The Connection Between GERD, Melatonin, and Your Circadian Rhythm

Did you know that there is a connection between GERD/acid reflux, melatonin, and meal timing? If you experience GERD, acid reflux, or heartburn it may be due to a dysregulated circadian rhythm.

GERD and Circadian Rhythm

We have a master clock or central circadian clock located in the suprachiasmatic nucleus (SCN) in the brain which uses light as information to be in sync. However, every cell in your body also has a peripheral circadian clock which has its own circadian rhythm that is influenced by timing of food consumption. This means that eating late at night or eating at irregular times each day can disrupt central and/or peripheral circadian rhythms. When your external (central clock) and your internal (peripheral clocks) are not in sync this is called circadian misalignment.

The circadian rhythm in your GI tract is especially sensitive to changes in sleep and meal timing. It likes consistency and predictability. The GI tract has diurnal (daytime) fluctuations in gastric acid production and gastric pH is actually the lowest during evening/early morning. Studies have shown that night shift work is associated with a greater risk of developing GERD (aka acid reflux) compared to day shift workers which make sense if you consider their meal timing and dysregulated circadian rhythm.

Eating late at night or trying to eat your largest meal of the day, especially something that is harder to digest like a steak, later in the evening after dark is going to be very difficult to digest before bed. You need hydrochloric acid (HCl) to break down protein, so if your food doesn't get properly digested then this can cause GERD or acid reflux at bedtime.

GERD and Low Melatonin

The central clock (SCN) also regulates melatonin production and sleep. Disruptions in circadian rhythm also suppresses melatonin production. This is important because of the role that melatonin plays in increasing the lower esophageal sphincter (LES) pressure which separates the esophagus from the stomach and keeps gastric acid and food in the stomach. People with GERD often have lower melatonin levels, which likely contributes to the issue.

We actually make melatonin all day long, not just in the evening at bedtime. The signaling for this comes from our daytime exposure to the sunlight, as well as our light environment in the evening. So, get outside with naked eyes first thing in the morning, eat your last meal (no snacking!) at least 3-4 hours before bed, and avoid artificial and blue lights after dark. I highly recommend using red or amber blue light blockers after sunset. My favorite brand and the one's that I use are from Bon Charge. Use code NOURISH15 for 15% off.