People with Crohn's disease often ask, “What should I eat?” Doctors find this question hard to answer because diet research is limited.
Now a team from Stanford Medicine and other centers ran a national trial. They discovered that a short‑term, low‑calorie plan improved symptoms and lowered inflammation in patients with mild‑to‑moderate Crohn's disease.
Crohn's Disease and Current Treatments
About one million Americans have Crohn's disease. It causes belly pain, diarrhea, cramps, and weight loss. For mild cases, steroids are the only approved medicine, but they can cause serious side effects when used for a long time.
How the Fasting‑Mimicking Diet Was Tested
The study enrolled 97 adults across the United States. Sixty‑five people followed a fasting‑mimicking diet (FMD) and 32 kept eating as usual. The trial lasted three months.
During the FMD, participants ate about 700‑1,100 calories each day for five straight days each month. They received plant‑based meals for those days and ate normally the rest of the month.
Symptom Improvements
At the end of the study, roughly two‑thirds of the FMD group said their symptoms got better. In the control group, fewer than half reported any improvement.
Some participants felt tired or got headaches, but no serious side effects were seen.
Reductions in Inflammation
Researchers also measured inflammation inside the body. They found that the FMD group had lower levels of fecal calprotectin, a protein that signals gut inflammation.
Other inflammation‑related molecules, such as certain fatty‑acid‑derived lipids, also dropped. Immune cells from these participants released fewer inflammatory signals.
The team is now checking whether changes in gut bacteria might explain the benefits.
What’s Next?
Scientists say more work is needed to fully understand how this diet helps people with Crohn's disease and to discover which patients will respond best.
The study was funded by several health foundations and government grants.