An interventional study of Ketogenic diet and Mediterranean diet in Acromegaly, sponsored by University of Palermo. Completed at 1 site in Italy. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-09-05.
Sponsored by University of Palermo · Not applicable, Interventional, and Treatment
This prospective, single-center, crossover study aims to evaluate the metabolic and hormonal effects of a ketogenic diet compared to a Mediterranean diet in patients with active acromegaly. Twenty-six adult patients with biochemically confirmed active acromegaly will undergo a three-week ketogenic diet followed by a three-week Mediterranean diet, with a two-week transitional phase. The primary outcome is the change in serum IGF-1 levels. Secondary outcomes include changes in anthropometric, biochemical, and inflammatory parameters. The study also explores the feasibility and safety of a structured ketogenic dietary intervention in this population.
Acromegaly is a rare endocrine disorder characterized by excessive secretion of growth hormone (GH) and insulin-like growth factor 1 (IGF-1), often leading to metabolic complications including insulin resistance, diabetes mellitus, and hepatic steatosis. Nutritional status is a key regulator of the somatotropic axis, and recent evidence suggests that specific dietary patterns can modulate GH and IGF-1 secretion. The ketogenic diet (KD), characterized by high fat, moderate protein, and very low carbohydrate intake, induces nutritional ketosis, improves insulin sensitivity, and reduces circulating insulin levels. These effects may influence the hepatic expression of GH receptors and IGF-1 production. Preliminary data suggest that KD may reduce IGF-1 levels in patients with acromegaly.
This study is designed as a single-arm crossover trial involving 26 patients with active acromegaly. All participants will follow a structured ketogenic diet for three weeks (\~1200 kcal/day, carbohydrates \<30 g/day), followed by a two-week transition phase, and then a Mediterranean diet for three weeks (\~1200 kcal/day, plant-based, rich in olive oil and fish). Baseline, post-KD, and post-Mediterranean assessments will include serum IGF-1 and GH levels, anthropometric measurements, body composition (via bioelectrical impedance analysis), liver enzymes, lipid profile, insulin resistance indices (HOMA-IR), and inflammatory markers (c-reactive protein, neutrophil to lymphocyte ratio, platelet to lymphocyte ratio).
The primary endpoint is the within-subject change in serum IGF-1 concentration. Secondary endpoints include changes in metabolic and inflammatory markers. Antidiabetic medications will be temporarily discontinued during the ketogenic phase under clinical supervision in patients not requiring insulin. The study is expected to provide novel insights into the impact of dietary modulation on the somatotropic axis in acromegaly and may inform future integrative therapeutic strategies.
Exclusion Criteria:
Participants will follow a structured ketogenic diet for 3 weeks (\~1200 kcal/day, \<30 g/day carbohydrates) to induce nutritional ketosis.
Behavioral: Ketogenic diet
Following a 2-week transition phase, participants will switch to a Mediterranean diet for 3 weeks (\~1200 kcal/day), rich in olive oil, vegetables, whole grains, and moderate protein intake.
Behavioral: Mediterranean diet
A structured, equicaloric ketogenic diet providing approximately 1200 kcal/day, consisting of high fat (70-80 g/day), moderate protein (80-90 g/day), and very low carbohydrate intake (20-30 g/day), primarily from non-starchy vegetables. The diet is administered for 3 consecutive weeks to induce nutritional ketosis. A sugar-free multivitamin supplement is provided throughout the intervention.
A structured Mediterranean diet administered for 3 weeks following a 2-week transition phase. The diet provides approximately 1200 kcal/day and emphasizes plant-based foods, extra virgin olive oil as the main fat source, moderate consumption of fish, dairy products, and whole grains, with limited red meat and processed foods.
Disease control
Change in serum IGF-1 levels after ketogenic and Mediterranean diets (paired comparison)
Time frame: 3 weeks
Metabolic outcomes
Change in fasting glucose (mg/dL)
Time frame: 3 weeks
Metabolic outcomes
Change in fasting insulin (µU/mL)
Time frame: 3 weeks
Metabolic outcomes
Change in HOMA-IR (unitless)
Time frame: 3 weeks
Anthropometric outcomes
Change in body weight (kg)
Time frame: 3 weeks
Anthropometric outcomes
Change in Body Mass Index (BMI) (kg/m²)
Time frame: 3 weeks
Anthropometric outcomes
Change in waist circumference (cm)
Time frame: 3 weeks
Liver outcomes
Change in transaminases (U/L)
Time frame: 3 weeks
Lean and fat masses
Change in lean and fat mass (only after ketogenic diet)
Time frame: 3 weeks
Plan to share: No — Individual participant data (IPD) will not be shared. This decision is based on institutional policy and ethical considerations, as the study involves a relatively small and identifiable patient population with a rare endocrine disorder. Data sharing may compromise patient confidentiality despite de-identification procedures.
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This study is completed, as verified in Aug 2025. You cannot join it, but the record below documents what was studied.
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University of Palermo