Conducted by researchers at the University of Murcia (UCAM) and the Biomedical Research Institute of Murcia, Spain, the research advances understanding of the effects of the carob extract, beyond previous studies only conducted in animal models or healthy subjects.
Planttech’s LVLD extract is standardized for naturally occurring inositols from carob pods, including D-pinitol, myo-inositol and D-chiro-inositol.
The clinically relevant effects result from the synergistic interaction between D-pinitol and the wider spectrum of naturally occurring carob bioactives within the syrup matrix, according to Ignacio Zauldua, Planttech CEO, including polyphenols and micronutrient cofactors creating an “entourage effect”.
“Published data and the bibliography on d-pinitol is strong and we were encouraged by an earlier pilot study, but seeing statistically significant improvements in HbA1c, glucose metabolism and insulin sensitivity in prediabetics exceeded our expectations,” said Zauldua. “These clinically relevant effects in a randomized controlled human trial population at risk of progression to type 2 diabetes is a major breakthrough; we are very excited.”
The study was published in Nutrients and presented at the Planttech Symposium during Vitafoods Europe (May 5–7), where metabolic health was a clear theme across the show floor.
“Consumers are becoming much more aware of glucose management and postprandial response, particularly through wearable glucose monitors and broader metabolic health tracking,” Zauldua said. “We are seeing growing interest from companies looking for evidence-backed ingredients that can support healthier glucose metabolism in everyday nutritional formats.”
Diabetes disease prevention
Prediabetes is characterized by elevated blood glucose levels above the normal range. Subjects with prediabetes have a high risk of progressing to Type 2 diabetes mellitus (T2DM), a chronic metabolic disorder characterized by insulin resistance and progressive β-cell dysfunction, affecting over 463 million individuals worldwide.
The therapeutic potential of medicinal plants to relieve insulin resistance has been a matter of increasing interest due to their naturally high content of alkaloids, glycosides, terpenoids, flavonoids, gallotannins and other polyphenols which exert hypoglycemic activity and antioxidant effects.
The study
The 90-day randomized double-blind placebo-controlled human trial was conducted at the Health Sciences Department of Universidad Católica San Antonio de Murcia (UCAM). The participant population included 52 subjects (25 in the experimental group, 27 in the placebo group), including 27 men and 25 women, with a mean age of 45.6 ± 13.9 years.
Subjects were randomized to receive the carob extract or a placebo. The daily dose was 6.66 g, divided into two doses of 3.33 g each. The product was provided in sachets, to be diluted in 100 mL of water or juice and consumed 30 minutes before lunch and dinner for 90 consecutive days.
The study involved three assessment days —at baseline, day 45 and day 90. Venous blood samples were taken after 12 h fasting for assessment of glycemic profile, Oral Glucose Tolerance Test (OGTT), insulin resistance and sensitivity indexes, and lipid profile, as well as standard hematological and biochemical chemistry analyses. Fasting and postprandial capillary blood samples were collected, anthropometric variables were measured. Participants filled out a nutritional diary throughout the trial.
Resulting data indicated subjects who consumed the active product showed improvements in HbA1c (glycated hemoglobin) and glucose levels as compared with placebo.
Fasting serum insulin results indictaed within-group significant decreases in the experimental group, with insulin indexes improving significantly in the experimental group only. In the OGTT, there were significant improvements in the area under the curve (AUC) of glucose and insulin, as well as glucose peak, in the experimental group only.
The product was well tolerated and no adverse effects were recorded.
The researchers noted the limitations of the study include the single-center design, reduced sample size, and the short intervention period of 90 days.
Mechanism of action
Discussing the ingredient’s mechanism of action, the report notes an aqueous extract of carob leaves has previously been shown to reduce glucose absorption in vivo and in vitro in a dose-dependent manner. Also, a methanolic extract of carob pods showed inhibitory effects against amylase and glucosidase in a streptozotocin-nicotinamide-induced diabetic rat model.
Other experimental studies have further confirmed various carob-derived products can effectively inhibit key enzymes involved in carbohydrate digestion.
“Immature carob has been shown to reduce intestinal glucose absorption by interfering with sodium-dependent transport, thereby contributing to improvement of glycemic control,” the recent research states, adding that the insulin regulation effect of carob has been associated with its high content of D-pinitol, an inositol compound with insulin-mimetic and insulin-sensitizing mechanisms.
Zauldua said the team plans to expand its clinical program with larger and longer-duration studies, including additional work in prediabetic and metabolically challenged populations.
“We are also interested in exploring the role of the wider carob bioactive matrix and the ‘entourage effect’ in supporting glucose regulation and insulin sensitivity,” he added.
Source: Nutrients; doi: 10.3390/nu18101521; “Effects of Specific Carob (Ceratonia siliqua L.) Liquid Concentrate on Glucose Metabolism in Subjects with Prediabetes: A Randomized Double-Blind Controlled Clinical Trial", Authors: Pérez-Piñero, S. et al.
