0.084). We saw no association between food components—antioxidant nutrients, or specific flavonoid subclasses—and inflammatory markers. In this cross-sectional study, nutrient dense dietary patterns were associated with lower systemic inflammation in older people. The results are consistent with dietary guidelines which promote a balanced diet based on a variety of plant-based foods.