Associations between meal and snack frequency and diet quality and adiposity measures in British adults: findings from the National Diet and Nutrition Survey

Objective: To examine how different definitions of meals and snacks can affect the associations of meal frequency (MF) and snack frequency (SF) with dietary intake and adiposity measures. Design: Based on 7 d weighed dietary record data, all eating occasions providing >= 210 kJ of energy were divided into meals or snacks based on contribution to energy intake (>= 15 % or < 15 %) or time (06.00-10.00, 12.00-15.00 and 18.00-21.00 hours; other). Diet quality was assessed using the Healthy Diet Indicator (HDI) and Mediterranean Diet Score (MDS). Setting: Great Britain. Subjects: British adults aged 19-64 years (n 1487). Results: MF based on energy contribution was associated with higher intake of dietary fibre, lower intakes of non-milk extrinsic sugars and alcohol, and higher HDI (only men) and MDS. MF based on time was associated with higher HDI and MDS in women only. Conversely, irrespective of the definition of snacks, SF was associated with higher intakes of confectionery and alcohol, lower intakes of cereals, protein, fat and dietary fibre, and lower HDI (except for SF based on energy contribution in women) and MDS. After adjustment for potential confounders, MF based on time, but not MF based on energy contribution, was positively associated with BMI and waist circumference in men only. SF was positively associated with BMI and waist circumference, irrespective of the definition of snacks. Conclusions: Higher SF was consistently associated with lower diet quality and higher adiposity measures, while associations with MF varied depending on the definition of meals and sex.