- Researchers say intermittent fasting can reduce inflammation in the body.
- Inflammation is one way the body fights infection, but if there is too much inflammation that can lead to various diseases.
- Experts say many people have an excess of inflammation because they eat too much and eat too often.
Intermittent fasting and related diets are having a moment. And there might be some good reasons to extend their 15 minutes of fame.
A new study has concluded that intermittent fasting reduces inflammation, a condition that can lead to various diseases such as diabetes, multiple sclerosis, and inflammatory bowel syndrome.
That reduction, the study found, was due to a reduction in cells that cause inflammation — called “monocytes” — in the blood.
Researchers also said the monocytes that were in the blood were less inflammatory than they were in people and mice not on an intermittent fasting diet.
The reason for the difference may be not so much that it’s good to starve yourself as that everyone else is eating too much.
“Especially in the Western world, people eat all the time and that’s a fairly recent habit in human evolution,” Dr. Miriam Merad, an author of the new study and director of the Precision Immunology Institute at the Icahn School of Medicine at Mount Sinai in New York, told Healthline.
Inflammation is a useful tool our bodies use to fight infections.
But, Merad suggested, the quantity of inflammation-causing cells we typically have today may be more a product of this overeating than necessity.
“We wondered whether the number of monocytes we call normal is, in fact, not normal — in fact puts us at risk… and may be unnecessary, may reflect our recent dietary habits,” Merad said. “Somehow we have acquired dietary habits that are putting us at risk for inflammation.”
The study findings answer how that connection between diet and inflammation works.
But the lessons that eating less can reduce inflammation and problems associated with it aren’t new.
“We’re consistently over-fueling, and that then leads to what I would call inflammatory pathways,” Kristin Kirkpatrick, MS, RDN, who manages wellness nutrition services at the Cleveland Clinic Wellness Institute, told Healthline. “So time-restricted eating limits that.”
“That’s not to say that food isn’t important,” she added.
It’s just about moderation.
One thing Kirkpatrick has recommended to some of her clients is to only eat between certain hours of the day as well as avoiding sugars.
She suggested only eating between 11 a.m. and 7 p.m. as an example, which somewhat mimics circadian rhythms.
This time-restricted eating has “been shown to improve overall gut health and microbiota, which has been shown to have big impact on health,” she said.
In the new study, the human participants did something a bit different.
They weren’t allowed to eat between noon and 3 p.m. on the first day, and then not between 8 p.m. that same day until 3 p.m. of the following day. They were allowed to drink water.
At 3 p.m. on both days, blood was drawn to test white blood cell levels. White blood cells, of which monocytes are one type, are the body’s protection against infection and typically indicate inflammation.
“We use them to learn whether someone is sick and there are numbers that are considered normal,” Merad said. “People with an infection have big numbers. What we saw here is a very strong drop in monocytes.”
Other studies have found somewhat similar things.
A 2013 study concluded that fasting for more than 24 hours may lower inflammation by reducing oxidative stress in cells.
A 2014 study found that both intermittent fasting and alternate-day fasting were as effective as limiting calorie intake at reducing insulin resistance.
But Merad hopes to look further into different diets — including into any potential negative impacts they may have.
“And then we will really start to understand whether we can make strong recommendations to the public,” she said.
Unlike diets that cut out or down on certain foods, intermittent fasting typically involves just not eating at certain times.
Typically, that means refraining for 16 to 24 hours, usually twice a week. At its most extreme, people will refrain from food for 48 hours.
“Intermittent fasting is becoming very fashionable, but some people are doing crazy things like not eating for days,” Merad noted.
But the point isn’t to stop eating.
“What I’m saying is we probably eat too much and too often — definitely we eat too often,” she said.