Researchers also observed improvements in the gut microbiota composition, suggesting that the protein supplements may modulate the bacterial community.
“Based on the beneficial effects found to correlate with these two plant-based beverages, they could be considered as complementary management alternatives for overweight and obesity in male adolescent populations,” the researchers wrote in the journal Nutrients, noting that female studies are needed to clarify if effects are similar in both sexes.
“This study also highlights the relevance of supplementing diets with functional beverages that positively impact health, especially in anthropometric, biochemical, metabolic, and intestinal health indicators,” they added.
Benefits of soy and lupin protein
Soy and lupin are legumes included in functional foods for their high protein content and beneficial bioactive compounds.
Soy’s benefits may include protective effects against cardiovascular disease, hypertension, cancer, diabetes, and obesity. Fermented soy products such as tempeh may also help to regulate hunger and satiety hormones, helping to manage weight.
Lupin’s bioactive compounds exert anti-inflammatory and antioxidant effects, and this functional ingredient may also help to regulate blood sugar and lipid metabolism, making it useful for diabetes and obesity.
Both legumes promote the abundance of beneficial bacteria in the gut while helping to suppress unbeneficial species. Because the diversity of gut bacteria has been linked to obesity, this makes them ideal candidates for inclusion in interventions to manage metabolic disorders.
Study details
Researchers randomly assigned 30 Mexican male adolescents with overweight or obesity to consume a functional beverage providing a daily 10 g portion of either soy or lupin protein for 5 weeks. Evaluation showed that both groups had similar energy intake, macronutrients, and daily activity levels.
Before and after the intervention, the researchers made anthropometric measurements and analyzed adipocytokines, hormones, and the gut microbiome.
The results showed that both groups “exhibited significantly attenuated fasting glucose” and improved insulin sensitivity as measured by the HOMA2 index. Analysis of these changes suggested an improved metabolic efficiency “characterized by a potential reduction in insulin demand and restored insulin-mediated suppression of glucagon secretion,” wrote the researchers.
In addition, both groups had decreased levels of plasminogen activator inhibitor-1 (PAI-1), which is a key protein that regulates blood clotting, and visfatin, a fat-derived hormone linked to obesity and inflammation. The study noted that these improvements, coupled with enhanced insulin sensitivity, “suggest a healthier adipose tissue metabolic status,” which needs to be confirmed in further studies.
Glucose-dependent insulinotropic polypeptide (GIP), a hormone that stimulates insulin secretion, was decreased in the lupin group following treatment. The researchers also observed reduced levels of ghrelin, the hormone that signals hunger, in the lupin group, whereas the soy group showed no change.
The soy group showed a marked reduction in total cholesterol and triglycerides, which decreased by 10.4% and 17.1%, respectively.
With regard to the gut microbiome, the researchers observed: “the administration of soy and lupin protein beverages improved the relative abundance of the 16S rDNA gene, particularly in the LB [lupin] group, suggesting an enhancement in microbial richness.”
The study noted that microbiome changes may be linked to increases in butyrate-producing bacteria, which are associated with weight management.
The researchers acknowledged the study’s limitations, including the absence of a control group and a male-only cohort, and called for further studies to confirm their findings.
Source: Nutrients; doi: 10.3390/nu18132049; “Functional Soy and Lupin Protein-Based Beverages Modulate Gut Microbiome and Attenuate Metabolic Dysregulation in Adolescent Boys with Overweight and Obesity.” Authors: T. J. Guzman et al.
