Caloric restriction (CR) without malnutrition increases longevity and delays the onset of age-associated disorders in short-lived species, from unicellular organisms to laboratory mice and rats. The value of CR as a tool to understand human ageing relies on translatability of CR's effects in primates. Here we show that CR significantly improves age-related and all-cause survival in monkeys on a long-term ~30% restricted diet since young adulthood. These data contrast with observations in the 2012 NIA intramural study report, where a difference in survival was not detected between control-fed and CR monkeys. A comparison of body weight of control animals from both studies with each other, and against data collected in a multi-centred relational database of primate ageing, suggests that the NIA control monkeys were effectively undergoing CR. Our data indicate that the benefits of CR on ageing are conserved in primates.
The aim of the study was to compare the effect of the administration of a mixture of fibres on body weight-loss, satiety, lipid profile and glucose metabolism. We included 200 overweight or obese patients in a parallel, double-blind, placebo-controlled clinical trial, who were randomised to receive, in the context of an energy-restricted diet for a period of 16 weeks, a mixed fibre dose (3 g Plantago ovata husk and 1 g glucomannan) twice (b.i.d. group) or three times daily (t.i.d. group) or placebo. Weight change was the primary efficacy endpoint. Satiety, dietary compliance, lipid profile, glucose tolerance, insulin resistance and high-sensitivity C-reactive protein were secondary endpoints. Weight loss tended to be higher after both doses of fibre (-4.52 (SD 0.56) and -4.60 (SD 0.55) kg) than placebo (-0.79 (SD 0.58) kg); the differences in changes between groups were not statistically significant. Postprandial satiety increased in both fibre groups compared to the placebo. The differences between groups in LDL-cholesterol levels were significant (P = 0.03), with greater reductions in the two fibre-supplemented groups (-0.38 (SD 0.10) and -0.24 (SD 0.09) mmol/l in the b.i.d. and t.i.d. groups v. -0.06 (SD 0.09) mmol/l in placebo group). A similar pattern was observed for changes in total cholesterol:HDL-cholesterol and HDL-cholesterol:LDL-cholesterol ratios. Interventions were well tolerated and had no effects on HDL-cholesterol, glucose and insulinconcentrations, glucose tolerance or high-sensitivity C-reactive protein. In conclusion, a 16-week dietary supplement of soluble fibre in overweight or obese patients was well tolerated, induced satiety and had beneficial effects on some CVD risk factors, the most important of which was a significant decrease in plasma LDL-cholesterol concentrations.
Viscous soluble dietary fiber has been demonstrated to reduce postprandial glycemia and may promote satiety. PolyGlycopleX (PGX) is a highly viscous polysaccharide manufactured by reacting glucomannan with other soluble polysaccharides using a proprietary process (EnviroSimplex). The resulting polysaccharide (alpha-D-glucurono-alpha-D-manno-beta-D-manno-beta-D-glucan, alpha-L-gulurono-beta-D-mannuronan, beta-D-gluco-beta-D-mannan, alpha-D-glucurono-alpha-D-manno-beta-D-manno-beta-D-gluco, alpha-L-gulurono-beta-D-mannurono, beta-D-gluco-beta-D-mannan) is a novel entity with the highest viscosity and water-holding capacity of currently known fibers.
MATERIALS AND METHODS:
A total of 29 sedentary overweight or obese adults (23 women; six men), ages 20-65 with a body mass index (BMI) range of 25 kg/m(2) to 36 kg/m(2) participated in a clinical weight-loss program. PGX (5 g) was consumed with 500 mL water, 5-10 minutes before each meal, 2-3 times daily for 14 weeks.
Significant reductions were observed (p less than 0.05) in weight (-5.79 +/- 3.55 kg), waist circumference (-12.07 +/- 5.56 cm), and percentage body fat (-2.43 +/- 2.39 percent) compared to baseline values. In addition, subjects employing PGX had a significant reduction of 19.26 percent (n=17; p less than 0.05) and 25.51 percent (n=16; p less than 0.05) in total and LDL plasma cholesterol values, respectively, at the end of the study period.
The consumption of PGX in concert with lifestyle modifications may be a useful strategy for weight loss in overweight and obese individuals.
Restricţia calorică (CR) fără malnutriţie creşte longevitatea şi întârzie declanşarea afecţiunilor asociate îmbătrânirii, la speciile cu durată scurtă de viaţă, începând cu organismele unicelulare şi până la şoarecii şi şobolanii de laborator. Valoarea lui CR ca instrument pentru a înţelege îmbătrânirea constă în faptul că pot fi translatate la oameni efectele pe care CR le are la primate. Aici noi arătăm că CR îmbunătăţeşte semnificativ supravieţuirea la maimuţe, atât legat de îmbătrânire cât şi de toate celelalte cauze de mortalitate, prin dietă restrictivă de aprox 30%, pe termen lung, începută din etapa de tânăr adult. Aceste date sunt în contradicţie cu observaţiile din raportul studiului intern al NIA din 2012, unde nu s-a detectat nici o diferenţă în ceea ce priveşte rata de supravieţuire între maimuţele hrănite normal pentru control şi cele cu CR. O comparaţie a greutăţii corporale la grupurile de control din ambele studii, pusă faţă în faţă cu datele colectate într-o bază de date aflată în relaţie cu mai multe centre, referitoare la îmbătrânirea primatelor, sugerează că maimuţele din grupa de control a NIA erau de fapt sub incidenţa CR. Datele noastre indicând beneficiile CR asupra îmbătrânirii la primate se păstrează.