There are trillions of microorganisms living in your intestines, helping to break down your food and make nutrients, like B vitamins and vitamin K. 12 Fasting can be one of the many ways to improve overall gut health by helping these microorganisms thrive.
Initial evidence suggests that intermittent fasting may benefit your gut health, particularly by increasing the diversity of your gut microbiome and the “good” gut bugs that make their home there. Certain foods may improve your gut health while intermittent fasting, as well as help support you during fasting periods.
Fasting during prolonged periods gives the gut the time it needs to restore its integrity. This is especially important for those with “leaky gut”, also called intestinal permeability, where the gut lining is weakened thereby allowing toxins, partially digested foods and pathogens to enter the bloodstream.
Fasting alters the gut microbiome, impacting bacterial taxa and gene modules associated with short-chain fatty acid production.
Both the time restricted eating and modified fasting diets showed reduced inflammation in the gut and brain, improvements in the gut barrier, and an increase in anti-inflammatory related gut bacteria.
Anti-inflammatory drugs are often the first step in the treatment of ulcerative colitis, typically for mild to moderate disease. Anti-inflammatories include aminosalicylates, such as mesalamine (Delzicol, Rowasa, others), balsalazide (Colazal) and olsalazine (Dipentum).
Sears suggests 12 to 14 hours of fasting overnight, with your eating window ending between 5 and 8 p.m. Don't restrict your calorie intake during the eating periods. Most of your gut bugs need food to survive—not to mention you need food for energy and other functions—said Devkota.
The most immediate organ affected by a fast is the pancreas. During times of low plasma glucose, the pancreas will release more glucagon from the alpha cells found in the islets of Langerhans. Glucagon will mainly affect the liver as it stores most of the glycogen in the body.
Digestive issues
The reduction in food intake that comes along with some intermittent fasting regimens may negatively affect your digestion, causing constipation and other side effects. Plus, changes in diet associated with intermittent fasting programs may cause bloating and diarrhea ( 8 ).
Yep, in some cases intermittent fasting can totally throw your bowel movements out of whack. Constipation isn't the only possible side effect of intermittent fasting. Others have also claimed they've experienced the opposite issue, like diarrhea, in some cases.
Dr. Longo proposes that the human body evolved a natural self-repair mechanism that is switched on during fasting and allows for the repair of damaged cells and organs. In the modern-day with no imposed fasting, these cycles of renewal may remain dormant.
That's because the fasting pattern can help promote the movement of the motor complex, which can improve certain irritable bowel syndrome symptoms, especially when there is an overgrowth of sugar bacteria.
The researchers concluded that fasting therapy could be useful for treating moderate to severe patients with IBS. Unfortunately, patient allocation was neither blinded nor randomized; so, the comparison to the control group doesn't mean much.
The verdict: In most cases, fasting will help your body recover from bloating. Fasting, even if it's just for a few hours, could be just the ticket.
The best way to avoid these side effects is to stick to shorter fasting periods of up to 24 hours — especially when you're just starting out. If you want to increase your fasting period to more than 72 hours, you should seek medical supervision.
For some, fasting may cause problems. For example, studies have found that people who regularly fast more than 16 or 18 hours a day have a higher risk of gallstones. They're also more likely to need surgery to remove the gallbladder.
As such, fasting can increase stress levels and disrupt sleep. Dehydration, hunger or lack of sleep during a fasting period can also lead to headaches. Fasting can also cause heartburn; lack of food leads to a reduction in stomach acid, which digests food and destroys bacteria.
The biggest way to tell if your leaky gut is healing is when your energy and vitality have returned, you've regained mental clarity, your mood has improved, you've returned to your ideal weight, and you feel like your best self. It's important to remember that, as with most health concerns, gut health is on a spectrum.
The ability of intermittent fasting to lower inflammation has been proven (25). More recent research has shown that alternate-day fasting and time-restricted fasting methods appear to improve gut permeability. This means they make the gut less leaky.
Intermittent fasting: Intermittent fasting is a weight loss strategy that involves going through periods of eating and not eating. It may help reduce your levels of visceral fat.