Some claim that drinking beverages with meals is bad for your digestion.
Others say it can cause toxins to accumulate, leading to a variety of health issues.
Naturally, you may wonder if a simple glass of water with your meal could have negative effects — or if that’s just another myth.
This article provides an evidence-based review of how liquids with meals affect your digestion and health.
The basics of healthy digestion
To understand why water is thought to disturb digestion, it’s useful to first understand the normal digestive process.
Digestion starts in your mouth as soon as you start to chew your food. Chewing signals your salivary glands to start producing saliva, which contains enzymes that help you break down food.
Once in your stomach, food gets mixed with acidic gastric juice, which further breaks it down and produces a thick liquid known as chyme.
In your small intestine, chyme gets mixed with digestive enzymes from your pancreas and bile acid from your liver. These further break down the chyme, preparing each nutrient for absorption into your bloodstream.
Most nutrients are absorbed as the chyme travels through your small intestine. Only a small portion remains to be absorbed once it reaches your colon.
Once in your bloodstream, nutrients travel to different areas of your body. Digestion ends when the leftover materials are excreted.
Depending on what you eat, this whole digestive process can take anywhere from 24 to 72 hours.
Do liquids cause digestive problems?
Drinking enough fluids daily offers many benefits.
However, some people claim that drinking beverages with meals is a bad idea.
Below are the three most common arguments used to claim that liquids with meals harm your digestion.
Claim 1: Alcohol and acidic drinks negatively affect saliva
Some people argue that drinking acidic or alcoholic drinks with meals dries up saliva, making it more difficult for your body to digest food.
Alcohol does decrease saliva flow by 10–15% per unit of alcohol. Yet, this mainly refers to hard liquor — not the low alcohol concentrations in beer and wine (2Trusted Source, 3Trusted Source, 4Trusted Source).
On the other hand, acidic drinks seem to increase saliva secretion (5Trusted Source).
Finally, there’s no scientific evidence that either alcohol or acidic drinks, when consumed in moderation, negatively affect the digestion or absorption of nutrients.
Claim 2: Water, stomach acid, and digestive enzymes
Many claim that drinking water with meals dilutes stomach acid and digestive enzymes, making it more difficult for your body to digest food.
However, this claim implies that your digestive system is unable to adapt its secretions to the consistency of a meal, which is false (6Trusted Source).
Claim 3: Liquids and speed of digestion
A third popular argument against drinking liquids with meals states that fluids increase the speed at which solid foods exit your stomach.
This is thought to reduce the meal’s contact time with stomach acid and digestive enzymes, resulting in poorer digestion.
Yet, no scientific research supports this claim.
A study that analyzed stomach emptying observed that, although liquids do pass through your digestive system more quickly than solids, they have no effect on the digestion speed of solid food (7Trusted Source).
Liquids may improve digestion
Liquids help break down large chunks of food, making it easier for them to slide down your esophagus and into your stomach.
They also help move food matter along smoothly, preventing bloating and constipation.
Furthermore, your stomach secretes water, along with gastric acid and digestive enzymes, during digestion.
In fact, this water is needed to promote the proper function of these enzymes.
Water may reduce appetite and calorie intake
Drinking water with meals can also help you pause between bites, giving you a moment to check in with your hunger and fullness signals. This can prevent overeating and may even help you lose weight.
Additionally, one 12-week study showed that participants who drank 17 ounces (500 ml) of water before each meal lost 4.4 pounds (2 kg) more than those who did not (8Trusted Source).
Research also indicates that drinking water may speed up your metabolism by about 24 calories for every 17 ounces (500 ml) you consume (9Trusted Source, 10Trusted Source).
Interestingly, the number of calories burned decreased when the water was warmed to body temperature. This might be due to the fact that your body uses more energy to heat the cold water up to body temperature (9Trusted Source).
Still, the effects of water on metabolism are minor at best and not applicable to everyone (11Trusted Source, 12Trusted Source).
Keep in mind that this mostly applies to water, not drinks with calories. In one review, total calorie intake was 8–15% higher when people drank sugary drinks, milk, or juice with meals (13Trusted Source).
For most people, drinking liquids with meals is unlikely to negatively affect digestion.
That said, if you have gastroesophageal reflux disease (GERD), liquids with meals may negatively affect you.
That’s because liquids add volume to your stomach, which can increase stomach pressure like a large meal would. This can lead to acid reflux for people with GERD (14Trusted Source).
The bottom line
When it comes to drinking liquids with meals, base your decision on what feels best.
If consuming liquids with your food is painful, leaves you feeling bloated, or worsens your gastric reflux, stick to drinking liquids before or between meals.
Otherwise, there’s no evidence that you should avoid drinking with meals.
On the contrary, beverages consumed right before or during meals can promote smooth digestion, lead to optimal hydration, and leave you feeling full.
Just remember that water is the healthiest choice.