Reduction in postprandial glucose excursion and prolongation of satiety: possible explanation of the long-term effects of whole grain salba (salvia hispanica l.)

European Journal of Clinical Nutrition (2010), 1–3& 2010 Macmillan Publishers Limited All rights reserved 0954-3007/10 $32.00 Reduction in postprandial glucose excursion andprolongation of satiety: possible explanation ofthe long-term effects of whole grain Salba(Salvia Hispanica L.) V Vuksan1,2,3,4,5, AL Jenkins1, AG Dias1,3, AS Lee1,3, E Jovanovski1, AL Rogovik1 and A Hanna4,5 1Clinical Nutrition and Risk Factor Modification Centre, St Michael’s Hospital, Toronto, Ontario, Canada; 2Keenan Research Center ofthe Li Ka Shing Knowledge Institute, St Michael’s Hospital, Toronto, Ontario, Canada; 3Department of Nutritional Sciences, Faculty ofMedicine, University of Toronto, Toronto, Ontario, Canada; 4Department of Medicine, Faculty of Medicine, University of Toronto,Toronto, Ontario, Canada and 5Division of Endocrinology and Metabolism, St Michael’s Hospital, Toronto, Ontario, Canada Despite strong correlations linking whole-grain consumption to reductions in heart disease, the physiological mechanismsinvolved remain ambiguous. We assessed whether Salba (Salvia Hispanica L.) whole grain reduces postprandial glycemia inhealthy subjects, as a possible explanation for its cardioprotective effects observed in individuals with diabetes. The study usedacute, randomized, double-blind, controlled design in which 11 healthy individuals (6 males and 5 females; body mass index22.3±2.8 kg/m2) received 0, 7, 15 or 24 g of Salba baked into white bread. Capillary samples and appetite ratings werecollected over 2 h after consumption. A dose-response reduction in postprandial glycemia (P ¼ 0.002, r2 ¼ 0.203) was observedwith all three doses of Salba, significantly decreasing incremental areas under the curve (iAUCs) and time point-specific bloodglucose (Po0.05). Appetite ratings were decreased at 60 min after high, 90 min after high and intermediate and at 120 min afterall treatments (Po0.05). Decrease in postprandial glycemia provides a potential explanation for improvements in bloodpressure, coagulation and inflammatory markers previously observed after 12-week Salba supplementation in type II diabetes.
European Journal of Clinical Nutrition advance online publication, 20 January 2010; Keywords: Salba; whole grain; glycemia; appetite glycemia. To analyze this hypothesis we studied the acuteeffect of escalating doses of Salba on glycemia and satiety.
Given the importance of consuming whole grains as acardioprotective measure, there is increasing interest in theireffects on type II diabetes. We have previously shown thatconsumption of 37 g/day of the oily grain Salvia Hispanica L.
(Salba) improves cardiovascular risk factors by reducingblood pressure, inflammatory and coagulation markers in A total of 11 healthy individuals (6 males and 5 females; age subjects with well-controlled type II diabetes 30±3.6 years; body mass index 22.2±1.3 kg/m2) partici- Mechanistically, this may occur through Salba’s pated in this study. Subjects with gastrointestinal/metabolic ability to trigger a favorable biochemical cascade that leads diseases or who were taking potential postprandial meta- to the observed changes through reductions in postprandial bolism-altering supplements were excluded. The study wasapproved by the research ethics board of St Michael’sHospital. Written informed consent was obtained from all Correspondence: Dr V Vuksan, Clinical Nutrition and Risk Factor Modification Centre, St Michael’s Hospital, 70 Richmond Street East, Suite 100, Toronto, A double-blind, placebo-controlled, randomized, crossover design was used. Participants attended the clinic on five E-mail: Received 28 July 2009; revised 24 October 2009; accepted 6 November 2009 mornings, separated by at least 48 h, after a 10- to 12-h fast.
