The North/South Ireland Food Consumption Survey: the dietary fibre intake of Irish adults

Abstract

Objective: Mean daily intakes of dietary fibre (DF, Southgate) and non-starch polysaccharide (NSP, Englyst) are estimated in a representative sample of adults aged 18-64 years in Ireland. The contribution of food groups to DF and NSP intake is reported and fibre intakes are compared with dietary recommendations and with intakes in some European countries.

Design: Food consumption was estimated using 7-day food diaries for a representative sample (n=1379); 662 men, 717 women) of 18-64 year old adults in the Republic of Ireland and Northern Ireland selected from the electoral register. DF and NSP intakes were estimated from tables of food composition.

Results: The mean daily intake of DF in the total sample was 20.2 g (standard deviation (SD) 7.8) [23.2 g (SD 8.5) in men, 17.4 g (SD 5.9) in women] or 2.24 g MJ(-1) (SD 0.7) [2.16 g MJ(-1) (SD 0.7) in men, 2.33 g MJ(-1) (SD 0.7) in women]. Mean daily intake of NSP was 14.8 g (SD 6.2) [16.7 g (SD 6.8) in men, 13.0 g (SD 5.0) in women] or 1.65 g MJ(-1) (SD 0.6) [1.56 g MJ(-1) (SD 0.6) in men, 1.74 g MJ(-1) (SD 0.6) in women]. The main food groups that contributed to mean daily intake of DF (NSP) in the sample were breads 31% (23%), potatoes 19% (23%), and vegetables 17% (19%). Absolute intakes of DF and NSP were higher (P<0.001) in men than women; however, women overall consumed more (P<0.001) fibre-dense diets than men. Women aged 18-35 years consumed less (P<0.01) DF and NSP (g) than women aged 36-64 years. Both men and women aged 18-35 years consumed less (P<0.01) fibre-dense diets than men and women aged 36-64 years. The NSP intake was below the nutritional goal of 18 g day(-1) in 77% of adults and below the minimum of the recommended range (12 g day(-1) in 37% of the total sample. Compliance (i.e. the maximum number of individuals whose collective mean daily intake corresponded to the population goal) with the (UK) population goal for an average intake of 18 g day(-1) NSP was achieved by a greater proportion of the population (63%) than compliance with the (German) dietary fibre recommendation of 30 g day(-1) (27%) or the (Nordic) recommendation of 3 g MJ(-1) day(-1) (33%).

Conclusion: DF (NSP) intakes were lower than dietary recommendations in a substantial proportion of the population. This is likely to contribute to impaired bowel function and constipation, which in turn may contribute to increased risk of chronic gastrointestinal disease.