Rondanelli M, Gasparri C, Perna S, et al. A 60-day green tea extract supplementation counteracts the dysfunction of adipose tissue in overweight post-menopausal and class I obese women. Nutrients. December 2022;14(24):5209. doi:10.3390/nu14245209.
Hormonal changes during menopause can cause an increase in adipose tissue. This increase can result in a greater risk of metabolic disorders such as cardiovascular diseases and type 2 diabetes. Dietary supplements in combination with a low-calorie diet can counteract the dysfunction of adipose tissue. Green tea (Camellia sinensis, Theaceae) supplementation can positively affect energy and hormone balance. Green tea contains catechins which have been shown to increase fat oxidation and have anti-obesity effects. In a meta-analysis, green tea improved lipid and glucose metabolism. The authors conducted a randomized, double-blind, placebo-controlled trial to evaluate the effects of a 60-day dietary supplementation with green tea extract on adipose tissue dysfunction in overweight or class I obese post-menopausal sedentary women.
This study was conducted at the Dietetic and Metabolic Unit of the Santa Margherita Institute, University of Pavia, Italy. Inclusion criteria included women who were post-menopausal, were overweight or class I obese, did not have any past cardiovascular disease, were free of overt liver, renal and thyroid disease, and were not taking medication that may affect glucose or lipid metabolism. Exclusion criteria included participants who smoked or drank more than two standard alcoholic beverages per day.
The trial product was a 150 mg capsule of Greenselect® Phytosome® (Indena S,p.A.; Milan, Italy) that contained ≥ 19.0% ≤ 25.0% catechins, ≥ 13.0% of epigallocatechin-3-O-gallate, and ≤ 0.1% of caffeine. These constituents were all verified using high-performance liquid chromatography. The placebo was provided by Indena and identical in appearance to the treatment capsule. Placebo ingredients were described as inactive food components. Participants ingested two doses of either placebo or treatment each day for 60 days. Patients underwent a consultation with a dietician and consumed a hypocaloric diet during the trial. A visual-analogue scale was used to evaluate the sense of hunger and satiety during the trial.
Blood samples, 24 h-urine samples, anthropometric measurements, body composition, visceral adipose tissue (VAT) volume, and respiratory exchange measurements were obtained at baseline, after 30 days, and after 60 days. Blood samples taken at baseline and after 60 days included glucose and lipid profiles, inflammatory markers, liver and kidney function, the hormonal status regarding satiety, and the status of circulating catecholamines. At 30 days, the glucose profile, the inflammatory state, and the state of circulating catecholamines was assessed. Adverse events were also recorded.
Twenty-eight women were recruited for the study resulting in a total of 14 participants in each group. The mean age in the placebo group was 56.92 ± 5.70 years, and the mean body mass index (BMI) was 31.10 ± 3.54 kg/m2. The mean age in the green tea group was 60.57 ± 7.28 years, and the mean BMI was 31.99 ± 2.23 kg/m2.
Compared to baseline, the green tea group saw a significant decrease in respiratory quotient (P < 0.0001), insulin (P = 0.007), homeostasis model assessment (P = 0.01), waist circumference (P < 0.0001), VAT (P = 0.0008), fat mass (P < 0.0001), percentage of carbohydrates, (P < 0.0001), and C-reactive protein (P = 0.007) and a significant increase in adiponectin (P = 0.02), noradrenalin (P = 0.001), resting energy expenditure (P = 0.006), percentage lipid oxidation (P < 0.0001), and adiponectin/leptin ratio (P = 0.0001). The placebo group saw a significant decrease in waist circumference (P = 0.02) and a statistically significant increase in the adiponectin/leptin ratio (P = 0.04) after 60 days. A significant change was seen between the supplemented and placebo groups for insulin (P = 0.009), homeostasis model assessment (P = 0.02), C-reactive protein (P = 0.02), waist circumference (P = 0.007), resting energy expenditure (P = 0.009), percentage of carbohydrates, (P = 0.0006), percentage lipid oxidation (P = 0.0006), and respiratory quotient (P = 0.009). The article does not state if there were adverse events reported by the participants.
The authors conclude green tea has significant benefits for lipolysis pathway in women that are post menopause. Green tea was shown to decrease weight and body fat markers. One strength of this study was that the authors analyzed a variety of factors that can determine weight loss and change in body composition. Limitations included not measuring urinary nitrogen excretion, not being able to calculate protein oxidation, using a specific population of overweight and obese individuals, and having a small number of participants. Further research with different populations of individuals and a larger number of participants is needed to verify these results.
Three of the article authors are employed by Indena. The remaining authors declare no conflict of interest.