Finger-prick capillary blood and subjective appetite ratings eat right now?). Appetite rating was calculated from these were collected in the fasting state and at 15, 30, 45, 60, 90 Salba is a brand name used to describe two registered white varieties, Sahi Alba 911 and 912, that are the result of selective breeding from the black grain Salvia Hispanica L.
Incremental areas under the curve (iAUCs) for blood (also popularly called Chia) by the Peruvian company glucose and for the average appetite ratings were calculated Agrisalba S.A. Salba has a nutrient profile that is approxi- mately 20% higher than generic or regular Chia. In addition, Statistical analysis was performed using NCSS-2000 the nutrient profile of Salba is highly standardized, which (NCSS, Kaysville, UT, USA). Results were expressed as allows for a high degree of reproducibility. Experimental mean±s.d. and significance was set at Po0.05. Statistical meals contained 50 g available carbohydrate with addition of analysis was conducted after a comparison of the sampling 0, 7, 15 or 24 g of Salba (Salba Smart Natural Products, distribution to a normal distribution (Shapiro–Wilk and Denver, CO, USA), which was ground by micro-slicing rather Kolmogorov–Smirnov tests). Pearson’s correlations and than the crushing method (to reduce rancidity) and baked linear regression analysis were used to determine dose- into white bread in a Black & Decker All-In-One Pro response relationships for glucose and appetite iAUCs.
Breadmaker (The Black & Decker Corporation, Towson, Two-way analysis of variance was performed with the MD, USA) according to standard recipes. Energy value and glucose values and appetite scores at each time point with macronutrient compositions of test and control breads are post hoc assessment using the Neuman–Keuls method to shown in Control white bread was consumed twice Capillary blood samples were analyzed using the glucose- oxidase method (YSI 2300 STAT Analyzer, Yellow Springs, OH, USA). Satiety was assessed using four questions withopposing statements at each end of 100 mm visual analog Compared with control, the percentage of reductions in scale (How full do you feel? How strong is your desire to eat? mean iAUCs for blood glucose were 41, 28 and 21% after How hungry do you feel? How much do you think you could high, intermediate and low Salba doses, respectively (Po0. 05;Furthermore, significantly lower blood glucoselevels were observed after the high dose at 30, 45 and 60 min, Energy value and macronutrient compositions of test and intermediate at 60 min and low dose at 45 min (Po0.05) compared with control. Linear regression analysis showed glucose iAUCs to be significantly associated with the Salba dose (P ¼ 0.002; r2 ¼ 0.203; r ¼ 0.45).
Appetite ratings were decreased when compared with control at 60, 90 and 120 min after the high dose, at 90 and 120 min after the intermediate and at 120 min after the low dose (Po0.05; Incremental AUC appetite ratings decreased by 63, 58 and 41% after high, intermediate and low doses but this did not reach significance. Significant Incremental changes and iAUCs for postprandial blood glucose and appetite after high, intermediate, and low dose, and control treatments Abbreviations: iAUC, incremental area under the curve; Int., intermediate.
aData are mean±s.d. IAUCs are expressed in min mol/l for blood glucose and in min mm for appetite.
bSignificantly different from the control group (Po0.05).
Salba reduces postprandial glycemiaV Vuksan et al correlation between incremental blood glucose and incre- mental appetite values was observed (Po0.001; r ¼ 0.32).
The authors declare no conflict of interest.
These preliminary data suggest that ingestion of escalatingdoses of Salba attenuate postprandial glycemia in a dose- Salba Smart Natural Products, Denver, CO, USA, provided dependent manner in healthy subjects. On average, each Salba grain. The results were presented as an abstract at gram of Salba baked in the white bread reduced postprandial glycemia by 2% compared with the control. Reductions in 2008;22:305.6), supported by an unrestricted travel grant postprandial glycemia observed after Salba are not dissimilar received from Salba Corporation S.A, Buenos Aires, Argentina.
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