A CHO/fibre diet reduces and a MUFA diet increases postprandial lipaemia in type 2 diabetes: no supplementary effects of low-volume physical training

Abstract

The aim of the study was to evaluate the effects of a supervised physical training added to a healthy diet-rich in either carbohydrate and fibre (CHO/fibre) or monounsaturated fatty acids (MUFA)-on postprandial dyslipidaemia, an independent cardiovascular risk factor particularly relevant in type 2 diabetes (T2D). Participants were forty-five overweight/obese subjects with T2D, of both genders, in good blood glucose control with diet or diet+metformin, with normal fasting plasma lipids. According to a parallel groups 2 × 2 factorial design, participants were randomized to an 8-week isoenergetic intervention with a CHO/fibre or a MUFA diet, with or without a supervised low-volume aerobic training programme. The main outcome of the study was the incremental area under the curve (iAUC) of lipid concentrations in the plasma chylomicron+VLDL lipoprotein fraction, isolated by preparative ultracentrifugation (NCT01025856). Body weight remained stable during the trial in all groups. Physical fitness slightly improved with training (VO2 peak, 16 ± 4 vs. 15 ± 3 ml/kg/min, M ± SD, p < 0.05). Postprandial triglyceride and cholesterol iAUCs in plasma and chylomicron+VLDL fraction decreased after the CHO/fibre diet, but increased after the MUFA diet with a significant effect for diet by two-way ANOVA (p < 0.05). The addition of exercise training to either dietary intervention did not significantly influence postprandial lipid response. A diet rich in carbohydrates and fibre reduced postprandial triglyceride-rich lipoproteins compared with a diet rich in MUFA in patients with T2D. A supervised low-volume physical training did not significantly influence these dietary effects.

Impact of High-Carbohydrate Diet on Metabolic Parameters in Patients with Type 2 Diabetes

“…Adherence rate of currently-published RCT of HC diets was 65%–84%, and this was not inferior to the LC diet adherence rate [22,23,26]. Moreover, studies of HC diet with high fiber showed good adherence of participants [36,37]. …”

“…An RCT by Bozzetto L et al evaluated the effects of a diet rich in either carbohydrate/fiber with a low GI (moderate carbohydrate/fiber diet; C:F:P = 52%:30% (MUFA 16%):18%, 28 g/1000 kcal for fiber, GI (bread reference) of 48 and mean GL of 15,651) or rich in monounsaturated fatty acids (MUFA diet; C:F:P = 40%:42% (MUFA 28%):18%, 10 g/1000 kcal for fiber, GI (bread reference) of 60 and mean GL of 20,326) on postprandial dyslipidemia in 38 patients with T2DM [37]. After eight weeks, postprandial triglyceride levels decreased after a moderate carbohydrate diet rich in fiber, but increased after MUFA diet ( p < 0.05).…”

Low energy density diet, weight loss maintenance, and risk of cardiovascular disease following a recent weight reduction program: A randomized control trial

“…[36] The effects of dietary fiber on reducing the body fat stores might be due to reducing the energy intake and chylomicron concentrations and increasing the fat excretion. [37] Moreover, high fiber intake will increase the blunted postprandial, which consequently improves the insulin sensitivity. [38]…”

Physiology in Medicine: update on lifestyle determinants of postprandial triacylglycerolemia with emphasis on the Mediterranean lifestyle

“…Several studies have compared the effects on PPL of a diet high in total fat and MUFA (HFMUFA) (olive oil) vs. low in fat and high in carbohydrates (LFHC) and/or vs. a diet high in fat and SFA (HFSFA) (butter). Many (21,24,33,34,39,46,68,69,76,79,90), but not all (4,14,20,26,65,70,71,85), found that the HFMUFA diet was superior to the other two diets in several aspects of postprandial TAG metabolism in both healthy and nonhealthy volunteers (Tables 1 and 2).…”

“…Small sample size, no washout period, only small differences (ϳ3%) between diets in MUFA, higher fiber content in LFHC, or short postprandial time may account for the results of these studies. More importantly, in some of these studies, test meal composition was according to diet composition, and the LFHC meal had less (14,20), or no (65) fat compared with the HFMUFA meal; therefore, this effect was expected, since meal total fat amount is the main determinant of PPL (14,20,65). However, other studies found benefits of a HFMUFA vs. a LFHC diet, even if the test meal was according to diet composition and therefore of greater fat (24,33,68,79).…”