- A short-term calorie deficit may be beneficial for people with Crohn’s disease.
- Research suggests that a calorie deficit for five consecutive days out of every month for three consecutive months could improve symptoms and biological indicators of the disease.
- Experts say some people with Crohn’s disease would not benefit from such an approach due to risks like malnutrition, weight loss, and dehydration.
A short term, calorie-restricted diet may provide significant improvement to physical symptoms for people with Crohn’s disease.
Researchers from Stanford found that following a fasting-mimicking diet (FMD) also improved biological indicators of the disease. The results were published on January 13 in
“We were very pleasantly surprised that the majority of patients seemed to benefit from this diet,” Sidhartha R. Sinha, MD, an assistant professor of gastroenterology and hepatology at Stanford and the senior author on the paper, said in a news release.
“We noticed that even after just one FMD cycle, there were clinical benefits. We have been very limited in what kind of dietary information we can provide patients. This study will give physicians evidence to support recommendations in an area that patients are very curious about,” Sinha continued.
The study involved 97 people living with mild to moderate Crohn’s disease from across the United States and examined both symptoms and biological indicators of the condition.
The fasting mimicking group involved 65 study participants, while 32 were in a control group and followed their usual diet.
Those in the fasting-mimicking group ate a significant calorie deficit for five consecutive days out of the month for three consecutive months.
They consumed between 700 and 1,100 calories per day and were given plant-based meals. For the rest of the month, they continued to eat their usual diet.
The researchers found that, at the conclusion of the three months, two-thirds of those in the fasting-mimicking group experienced an improvement in their symptoms.
By comparison, at the end of the three months, less than half of those in the control group experienced an improvement in their symptoms.
The researchers concluded that any improvement in this group was likely due to natural fluctuations of Crohn’s disease and following their standard care regimen.
Among those who followed the fasting-mimicking diet, there were also significant changes in biological indicators of disease. These were determined by samples of both stool and blood.
“Our goal in collecting these and other biospecimens was to dig deeper into why there’s this differential response,” Sinha said. “Can we find mechanisms to explain the findings and signatures that might help predict patients who will respond to the diet?”
They found that those who followed the fasting-mimicking diet had less calprotectin protein in their stool, indicating less gut inflammation.
They also found that the immune cells of this group produced less of several different types of inflammatory molecules.
Emeran Mayer, MD, PhD, a gastroenterologist at UCLA, who wasn’t involved in the study, said the results are interesting.
“The study was done by a group of highly respected dietary experts and was well designed. Even though at first glance the results with the FMD seem surprising, there are multiple biological reasons to explain the benefit of the diet in this patient population,” he told Healthline.
“It is remarkable, but it is also important to remember that the majority of patients had mild disease and that such patients can show placebo responses of up to 40%. The control group, without any dietary intervention, showed a response rate of 40%. As the diet group was not blinded to the diet change, it is plausible that part of the surprising effectiveness could be related to a placebo effect.” Mayer continued.
The most common symptoms of Crohn’s disease include cramping, pain in the abdomen, diarrhea, and weight loss.
There were no serious adverse events reported among the participants of the calorie restriction study. However, some in the fasting mimicking group reported headaches and fatigue.
Experts say that while a calorie-restricted diet may be helpful for some living with Crohn’s disease, for others it would be inappropriate.
“That’s a very low calorie intake, even if brief,” Rudolph Bedford, MD, board certified gastroenterologist at Providence Saint John’s Health Center in Santa Monica, CA, told Healthline. Bedford wasn’t involved in the study.
“In selected well-nourished adults, it can be tolerable. But Crohn’s patients usually are a special population because of unintentional weight loss, nutrient deficiency, some of them are at risk of dehydration,” he said.
“Safety depends on who’s doing it and how it’s supervised. So people who are already underweight, malnourished, pregnant, frail… have various eating disorders… diabetics, or they have frequent flares, are not really good candidates for this type of treatment. So I certainly would not self-prescribe this. It should be co-managed with a GI team and a dietitian with hydration guidance,” Bedford continued.
Prior research has shown that a fasting-mimicking diet in individuals with Crohn’s disease can reduce levels of a marker of systemic inflammation, known as C-reactive protein.
“The effects seen on inflammatory markers made this an appealing diet to study in Crohn’s disease since many patients with this disease also have elevated inflammatory markers,” Sinha said.
“There have been studies and research showing that low calorie/fasting-mimicking days can decrease inflammation in the body, which is some of what they were looking at in this study too. So, if fasting mimicking/calorie reduction can aid in Crohn’s remission, it is definitely worth looking deeper into,” Dana Hunnes, PhD, senior dietitian at UCLA Health, told Healthline. Hunnes wasn’t involved in the study.
“Over the last few years, this is an area of research that is burgeoning, and I look forward to seeing how much more we learn.”
The researchers say they are now doing more work to determine whether changes to the gut microbiome may be part of the reason some people with Crohn’s disease see a benefit from a fasting mimicking diet.
“There’s still a lot more to be done to understand the biology behind how this and other diets work in patients with Crohn’s disease,” Sinha said.
