Elderberry juice promotes fat burning and intestinal health in overweight adults

New research shows that consuming elderberry juice significantly improves fat oxidation, glucose levels and gut microbiota after just one week, making it a promising dietary supplement for treating obesity in overweight adults.

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A study published in the journal Nutrients highlights the effectiveness of anthocyanin-rich elderberry juice in improving gut health and combating obesity in overweight or obese adults.

background

Obesity is a multifactorial disease associated with a number of cardiometabolic complications. The prevalence of obesity is estimated at 42% in the United States, with a projected increase of 48-55% by 2050.

Healthy eating habits such as the Mediterranean diet play an important role in alleviating cardiometabolic complications associated with obesity. This type of diet contains larger amounts of fruits and vegetables that are rich in various bioactive compounds, including polyphenols and flavonoids.

Anthocyanins are a subclass of flavonoids with known health benefits against obesity-related diseases, including diabetes, dyslipidemia and cardiovascular disease. There is evidence that anthocyanins have health benefits by preventing intestinal absorption of monosaccharides, increasing fat and muscle cell metabolism, and modulating the composition of the intestinal microbiota.

Elderberry juice contains particularly high amounts of cyanidin-based anthocyanins. Scientists in the current study have previously shown that rodents fed a diet containing 45% fat and 10% elderberry juice powder showed physical and metabolic improvements, caused in part by changes in gut microbiota caused by elderberry juice.

In a randomized, placebo-controlled, crossover clinical trial, scientists examined the effects of anthocyanin-rich elderberry juice on glucose tolerance, fat oxidation, and gut microbiota in healthy, obese adults.

Study design

The study was conducted on 18 overweight adults who were randomly divided into the intervention group and the control group. All participants underwent two one-week study intervention periods separated by a three-week washout period.

In the intervention group, participants received 100% elderberry juice twice daily for one week. In the control group, participants received a placebo drink that matched the taste and color every day for one week.

In the second one-week intervention period, which began after the washout period, the groups alternated study interventions (elderberry juice and placebo drink).

Each intervention period included four days of controlled feeding with a 40% fat diet to facilitate comparison of study parameters between the two study groups. This crossover design allowed participants to serve as their own control, increasing the robustness of the results.

Important observations

A total of 18 participants completed the study protocol. Evaluation of the self-reported questionnaires showed 100 percent adherence to test drink consumption. None of the participants reported gastrointestinal distress or inability to consume the prescribed foods and test drinks.

Indirect colorimetric measurements of carbohydrates, fat, respiratory quotient (CO2 produced/O2 consumed) and energy expenditure revealed that consumption of elderberry juice resulted in a significant reduction in respiratory quotient compared to placebo.

This corresponded to a significant induction of fat oxidation and a reduction of carbohydrate oxidation in the elderberry juice group. Of note, although fat oxidation increased during the 30-minute treadmill run, the difference was only marginally significant (p = 0.071), meaning further research is needed to confirm this finding. No significant difference was found between the groups with regard to energy consumption.

Elderberry juice consumption also significantly reduced respiratory quotient during moderate physical activity, suggesting increased fat oxidation even outside of meals.

Regarding glucose tolerance, the study found that challenging a meal with elderberry juice was associated with a significant reduction in blood sugar levels and a moderate reduction in blood insulin levels.

Profiling the gut microbiota

The study found that elderberry juice intake significantly increased the abundance of Firmicutes and Actinobacteria and decreased the abundance of Bacteroidetes at the phylum level.

At the genus level, elderberry juice intake increased Faecalibacterium, Ruminococcaceae, and Bifidobacterium and decreased Bacteroides and lactic acid-producing bacteria. These observations suggest a positive influence of elderberry juice on gut microbiota profiles. However, these changes were subtle and did not indicate profound changes in the microbiota.

Study Importance

The study shows positive effects of elderberry juice on blood sugar tolerance, fat oxidation and gut microbiota profile.

The study protocol includes 355 grams of elderberry juice daily, which is equivalent to more than 720 milligrams of cyanidin-based anthocyanins. With this regimen, the study found a 24% reduction in the blood sugar response curve, a 9% reduction in the insulin response curve, and a 27% increase in fat oxidation.

Regarding the gut microbiota profile, the study finds slight improvements in microbial communities with health benefits after consuming elderberry juice.

Taken together, these observations suggest that consuming elderberry juice for one week can effectively support the management of obesity in healthy adults with a body mass index (BMI) greater than 25 kg/m2.

However, the study has limitations. Due to the one-week treatment period, no long-term safety profile or health benefits associated with consumption of elderberry juice could be achieved.

Two challenge meals used in the study had a 15-gram difference in total sugar content. Given this limitation, scientists suggest that the observed improvement in glucose tolerance and insulin sensitivity, while promising, needs to be confirmed by additional testing that places greater control on meal challenge design, including macronutrients and energy balance between meals .

The scientists also emphasize the need for future studies to investigate the mechanisms of action of elderberry juice using longer-term clinical trials and preclinical and translational research models.