And by bowels, we really mean the important role that water plays in having healthy bowel movements. This is a serious yet often overlooked health issue for many Americans, supported by a swath of studies on the prevalence of chronic constipation in North America. Some research indicates up to 58% of people may suffer from chronic constipation (1). Another interesting fact? Americans spent over $875 million on laxatives in 2011 alone (2). Think about it—a nearly one-billion dollar constipation price tag?!
So, what’s water got to do with it?
If you’ve ever tried to lose weight, you’ve likely been told to drink a glass of water before every meal. It’s a pretty common suggestion and, when used appropriately, it can certainly help reduce the amount of food you eat. From a digestive standpoint, having water in your belly before consuming a meal also stretches your stomach and starts triggering the neural pathways to your brain that indicate fullness.
Of course, water alone will not satiate you. The brain knows the difference between water and nutrients. But if overeating is a common habit, then drinking water before a meal will help.
Consuming water with your food is also a helpful practice for healthy digestion. The process begins in the mouth, continues down the esophagus and into the stomach. The act of swallowing is much easier (and more pleasant!) when our food is moist—hence the benefit of sipping on water with your meal.
After your food travels down your esophagus and into your stomach, it gets churned and liquefied. Digestive enzymes in the stomach help break down protein and continue breaking down carbohydrates. But the main job of the stomach is to liquefy your food. Your stomach has three muscle layers: the longitudinal layer, the circular layer and, the oh-so-important oblique layer (a.k.a. the muscularis externa.) These three layers, especially the oblique layer, allow the stomach to churn, mix and pummel food into liquefied matter called chyme (3).
Liquefying your food is an essential step in digestion. The more broken down your food is, the more likely you’ll absorb all of the nutrients from it. But have you ever thrown a bunch of fruits and vegetables, without water or ice, into a blender to make a smoothie? You’ll notice that without liquid it turns into a chunky gazpacho-like texture. But add some water, cucumber water or almond milk, and you’ll get a smooth liquid that can easily pass through a straw. Physiologically speaking, being hydrated will ensure you have water in your stomach to aid in the liquefaction process resulting in chyme that is smoother and easier to pass to the duodenum (i.e. the first part of the small intestine).
After chyme leaves your stomach, it moves to the small intestine where more digestive juices are released from the gallbladder and the pancreas. These digestive juices break down your food into smaller and smaller units, until finally the macronutrients (e.g. amino acids, monosaccharides, fatty acids) and micronutrients (e.g. vitamins, minerals, phytonutrients) can be absorbed.
Finally, proper hydration is key to normal bowel movements or “healthy elimination.” Healthy elimination translates to 1-3 daily, easily passed bowel movements. Without proper hydration, your stool becomes hard to pass, causing pain and constipation.
Why does water matter in elimination?
The remaining indigestible food residue moves from your small intestine to your large intestine (i.e. the colon). The colon is where you reabsorb water from the food residue depending on how much is needed in other parts of the body. Now, this part is critical to understand. If you are not properly hydrated, more water will be absorbed from undigested food particles leaving your bowel movement firm, hard to pass and painful.
When you take laxatives or consume foods/drinks that have a natural laxative effect (think coffee), you’ll likely have a smooth, easy to pass bowel movement. But laxatives mask your body’s functional ability, and you can’t determine your hydration status by the state of your bowel movements. As long as you aren’t consuming medicines that cause digestive disturbances, constipation is the body’s natural way of informing you that perhaps your water intake is low. Being properly hydrated, barring any gut dysfunction, should produce easy to pass, large stools.
In short, hydration matters for healthy digestion and elimination—two key functions to optimal health. What can you do to improve your hydration status for better digestion?
Assess your poop, with and without the aid of laxatives or coffee. Do you have hard or easy to pass bowel movements? Try upping your water intake and assess the results.
Drink a glass of water before each meal to help your stomach do its job. (Please note: this approach will not benefit those who’ve had gastric bypass surgery.)
Sip water throughout your meal. It will help food move easily through your digestive canal.
Start your morning with two large glasses of water before you consume food. You’ve been without water the entire night, and hydrating first thing in the morning will promote a healthy bowel movement earlier in the day.
Pay attention to hunger cues. Many of us get hunger and thirst cues confused. If you’re hungry but just ate, try drinking water to hydrate your system before making the decision to eat again.
Pinto Sanchez, M. I., & Bercik, P. (2011). Epidemiology and burden of chronic constipation. Canadian Journal of Gastroenterology, 25(Suppl B), 11B–15B.
What You Need to Know About the Over-The-Counter Drug Industry. (2014 6–11). Retrieved July 27, 2015, from http://pharma.about.com/od/Over-the-Counter-Medicine/a/The-Over-the-counter-Drug-Industry.htm
Marieb, E. N. (2011). Essentials of Human Anatomy & Physiology (10 edition). San Francisco, CA: Pearson.
Humphries, C. (2010, October 18). Does drinking water with meals help with digestion? Boston Globe Q. I’ve always been told that drinking water with meals helps with digestion, is this true? Courtney Humphries October 18, 2010. Boston.com. Retrieved from http://www.boston.com/news/health/articles/2010/10/18/doesdrinkingwaterwithmealshelpwith_digestion/
Arnaud, M. J. (2003). Mild dehydration: a risk factor of constipation? European Journal of Clinical Nutrition,57 Suppl 2, S88–95. http://doi.org/10.1038/sj.ejcn.1601907
National Institute of Diabetes and Digestive and Kidney Diseases. (2013, September 18). Your Digestive System and How It Works. Retrieved July 27, 2015, from http://www.niddk.nih.gov/health-information/health-topics/Anatomy/your-digestive-system/Pages/anatomy.asp