An observational study in Obesity & Overweight and Obesity (Disorder), sponsored by University of Helsinki. Completed. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-03-06.
Sponsored by University of Helsinki · Observational
This prospective observational study investigates weight loss and metabolic changes in adults with obesity undergoing standard clinical diet-induced lifestyle treatment and counseling. Participants follow a very-low-calorie diet followed by a conventional weight loss diet in addition to lifestyle counseling and are followed for 12 months. The study examines weight loss as the primary outcome and characterizes changes in body composition, fat distribution, glucose metabolism, inflammation, and adipose tissue biology as secondary outcomes.
Obesity is associated with metabolic complications including insulin resistance, fatty liver disease, dyslipidaemia, and systemic inflammation. Weight loss can improve these complications, yet individuals vary widely in weight loss, fat distribution and metabolic response. Subcutaneous adipose tissue dysfunction, including impaired mitochondrial biogenesis and increased inflammation, is thought to play a central role.
This prospective observational study follows adults with obesity undergoing standard-of-care diet and lifestyle treatment at Helsinki University Central Hospital, Helsinki, Finland. The intervention consists of a very-low-calorie diet for approximately 10 weeks, followed by gradual transition to a conventional weight loss diet and multidisciplinary clinical follow-up.
Assessments are performed at baseline, 6 months, and 12 months and include anthropometry, body composition (BIA, DXA), fasting blood samples, and oral glucose tolerance testing. Subcutaneous adipose tissue biopsies are obtained from four anatomical depots (gluteal, abdominal, breast, and upper arm) for molecular, mitochondrial, epigenetic, and histological analyses.
The primary outcome is diet-induced weight loss over 12 months. Secondary outcomes include changes in fat distribution, insulin sensitivity, lipid profile, inflammation, mitochondrial measures in adipose tissue, and depot-specific adipose tissue characteristics.
6,296 studies on the registry are indexed under Obesity; 1,695 are open to participants now.
This study's enrollment of 22 is below the median of 135 across 1,283 observational studies indexed under Obesity.
Browse Obesity studies →University of Helsinki is the lead sponsor of 129 studies on the registry; 19 are open to participants now.
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Patients seeking treatment for obesity at Helsinki University Central Hospital and affiliated outpatient obesity clinics.
Exclusion Criteria:
Adults with obesity undergoing standard clinical diet treatment including a very-low-calorie diet followed by transition to a conventional weight loss diet and lifestyle counseling
Behavioral: Diet-Induced Weight Loss Program
Standard clinical obesity treatment consisting of a very-low-calorie diet for approximately 10 weeks followed by transition to a conventional weight loss diet with multidisciplinary clinical follow-up.
Percent Total Body Weight Loss (%TWL)
Percentage change in body weight from baseline, calculated as 100 × (baseline weight - follow-up weight) / baseline weight
Time frame: Baseline to 6 months
Change in Body Weight (kg)
Absolute change in body weight measured in kilograms (kg). Reported as mean change from baseline.
Time frame: Baseline to 6 and to 12 months
Change in Total Body Fat Mass (kg)
Change in total body fat mass measured by body impedance analysis (BIA). Reported as mean change from baseline (kg).
Time frame: Baseline to 6 months and to 12 months
Change in Body Fat percentage (%)
Change in fat percentage measured by body impedance analysis (BIA). Reported as mean change from baseline (%).
Time frame: Baseline to 6 and to 12 months
Change in Plasma Glycated Hemoglobin (HbA1c)
HbA1c plasma glycated hemoglogin measured in SI units mmol/mol, Reported as mean change from baseline.
Time frame: Baseline to 6 months and to 12 months
Change in HOMA-IR (Homeostatic Model Assessment of Insulin Resistance)
HOMA-IR calculated as fasting glucose (mmol/L) × fasting insulin (mU/L) / 22.5. Reported as mean change from baseline.
Time frame: Baseline to 6 and to 12 months
Change in Plasma Total Cholesterol (mmol/L)
Change in Plasma Total Cholesterol (mmol/L), Reported as mean change from baseline.
Time frame: Baseline to 6 months and to 12 months
Change in Plasma LDL Cholesterol (mmol/L)
Change in Plasma LDL Cholesterol (mmol/L). Reported as mean change from baseline.
Time frame: Baseline to 6 months and to 12 months
Change in Plasma HDL Cholesterol (mmol/L)
Change in HDL Cholesterol (mmol/L). Reported as mean change from baseline.
Time frame: Baseline to 6 months and to 12 months
Change in Plasma Triglycerides (mmol/L)
Change in Plasma Triglycerides (mmol/L). Reported as mean change from baseline.
Time frame: Baseline to 6 months and to 12 months
Change in Plasma C-Reactive Protein Concentration (mg/L)
Change in Plasma high-sensitivity C-Reactive Protein Concentration (hs-CRP, mg/L). Reported as mean change from baseline.
Time frame: Baseline, to 6 months and to 12 months
Change in Mitochondrial DNA amount in Subcutaneous Abdominal Adipose Tissue
Change in Mitochondrial DNA Amount in Subcutaneous Abdominal Adipose Tissue, measured by qPCR as the ratio of mitochondrial to nuclear genes. Reported as a mean change from baseline.
Time frame: Baseline to 6 months and to 12 months
Change in Mitochondrial DNA amount in Subcutaneous Breast Adipose Tissue
Change in Mitochondrial DNA Amount in Subcutaneous Breast Adipose Tissue, measured by qPCR as the ratio of mitochondrial to nuclear genes. Reported as a mean change from baseline.
Time frame: Baseline to 6 months and to 12 months
Change in Mitochondrial DNA amount in Subcutaneous Upper Arm Adipose Tissue
Change in Mitochondrial DNA Amount in Subcutaneous Upper Arm Adipose Tissue, measured by qPCR as the ratio of mitochondrial to nuclear genes. Reported as a mean change from baseline.
Time frame: Baseline to 6 months and to 12 months
Change in Mitochondrial DNA amount in Subcutaneous Lateral Upper Thigh Adipose Tissue
Change in Mitochondrial DNA Amount in Subcutaneous Lateral Upper Thigh Adipose Tissue, measured by qPCR as the ratio of mitochondrial to nuclear genes. Reported as a mean change from baseline.
Time frame: Baseline to 6 months and to 12 months
No study locations are listed for this record.
Plan to share: No — Individual participant data are not publicly shared due to data protection regulations; anonymized data may be available upon reasonable request after study completion.
No publications or documents are linked to this record.
This study is completed, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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University of Helsinki