Randomised controlled trialindependent cross-checkabstract checked★ key study I-FAST-107 in-depth review

Fasting then vegetarian diet in rheumatoid arthritis

Controlled trial of fasting and one-year vegetarian diet in rheumatoid arthritis.

Overview

Kjeldsen-Kragh J et al.. Lancet 1991 · PMID 1681264 · DOI 10.1016/0140-6736(91)91770-u

People with RA who fasted and then ate a vegetarian diet had fewer painful joints and lower inflammation over a year than controls.

Does the study support the specific claim? Partly · Methodological quality: moderate

Study explained simply

What did the researchers want to find out?: Test a fasting-plus-diet regimen in RA.
How was the study done?: 53 patients randomised; 1-year follow-up.
How many people, animals or samples were studied?: 53 Norwegian patients with RA.
What was actually found?: Improvement in joint counts, pain, stiffness, ESR and CRP in the diet group; persisted at 1 year.
How large was the observed effect?: Not given in abstract.
What do the results mean in everyday life?: A diet regimen may add benefit for some RA patients alongside their medicines.
What are the study's limitations?: Small, unblinded, confounded by setting.
What does it say about Elawady's specific claim?: Partly supports 'fasting treats joint pain'; does not support stopping medication.
Do the results apply to Germany and Europe?: Applies; same physiology.
What can explicitly not be concluded from this study?: Effect of fasting alone; effect in lupus or MS.

Authors: Kjeldsen-Kragh J et al.
Journal: Lancet
Year: 1991
Identifier: PMID 1681264 DOI 10.1016/0140-6736(91)91770-u
Verification: verified – PubMed efetch 2026-10-26; Crossref update-to/updated-by check
Retracted: no
Corrections: none
Extent checked: abstract only
Conflicts of interest and funding: not stated in abstract

Does a subtotal fast followed by a one-year vegetarian diet improve rheumatoid arthritis?

Study design: Randomised controlled trial – Randomised, single-blind controlled trial
Population: Patients with rheumatoid arthritis
Country: Norway
Period: not stated in abstract
Sample size: 53 (27 diet, 26 control)
Inclusion and exclusion criteria: not stated in abstract

Exposure / intervention: 7-10-day subtotal fast at a health farm, then gluten-free vegan diet for 3.5 months, then lactovegetarian diet
Comparator: 4 weeks at a convalescent home with ordinary diet
Endpoints: Tender and swollen joints, Ritchie index, pain, morning stiffness, grip strength, ESR, CRP, WBC, HAQ
Statistical methods: Between-group comparisons

Results: After 4 weeks the diet group improved significantly in tender joints, Ritchie index, swollen joints, pain score, morning stiffness, grip strength, ESR, CRP, white cell count and HAQ; the control group improved only in pain. Benefits persisted at one year with significant advantages in all measured indices.
Absolute risks: not reported
Authors' conclusion: This dietary regimen seems to be a useful supplement to conventional medical treatment of rheumatoid arthritis.

Orienting tool: RoB 2
Type of assessment: simplified assessment (abstract only)
Full formal assessment: no
Overall risk of bias: high
Rationale: Lack of blinding of participants, different care settings, small sample.

Direction consistent; effect sizes not in abstract. Benefit is attributed to the whole regimen, not to fasting alone.

Strongest classic supporting evidence for 'fasting helps joint pain' - as a supplement to medical treatment, followed by a long-term diet change.

Universal biology; applies in Europe and Egypt.

Supports a modest add-on effect in RA; authors explicitly frame it as supplement to conventional treatment.

Multidimensional assessment
Multidimensional assessment
Authenticity of the source	verified
Methodological quality	moderate
Risk of bias	high
Precision of results	low
Directness	indirect
Reproducibility	partly replicated
Consistency with the overall evidence	mixed
Regional transferability	moderate
Adequacy of the interpretation (by the archive)	not applicable