Effect of Mori ramulus on the postprandial blood glucose levels and inflammatory responses of healthy subjects subjected to an oral high-fat/sucrose challenge: A double-blind, randomized, crossover clinical trial

Abstract Background The antidiabetic and hypoglycemic effects of chitosan have been reported in previous studies. We have previously shown that chitosan oligosaccharide reduces postprandial blood glucose levels in vivo. We conducted a short-term crossover study to support the results of the previous study. Methods The study was a randomized, double-blind, controlled crossover trial completed at one clinical research site. Subjects with impaired glucose tolerance and impaired fasting glucose and healthy subjects were randomly assigned to consume one of two different experimental test capsules that differed in only the sample source (GO2KA1 vs placebo), and all subjects were instructed to consume the 75 g sucrose within 15 min. After a 7-day interval, the subjects consumed the other capsules that were not consumed on the first day. We assessed blood glucose levels using a 2-h oral sucrose tolerance test. The study was registered at clinicaltrials.gov (NCT03650023). Results The test group showed significantly lower blood glucose levels at 60 min (p = 0.010) and postprandial blood glucose areas under the curve (p = 0.012). The change in blood glucose levels at 60 min was significantly lower in the test group than in the placebo group (p = 0.017). Conclusions Based on the results of this study, the consumption of chitosan oligosaccharide (GO2KA1) supplements with a meal can effectively reduce postprandial blood glucose levels, which is relevant to the prevention of diabetes.

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Impact of insufficient sleep on dysregulated blood glucose control under standardised meal conditions

Diabetologia ◽

10.1007/s00125-021-05608-y ◽

2021 ◽

Author(s):

Neli Tsereteli ◽

Raphael Vallat ◽

Juan Fernandez-Tajes ◽

Linda M. Delahanty ◽

Jose M. Ordovas ◽

...

Keyword(s):

Blood Glucose ◽

Glycaemic Control ◽

Sleep Efficiency ◽

Postprandial Blood Glucose ◽

Poor Sleep ◽

High Fat ◽

Sleep Period ◽

Glucose Levels ◽

High Carbohydrate ◽

Blood Glucose Levels

Abstract Aims/hypothesis Sleep, diet and exercise are fundamental to metabolic homeostasis. In this secondary analysis of a repeated measures, nutritional intervention study, we tested whether an individual’s sleep quality, duration and timing impact glycaemic response to a breakfast meal the following morning. Methods Healthy adults’ data (N = 953 [41% twins]) were analysed from the PREDICT dietary intervention trial. Participants consumed isoenergetic standardised meals over 2 weeks in the clinic and at home. Actigraphy was used to assess sleep variables (duration, efficiency, timing) and continuous glucose monitors were used to measure glycaemic variation (>8000 meals). Results Sleep variables were significantly associated with postprandial glycaemic control (2 h incremental AUC), at both between- and within-person levels. Sleep period time interacted with meal type, with a smaller effect of poor sleep on postprandial blood glucose levels when high-carbohydrate (low fat/protein) (pinteraction = 0.02) and high-fat (pinteraction = 0.03) breakfasts were consumed compared with a reference 75 g OGTT. Within-person sleep period time had a similar interaction (high carbohydrate: pinteraction = 0.001, high fat: pinteraction = 0.02). Within- and between-person sleep efficiency were significantly associated with lower postprandial blood glucose levels irrespective of meal type (both p < 0.03). Later sleep midpoint (time deviation from midnight) was found to be significantly associated with higher postprandial glucose, in both between-person and within-person comparisons (p = 0.035 and p = 0.051, respectively). Conclusions/interpretation Poor sleep efficiency and later bedtime routines are associated with more pronounced postprandial glycaemic responses to breakfast the following morning. A person’s deviation from their usual sleep pattern was also associated with poorer postprandial glycaemic control. These findings underscore sleep as a modifiable, non-pharmacological therapeutic target for the optimal regulation of human metabolic health. Trial registrationClinicalTrials.gov NCT03479866. Graphical abstract

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Black tea decreases postprandial blood glucose levels in healthy humans and contains high-molecular-weight polyphenols that inhibit α-glucosidase and α-amylase in vitro: a randomized, double blind, placebo-controlled, crossover trial

Functional Foods in Health and Disease ◽

10.31989/ffhd.v11i5.791 ◽

2021 ◽

Vol 11 (5) ◽

pp. 222

Author(s):

