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Inverse associations between whole-grain food consumption and risk of CVD, some cancers and type 2 diabetes have been reported. However, there are few reports of whole-grain intake, particularly among young people. The objective of the present study was to estimate whole-grain intake in a nationally representative sample of young people aged 4-18 years living in Great Britain. Whole-grain intake was estimated using 7 d weighed dietary records from 1583 young people who participated in the cross-sectional National Diet and Nutrition Survey in 1997. Whole-grain intake was quantified from the consumption of all foods containing $10 % whole-grain content. Median whole-grain intake was 7 g/d (interquartile range 0-19 g/d), with a corresponding mean of 13 (SD18) g/d. Intake was significantly lower among young people whose head of household had a manual occupation, but did not differ significantly by sex, age, region or season. There was no whole-grain intake for 27 % of participants. The percentages for less than one and less than three 16 g amounts of wholegrain intake per d were 70 and 94, respectively, while corresponding percentages based on 20 g amounts were 76 and 97. Foods with ,51 % whole-grain content provided 28 % of whole-grain intake overall, with a higher percentage in older adolescents. The main sources of whole-grain intake were breakfast cereals (56 %) and bread (25 %). The present study provides the first quantification of absolute whole-grain intake from all significant food sources in any representative age group in the UK. Although there is some debate regarding the quantity of whole grains required for good health, whole-grain intake among British young people is low.Whole grain: Intake and food sources: Children: Great Britain Epidemiological evidence suggests an inverse association between the consumption of whole-grain foods and the risk of premature all-cause mortality (Jacobs et al. 1999(Jacobs et al. , 2001) and various chronic diseases. Prospective studies have found that habitual consumption of whole-grain foods is associated with reduced risk of some (mainly gastro-intestinal) types of cancer (Jacobs et al.

Epidemiological evidence suggests that higher consumption of whole-grain foods can significantly reduce the risk of chronic diseases such as CVD, type 2 diabetes and some cancers. The present study compares whole-grain intake of 2086 adults aged 16 -64 years from the 1986 -7 Dietary and Nutritional Survey of British Adults with that of 1692 adults aged 19-64 years from the 2000 -1 National Diet and Nutrition Survey. For each survey, whole-grain intake was estimated from consumption of all foods containing $10 % whole-grain content (as DM/fresh weight of food) from 7 d weighed dietary records. In 1986 -7, median whole-grain intake was 16 (interquartile range 0 -45) g/d v. 14 (interquartile range 0-36) g/d in 2000-1 (P,0·001). In 1986 -7, 77 % of adults had less than three 16 g amounts of whole-grain intake/d; 25 % reported no whole-grain intake. In 2000-1, corresponding percentages were 84 and 29 %, respectively. Foods with , 51 % whole-grain content provided 18 % of whole-grain intake in 1986-7 v. 27 % in 2000 -1 (P,0·001). In both surveys, whole-grain intake was significantly lower among adults with a manual v. non-manual occupation (indicative of lower socio-economic status) and among smokers v. non-smokers, independent of occupational social class. In 1986 -7, whole-grain breakfast cereals and wholemeal bread contributed 28 and 48 % of whole-grain intake, respectively, v. 45 and 31 % in 2000 -1. At each time, one-third of adults consumed neither of these two largest contributors to whole-grain intake. Findings from the present study suggest that whole-grain intake of British adults was low in 1986-7 and became even lower over the subsequent decade.Whole-grain intake: Food sources: Great Britain

This experiment investigated the effect of intraruminal infusion of propionic acid on ruminal VFA metabolism and the absorption of nutrients by the mesenteric- and portal-drained viscera of seven Friesian steers, average BW 127 kg, fed a dried grass-pellet diet. Each received by random allocation 0 (control), .5, or 1.0 mol of propionic acid/d for 7 d. Ruminal acetate and propionate irreversible loss rates and carbon exchange between VFA and CO2 were measured during continuous intraruminal infusions of 2-14C-acetic acid and 2-14C-propionic acid. Ruminal acetate irreversible loss rate was not affected by propionic acid infusion (overall mean 8.09, error mean square [EMS] 2.68 mol/d), whereas propionate irreversible loss increased incrementally with PA supply (3.22 vs 4.16, EMS .61 mol/d, for control and 1.0 mol of propionic acid/d, respectively, P = .09). Glucose irreversible loss rate was increased at the highest level of PA infusion (2.84, 2.83, and 3.22, EMS .06 mol/d, for control, .5, and 1.0 mol of propionic acid/d, respectively; P = .02 for control vs .5 + 1.0), although the proportion of glucose irreversible loss derived from propionate remained constant (.6). Net absorption into venous blood showed that propionate was extensively metabolized in the rumen wall and that the tissues of the small intestine utilized acetate. Utilization of glucose was reduced in portal tissues as a result of intraruminal infusion, and the data were used to derive a model of glucose and lactate interrelationships in gut tissues.

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