One Week of Fasting Eased Rheumatoid Arthritis Symptoms Faster Than Diet Alone: What the Research Shows

One Week of Fasting Eased Rheumatoid Arthritis Symptoms Faster Than Diet Alone: What the Research Shows

Medical disclaimer: This article summarises published research for informational purposes only. It is not medical advice and is not a substitute for guidance from a qualified health professional. Always consult your doctor before starting any fasting protocol, especially if you have an existing health condition or take medication.

Study at a Glance

What This Study Looked At

Researchers at Charité – Universitätsmedizin Berlin wanted to know whether a short supervised fast, followed by a plant-based diet, could outperform a standard guideline-based anti-inflammatory diet in people with active rheumatoid arthritis (RA). RA is an autoimmune condition where the immune system attacks joint tissue, and earlier fasting research — including a well-known 1991 Lancet study — had suggested fasting could calm disease activity in the short term. This trial, known as NutriFast, set out to test that idea in a modern, randomized design. For background on the gut-related mechanisms researchers think may be involved, see how fasting addresses the three root causes of autoimmune disease.

Who Was Studied

Participant profile: Mean age 51.98 ± 9.4 years; 92% female; average RA symptom duration of 6.8 ± 8.1 years; average BMI 25.0 ± 3.7 kg/m²; 78% of participants were rheumatoid factor and/or anti-CCP antibody positive at baseline. Baseline disease activity (DAS28-CRP) averaged 4.0 ± 1.3, indicating moderate disease activity.

How the fasting protocol worked in this study: The fasting group followed a modified fast of roughly 7 to 10 days with a very low daily calorie intake (around 500 kcal or less), medically supervised as is standard for therapeutic fasting programs in Germany. This was followed immediately by 11 weeks of a whole-food, plant-based diet, for a combined 12-week intervention period matching the comparison group's duration.

What the Researchers Found

Disease activity (DAS28)

• Both groups improved significantly on the primary composite disease activity score, with no statistically significant difference between them by week 12 — the trial's primary endpoint was not met.
• The fasting group's functional disability score (HAQ-DI) improved rapidly, within the first 7 days of fasting, and stayed stable for the rest of the 12 weeks — while the standard-diet group didn't show comparable improvement until weeks 6 and 12.
• 9 of 25 patients in the fasting group achieved an ACR50 response (a 50%+ improvement in core RA symptoms) or better, compared with 3 of 25 in the standard-diet group.

Weight and cardiovascular risk markers

• Fasting group: average weight loss of 3.9 kg (p<0.001)
• Standard-diet group: average weight loss of 0.7 kg (not statistically significant, p=0.146)
• Weight and related cardiovascular risk factors improved more strongly in the fasting group than the standard-diet group over the 12 weeks.

What Did Not Change

• The trial's pre-specified primary endpoint — functional disability at 12 weeks — showed no statistically significant difference between the two diet strategies.
• Neither group's report highlighted significant changes in lean/muscle mass as an outcome; body composition beyond weight was not a primary focus of this trial.

What the Researchers Concluded

The authors concluded that a short fast followed by a plant-based diet was not superior to a standard guideline-based anti-inflammatory diet on the primary functional disability outcome at 12 weeks, but that fasting produced faster early symptom relief and greater short-term improvements in weight and cardiovascular risk factors — suggesting fasting may offer a useful, faster-acting complement to dietary changes in RA management.

What This Means If You Fast

• Fasting may bring faster relief, not necessarily better long-term outcomes. The fasting group felt functional improvement within a week, but by 12 weeks, a well-designed standard anti-inflammatory diet closed the gap.
• This was a supervised, low-calorie modified fast — not a casual DIY protocol. A 7-to-10-day fast at very low calories in people with an active autoimmune condition should only be attempted with medical oversight, not improvised.
• Weight loss and cardiovascular markers moved more in the fasting group, which may matter for RA patients, since cardiovascular disease risk is elevated in rheumatoid arthritis.
• This adds to — but doesn't replace — the broader autoimmune fasting literature. For related historical and mechanistic context, see fasting and rheumatism: what 277 historical cases showed and does intermittent fasting reduce inflammation.
• Diet quality after a fast still matters. Both groups in this trial followed structured, guided diets afterward — the takeaway isn't "fast then eat anything," it's that what follows the fast shapes the outcome.
• If you have RA or another autoimmune condition, talk to your rheumatologist before fasting, especially around medication timing and disease activity monitoring.

Study Limitations

• Small sample size (50 completers) limits statistical power, and the trial itself was labeled exploratory.
• Open-label design — participants and researchers knew which group they were in, which can influence self-reported outcomes like pain and disability scores.
• 92% of participants were women, so findings may not generalize evenly to men with RA.
• Single-center study conducted at one hospital in Germany, which may limit generalizability to other populations and healthcare settings.
• The primary endpoint was not statistically significant between groups, meaning the faster symptom relief in the fasting group should be interpreted as a secondary, exploratory finding rather than a confirmed treatment effect.
• Autoantibody titers (RF, anti-CCP) were reported at baseline but were not the primary tracked outcome across the 12-week intervention in available summaries.

Source

Hartmann AM, Dell'Oro M, Spoo M, Fischer JM, Steckhan N, Jeitler M, Häupl T, Kandil FI, Michalsen A, Koppold-Liebscher DA, Kessler CS. (2022). To eat or not to eat—an exploratory randomized controlled trial on fasting and plant-based diet in rheumatoid arthritis (NutriFast-Study). Frontiers in Nutrition, 9:1030380. PMID: 36386907

Frequently Asked Questions

Can fasting help rheumatoid arthritis symptoms?

This 2022 randomized trial found that a 7-day supervised fast led to faster improvement in functional disability scores compared to a standard anti-inflammatory diet, though by 12 weeks both approaches produced similar overall disease activity improvement.

How long was the fast in this rheumatoid arthritis study?

Participants fasted for approximately 7 to 10 days on a modified, medically supervised protocol with very low calorie intake (around 500 kcal or less per day), followed by 11 weeks on a plant-based diet.

Did fasting cure rheumatoid arthritis in this study?

No. Fasting did not cure RA or outperform the standard diet on the trial's primary outcome. It showed faster early symptom relief and greater short-term weight loss, but the disease activity improvements were statistically similar between groups by week 12.

Is it safe to fast with an autoimmune condition like RA?

This trial's fasting protocol was medically supervised, which the researchers emphasize as important — a low-calorie extended fast in someone with an active autoimmune condition and possibly on medication should not be attempted without a doctor's guidance.

What diet followed the fast in this study?

The fasting group transitioned into 11 weeks of a whole-food, plant-based diet, while the comparison group followed a standard guideline-based anti-inflammatory diet for the full 12 weeks.

Related Research and Articles

• Fasting and Rheumatism: What 277 Historical Cases Showed
• Fasting and Rheumatoid Arthritis: 1991 Lancet Study Findings
• How Fasting Addresses the Three Root Causes of Autoimmune Disease in Women
• Does Intermittent Fasting Reduce Inflammation?
• Intermittent Fasting and Autoimmune Conditions in Women
• How Fasting Heals the Gut: Rest, Repair, and Renewal

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