Yoshikazu Isono ◽

Hisako Watanabe ◽

Masafumi Kumada ◽

Tsuyoshi Takara ◽

Shin-ichiro Iio

Keyword(s):

Molecular Weight ◽

Blood Glucose ◽

High Molecular Weight ◽

Area Under The Curve ◽

Black Tea ◽

Postprandial Blood Glucose ◽

Double Blind ◽

Glucose Levels ◽

Healthy Humans ◽

Blood Glucose Levels

Background: To prevent diabetes, it is important to control postprandial glycemic levels. Studies have suggested that consuming black tea decreases the risk of type 2 diabetes; however, only a few studies have examined the effects of black tea on postprandial glycemic control after consuming starch-rich foods. In addition, the mechanism underlying the suppression of postprandial glucose levels remains unclear.Objective: To investigate the effects of black tea on postprandial blood glucose levels in healthy humans and to identify the components of black tea that inhibit digestive enzymes.Methods: The inhibitory activity of black tea on digestive enzymes was measured, and the inhibitory components were fractionated. Healthy Japanese adults ingested 200 ml of black tea, and its effect on postprandial blood glucose and insulin levels were investigated. Results: Black tea dose-dependently inhibited α-glucosidase, sucrase, and α-amylase activity. The major components responsible for this inhibition were high–molecular-weight polyphenols. The galloyl moieties present in these compounds play an important role in their inhibitory activities. Two randomized, double-blind, placebo-controlled, crossover studies of healthy human subjects (total n = 46) were conducted to investigate the effect of black tea on blood glucose and insulin levels. Combined data from the two studies showed that black tea ingestion (200 mL) after cooked rice intake (200 g) significantly reduced the incremental area under the curve of glucose (P =.024) and insulin (P =.014) compared to placebo drink.Conclusions: The high–molecular-weight polyphenols in black tea inhibited α-glucosidase, sucrase, and α-amylase activity in a dose-dependent manner. Furthermore, black tea ingestion after eating cooked rice significantly reduced the incremental area under the curve of glucose and insulin. These effects of black tea could be attributed to the inhibition of digestive enzymes by high–molecular-weight polyphenols containing galloyl groups.Keywords: black tea, blood glucose, α-glucosidase, α-amylase, polyphenol

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Single-Dose Pinitol Ingestion Suppresses Post-Prandial Glucose Levels: A Randomized, Double-Blind, Placebo-Controlled, Crossover Trial

Natural Product Communications ◽

10.1177/1934578x19890816 ◽

2019 ◽

Vol 14 (12) ◽

pp. 1934578X1989081

Author(s):

Yoshio Suzuki ◽

Keishoku Sakuraba ◽

Takuya Wada ◽

Naoya Watabane ◽

Seijiro Wada ◽

...

Keyword(s):

Type 2 Diabetes ◽

Single Dose ◽

Blood Glucose ◽

Crossover Trial ◽

Postprandial Blood Glucose ◽

Double Blind ◽

Double Blind Placebo ◽

Glucose Levels ◽

Blood Glucose Levels

Limited studies have demonstrated that chronic consumption of pinitol improved glucose tolerance, and single-dose ingestion (0.6 g) 60 minutes prior to meals suppressed postprandial glucose levels in patients with type 2 diabetes mellitus. However, higher doses (6 g) were required in healthy people who ingested pinitol with a meal. This randomized, double-blind, placebo-controlled, crossover trial was conducted to clarify the effect of 0.6 g of pinitol with a meal on postprandial blood glucose levels in healthy adults. Twenty volunteers aged 18 to 25 years participated in this study. Participants visited the laboratory after an overnight fast. After measuring fasting blood glucose levels (FBG), they consumed test food (0.6 g of pinitol or placebo) and then ate breakfast (577 kcal; protein 14.0 g; fat 5.6 g; and carbohydrate 117.7 g). Blood glucose levels were measured immediately after eating and at 30, 60, 90, and 120 minutes after breakfast. Participants’ mean FBG level was 102.6 ± 8.2 mg/dL. Participants were categorized by their FBG as normal ( n = 5; ≤99 mg/dL) or impaired glucose tolerance (IGT) ( n = 15; 100-125 mg/dL). The incremental area under the curve of blood glucose over 120 minutes after the meal was significantly suppressed by pinitol in the IGT group ( P < 0.05), but not in the normal group. Therefore, pinitol was considered to maintain postprandial blood glucose levels in healthy people with IGT, and may contribute to the prevention of type 2 diabetes.

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