Don’t we all want a gut that runs as smoothly and predictably as a railroad train? Although there isn’t much scientific research on when to eat for optimal digestion, expert advice has long ranged from three to five hours.

“For the average person, this distribution of meals is probably the best. This will better allow your gut to “clean itself up,” says nutritionist Amanda Sauceda, M.D., a nutritionist. Between meals, the gut acts as a “migratory motor complex,” according to Sauceda, contracting to push undigested food through the digestive system. “When you eat, the migrating motor complex is interrupted. You don’t want to eat all the time because the ‘cleanse’ will stop.”

On the other hand, if you suffer from indigestion, you may want to move your meals closer together. People who have trouble digesting fat or experience acid reflux after eating a large meal may feel better eating smaller portions throughout the day. Your doctor or dietitian can advise you on best practices for meal timing for conditions such as IBS, IBD, or GERD.

Fortunately, however, there’s no need to worry that meal spacing will affect how well you absorb nutrients in any way. “Your digestive system is extremely smart and adaptive, so when you eat, it supplies the right enzymes to help break down food for better absorption,” Sauceda says.