Very Low Calorie Diet (VLCD) is a stringent caloric restriction regimen used in the short-term management of obese patients, which can effectively reduce body weight and blood glucose levels. This prospective study aimed to evaluate the short-term impacts of a VLCD on body composition, metabolic parameters, and oral microbiota in obese adults, exploring its therapeutic potential for metabolic dysfunction and inflammation-related comorbidities. This prospective study was conducted on the basis of a cohort of overweight/obese individuals at Affiliated Hospital of Hubei University of Chinese Medicine. Patient eligibility for inclusion in this study was determined by the adoption of a complete short-term VLCD therapy following their entry into the cohort. The study aimed to explore the improvements in body composition, blood glucose, blood lipids, and inflammatory markers post-VLCD intervention, as well as the safety of the treatment. Additionally, it analyzed the changes in the microbiota of the upper gastrointestinal tract, specifically the oral coating. The study was concluded on December 31, 2023. In the per-protocol cohort ( n = 101), the VLCD intervention induced rapid, clinically meaningful reductions in body weight, body fat mass(BFM), body mass index (BMI), and visceral fat area(VFA). Skeletal muscle mass(SMM) decreased modestly. Metabolic parameters improved significantly, with decreases in fasting blood glucose (FBG), fasting insulin (FIns), and homeostasis model assessment of insulin resistance (HOMA-IR). Lipid profiles showed transient increases in low-density lipoprotein cholesterol (LDL-C) and total cholesterol (CHOL) at day 5, normalizing by two-week follow-up, alongside reduced triglycerides (TG). Systemic inflammation markers declined after resuming normal diet, including alanine aminotransferase (ALT) and high-sensitivity C-reactive protein (hs-CRP); uric acid (UA) peaked transiently during the VLCD before falling below baseline. Tongue-coating microbiota exhibited increased Shannon diversity and shifted community structure, with 12 reduced species associated with 19 systemic diseases. The VLCD intervention shows significant short-term benefits in weight loss and body fat reduction. Furthermore, it shows potential for reducing the risk of chronic diseases by modulating systemic inflammation and altering the oral microbiome. Further studies are warranted to assess long-term efficacy and sustainability. Chinese Clinical Trail Registry (No. ChiCTR2200063126, date of registration: 31 August 2022), https://www.chictr.org.cn/hvshowproject.html?id=188695&v=1.2 .
Zhu et al. (Mon,) studied this question.