How Raspberry Leaf Tea Reduces Insulin Surges From Table Sugar

Researchers recovered that raspberry leafage beverage importantly reduced early postprandial glucose and insulin spikes erstwhile consumed pinch sucrose, but not glucose, successful patient adults. The effect is linked to ellagic acid–rich polyphenols that inhibit carbohydrate-digesting enzymes.

Study: Effects of Raspberry Leaf Tea Polyphenols connected Postprandial Glucose and Insulin Responses successful Healthy Adults. Image Credit: Evgrafova Svetlana / Shutterstock

In a caller study published successful nan Nutrients journal, researchers tested a 10 g raspberry leafage beverage infusion alongside 50 g of oral carbohydrate loads to analyse early postprandial glucose and insulin responses successful patient adults.

They recovered that nan beverage importantly lowered humor glucose astatine 15 and 30 minutes (−1.19 mmol/L and −2.03 mmol/L, representing 25.6% and 43.6% reductions) and insulin astatine 15 (−113.9 pmol/L), 30 (−161.8 pmol/L), and 60 minutes (−139.4 pmol/L) erstwhile co-ingested pinch sucrose, pinch nary effect erstwhile co-ingested pinch glucose. This effect is plausibly mediated by ellagic acid–rich polyphenols inhibiting α-glucosidase and β-fructofuranosidase (sucrase), delaying sucrose hydrolysis.

Background

Type 2 glucosuria mellitus (T2DM) is simply a awesome and increasing world wellness issue, pinch prevalence doubling from 1990 to 2022, now affecting much than 800 cardinal group worldwide.

The information results from inadequate insulin accumulation aliases impaired insulin action. This leads to chronic hyperglycemia and complications specified arsenic cardiovascular disease, neuropathy, kidney damage, and nan request for amputations.

While medications exist, safer and much affordable alternatives are progressively sought to support humor sweetener control.

Polyphenols are people occurring compounds recovered successful wines, vegetables, fruits, and teas. They person shown committedness successful improving glucose metabolism. These compounds enactment arsenic antioxidants, trim inflammation, heighten insulin sensitivity, and slow carbohydrate digestion. In turn, they blunt humor sweetener spikes.

Raspberry leaves, which person agelong been utilized successful herbal medicine, are rich | successful bioactive compounds specified arsenic phenolic acids, ellagitannins, and flavonoids.

Despite their nutritional potential, astir investigation has focused connected nan raspberry, not nan fruit. There are only constricted studies connected raspberry leaves. Previous analyses identified ellagic acerb and quercetin derivatives arsenic ascendant successful raspberry leaves. These compounds person beardown antidiabetic and antioxidant properties.

About nan study

Anecdotal grounds that raspberry leafage beverage lowers glucose for group pinch gestational glucosuria led researchers to analyse whether it tin likewise trim postprandial insulin and glucose responses utilizing a randomized crossover trial.

They recruited 22 patient individuals betwixt nan ages of 18 and 65, pinch a assemblage wide scale (BMI) ranging from 18 to 34.9 kg/m². Eligible participants exhibited normal fasting glucose levels and nary history of caller antibiotic use, chronic illness, aliases diabetes. They did not smoke, return supplements aliases medications that could impact their metabolism, aliases portion intoxicant to excess. Pregnant individuals and those pinch nutrient allergies were excluded.

The participants attended 4 trial sessions, pinch 2 to four-week washout periods successful between. The 4 interventions were 50 g of glucose, glucose and 10 g of raspberry leafage tea, 50 g of sucrose, aliases sucrose and raspberry leafage tea. The beverage was brewed for 5 minutes; each serving contained astir 50 mg of full polyphenols, predominantly ellagitannins and ellagic acid.

Blood samples were collected astatine baseline and aft 15, 30, 60, 90, and 120 minutes post-consumption. Glucose was analyzed utilizing nan hexokinase method, and insulin via automated immunoassay, pinch strict value power procedures. Statistical analyses employed study of variance (ANOVA) pinch station hoc tests and independent t-tests.

Key findings

Chemical study confirmed that raspberry leafage beverage is rich | successful polyphenols, pinch ellagic acerb being nan ascendant compound. A five-minute infusion yielded nan highest polyphenol content, supporting its usage arsenic nan standardized mentation successful this trial.

Of nan 22 who enrolled, 20 completed each study visits. Participants were patient adults pinch comparable baseline glucose levels crossed each trial conditions.

When sucrose was consumed, nan beverage importantly reduced early postprandial glucose and insulin responses compared to sucrose alone. With sucrose, mean glucose fell by 1.19 mmol/L astatine 15 minutes and 2.03 mmol/L astatine 30 minutes (p = 0.001 and p = 0.0004, respectively). Insulin levels were suppressed by 113.9 pmol/L astatine 15 minutes (p = 0.019), 161.8 pmol/L astatine 30 minutes (p = 0.0008), and 139.4 pmol/L astatine 60 minutes (p = 0.025). These effects propose a moderating domiciled of raspberry leafage beverage successful attenuating sucrose-induced hyperglycemia and hyperinsulinemia.

In contrast, erstwhile glucose was consumed, nary statistically important differences successful humor glucose aliases insulin were observed betwixt beverage and power conditions. Both glucose and insulin peaked astatine 30 minutes earlier returning to baseline by 120 minutes, sloppy of beverage intake.

This confirms that nan beneficial effects of nan beverage are exclusive to disaccharide metabolism, peculiarly targeting sucrose digestion alternatively than monosaccharide absorption.

Conclusions

This proceedings is nan first to show that raspberry leafage beverage reduces postprandial glucose and insulin levels pursuing sucrose intake, but not glucose intake, successful patient adults. The effect whitethorn beryllium owed to nan beverage inhibiting nan activity of enzymes that break down carbohydrates, specified arsenic α-glucosidase and sucrase, chiefly done ellagic acerb and different polyphenols.

Importantly, nan beverage did not nutrient gastrointestinal broadside effects often seen pinch pharmaceutical enzyme inhibitors, suggesting it whitethorn connection a well-tolerated dietary strategy for moderating glycemic responses.

Strengths see nan randomized crossover creation and nan usage of venous humor sampling, which provides meticulous metabolic measurements.

However, limitations see nan acute (single-dose) design, nan deficiency of blinding and placebo control, nan mini and homogeneous sample size, nan short duration, and nan attraction connected only 2 carbohydrate sources. These factors restrict generalizability and forestall conclusions astir semipermanent effects.

In conclusion, raspberry leafage beverage shows committedness arsenic a earthy modulator of postprandial glycemia. Larger, longer-term studies successful divers populations, including those pinch impaired glucose control, are warranted.