Dietary Interventions and Vitamin D3 Replacement in Pituitary Tumors: a Systematic Review
In brief
Low-carb ketogenic diet lowers IGF-I levels in acromegaly patients
A systematic review of eight studies (355 patients) found that an isocaloric very low-carbohydrate ketogenic diet reduced IGF-I concentrations in people with acromegaly, while similar low-carb or calorie-restricted diets improved weight and metabolic markers in Cushing's disease, prolactinomas, and hypopituitarism. Vitamin D3 supplementation also cut vertebral fracture risk in acromegaly, but overall evidence remains limited and larger trials are needed.
- Journal
- European journal of endocrinology (Q1)
- Published
- 20 September 2026
- Study design
- Systematic review / meta-analysis of RCTs
- Evidence level
- Level 1, High (CEBM 1a)
- Authors
- L C Te Nijenhuis-Noort, R van de Groef, J Refardt, I C M Pelsma, N R Biermasz, K A Berk, et al.
- PMID
- 42764013
- DOI
- 10.1093/ejendo/lvag182
Why clinicians should know about it
- Picked for Biochemistry (medical) (paper of the day, 21 September 2026): Dietary interventions improve metabolic outcomes
Abstract
OBJECTIVE: Pituitary neuroendocrine tumors (PitNETs) cause hormonal imbalances that impair metabolic health and quality of life (QoL). Dietary interventions may mitigate these comorbidities. This review evaluated the effectiveness of dietary strategies in improving disease-related metabolic, and bone outcomes in patients with PitNETs. DESIGN: Systematic review of interventional and observational studies on dietary interventions in acromegaly, Cushing's disease, prolactinomas, and hypopituitarism. METHODS: A systematic search was performed on January 20th, 2026. Eligible studies assessed dietary interventions targeting metabolic or bone-related outcomes. Risk of bias was evaluated using ROBINS-I and the Newcastle-Ottawa Scale. Extracted outcomes included dietary intake, body composition, metabolic parameters, biochemical control, and bone health. RESULTS: Of 2,256 screened records, eight studies (355 participants) met the inclusion criteria, including five interventional and three observational studies. In acromegaly, an isocaloric very low-carbohydrate ketogenic diet (VLCKD) reduced IGF-I levels. In Cushing's disease, VLCKD and energy-restricted diets (ERD) improved BMI and metabolic parameters. In prolactinoma, ERD combined with increased physical activity improved weight and biochemical control. In hypopituitarism, ERD with increased physical activity and sibutramine improved body composition and metabolic outcomes. Vitamin D replacement reduced vertebral fracture risk in acromegaly and improved insulin sensitivity and lipid levels in Cushing's disease. CONCLUSIONS: Evidence on dietary strategies for PitNET management is limited. Low-carbohydrate and energy-restricted diets may improve adverse metabolic comorbidities, while vitamin D3 replacement shows potential benefits for insulin sensitivity in Cushing's disease and fracture risk in acromegaly. Larger randomized trials are needed to confirm effects on disease control, comorbidities, and QoL.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.