Oats are a rich source of β-glucan, a viscous, soluble fibre recognised for its cholesterol-lowering properties, and are associated with reduced risk of CVD. Our objective was to conduct a systematic review and meta-analysis of randomised-controlled trials (RCT) investigating the cholesterol-lowering potential of oat β-glucan on LDL-cholesterol, non-HDL-cholesterol and apoB for the risk reduction of CVD. MEDLINE, Embase, CINAHL and Cochrane CENTRAL were searched. We included RCT of ≥3 weeks of follow-up, assessing the effect of diets enriched with oat β-glucan compared with controlled diets on LDL-cholesterol, non-HDL-cholesterol or apoB. Two independent reviewers extracted data and assessed study quality and risk of bias. Data were pooled using the generic inverse-variance method with random effects models and expressed as mean differences with 95 % CI. Heterogeneity was assessed by the Cochran's Q statistic and quantified by the I 2 -statistic. In total, fifty-eight trials (n 3974) were included. A median dose of 3·5 g/d of oat β-glucan significantly lowered LDL-cholesterol (−0·19; 95 % CI −0·23, −0·14 mmol/l, P < 0·00001), non-HDL-cholesterol (−0·20; 95 % CI −0·26, −0·15 mmol/l, P < 0·00001) and apoB (−0·03; 95 % CI −0·05, −0·02 g/l, P < 0·0001) compared with control interventions. There was evidence for considerable unexplained heterogeneity in the analysis of LDL-cholesterol (I 2 = 79 %) and non-HDL-cholesterol (I 2 = 99 %). Pooled analyses showed that oat β-glucan has a lowering effect on LDL-cholesterol, non-HDL-cholesterol and apoB. Inclusion of oat-containing foods may be a strategy for achieving targets in CVD reduction.

Konjac glucomannan (KGM) is a viscous dietary fibre that can form a solid, low-energy gel when hydrated and is commonly consumed in a noodle form (KGM-gel). Increased meal viscosity from gel-forming fibres have been associated with prolonged satiety, but no studies to date have evaluated this effect with KGM-gel. Thus, our objective was to evaluate subsequent food intake and satiety of KGM-gel noodles when replacing a high-carbohydrate preload, in a dose-response manner. Utilising a randomised, controlled, cross-over design, sixteen healthy individuals (twelve females/four males; age: 26·0 (sd 11·8) years; BMI: 23·1 (sd 3·2) kg/m2) received 325 ml volume-matched preloads of three KGM-gel noodle substitution levels: (i) all pasta with no KGM-gel (1849 kJ (442 kcal), control), half pasta and half KGM-gel (1084 kJ (259 kcal), 50-KGM) or no pasta and all KGM-gel (322 kJ (77 kcal), 100-KGM). Satiety was assessed over 90 min followed by an ad libitum dessert. Compared with control, cumulative energy intake was 47 % (-1761 kJ (-421 kcal)) and 23 % (-841 kJ (-201 kcal)) lower for 100-KGM and 50-KGM, respectively (both P<0·001), but no differences in subsequent energy intake was observed. Ratings of hunger were 31 % higher (P=0·03) for 100-KGM when compared with control, and were 19 % lower (P=0·04) for fullness and 28 % higher (P=0·04) for prospective consumption when comparing 100-KGM to 50-KGM. Palatability was similar across all treatments. Replacement of a high-carbohydrate preload with low-energy KGM-gel noodles did not promote additional food intake despite large differences in energy. The energy deficit incurred from partial KGM-gel substitution may have relevance in weight loss regimens, and should be further evaluated beyond the healthy population.

NCT02626325.