Primary care

Frequency of eating and concentrations of serum cholesterol in the Norfolk population of the European prospective investigation into cancer (EPIC-Norfolk): cross sectional study

Silvia M O Titan, visiting research fellow, ^a Sheila Bingham, deputy director, ^b Ailsa Welch, research associate, ^a Robert Luben, research associate, ^a Suzy Oakes, research associate, ^a Nicholas Day, MRC professor of epidemiology, ^a Kay-Tee Khaw, professor of clinical gerontology. ^a

^a Institute of Public Health, University of Cambridge, Cambridge CB2 2SR, ^b MRC Dunn Human Nutrition Unit, Cambridge CB2 2XY

Correspondence to: K-T Khaw, Clinical Gerontology Unit, University of Cambridge, Addenbrooke's Hospital Box 251, Cambridge CB2 2QQ kk101{at}medschl.cam.ac.uk

Objectives: To examine the relation between self reported eating frequency and serum lipid concentrations in a free living population.
Design: Cross sectional population based study.
Setting: Norfolk, England.
Participants: 14 666 men and women aged 45-75 years from the Norfolk cohort of the European prospective investigation into cancer (EPIC-Norfolk).
Main outcome measures: Concentrations of blood lipids.
Results: Mean concentrations of total cholesterol and low density lipoprotein cholesterol decreased in a continuous relation with increasing daily frequency of eating in men and women. No consistent relation was observed for high density lipoprotein cholesterol, body mass index, waist to hip ratio, or blood pressure. Mean cholesterol concentrations differed by about 0.25 mmol/l between people eating more than six times a day and those eating once or twice daily; this difference was reduced to 0.15 mmol/l after adjustment for possible confounding variables, including age, obesity, cigarette smoking, physical activity, and intake of energy and nutrients (alcohol, fat, fatty acids, protein, and carbohydrate).
Conclusions: Concentrations of total cholesterol and low density lipoprotein cholesterol are negatively and consistently associated with frequency of eating in a general population. The effects of eating frequency on lipid concentrations induced in short term trials in animals and human volunteers under controlled laboratory conditions can be observed in a free living general population. We need to consider not just what we eat but how often we eat.