We have probably all heard by now that soda is bad for weight loss and for our health, but how about carbonated (or seltzer) water? Is that good or bad for weight loss, and what about our health?
Staying Hydrated is Good for Weight Loss
When we are told by physicians or professionals to lose weight, often they recommend increasing water intake.
Evidence shows staying hydrated is associated with weight loss, independent of changes in diet and activity (Stookey et. al, 2008). In addition, being chronically dehydrated (called ‘hypohydration’) is also associated with CV disease, obesity, cancer, and Alzheimer’s disease (for review see Thornton, 2016), and could be involved in the disruption of metabolic of the pathways in the same diseases (for review see Cavanaugh et. al, 2007). Therefore increasing water intake could be at least somewhat preventive for these diseases.
In contrast, drinking soda and sugary beverages is associated with weight gain. For example, one study showed a 0.47 pound increase in weight for women after increasing just by 1 soda per week. In addition, (Liebman et. al, 2003) found a doubling in the likelihood of obesity (33% vs. 17%) in women drinking 1 or more sodas per day compared to those drinking less than 1 soda per day (for review, see Malik, 2006).
Benefits of Seltzer Water
Below are some of the benefits that have been found for carbonated water.
- It can help you stay hydrated.
Not all of us like plain, or ‘still’ water. And since it is important to stay hydrated for weight loss, if you like carbonated water better, it can be a good alternative. Studies in fact show that drinking seltzer water made swallowing easier, an effect which lasted up to 60 minutes (Elkishuri, 2016). Other research has noted the thirst quenching effect of both cold and carbonated water, since subjects drank less still, room temperature water afterward (De Gachons et. al, 2016). This has been confirmed in animal studies that show animals prefer to lick cold water and even cold air or metal with no fluids (*Rolls & Rolls, 1982, Michou et. al, 2012).
- It feels good and helps with digestion.
The reaction of the conversion of CO2 (carbon dioxide) stimulates nerves in the mouth that are connected to intestinal (visceral) lining (Dessisier et. al, 2000, Wood et al, 1999, for review see Cuomo et al, 2009). Carbonation acts on smooth muscle and stimulates the movement of the whole gastrointestinal system (Pouderoux et. al, 1997, Zachwieji, 1991, Bellini, 1995, for review see Cuomo et. al, 2002).
- It reduces dyspepsia and constipation.
Dyspepsia, or an upset stomach, is typically characterized by discomfort in the upper abdomen, bloating, belching, and nausea, as well as early satiety (or fullness). Cuomo et. al, 2002 showed significantly lower dyspepsia and constipation scores for participants drinking regular (‘still’) or carbonated water for 15 days. This is one of the most common things we hear from doctors (and moms alike!) helps reduce nausea.
- It improves gallbladder emptying.
The gallbladder stores the salts used for digestion (the bile) and releases them in response to a meal, mostly fats (Baxter, 1985, for review see Marciani et al, 2013). Studies show carbonated mineral water increases the contractions of the gallbladder (Cuomo, 2002), so digestion, especially of fats, is efficient and happens right away.
Patients with constipation often have lower gall bladder volumes and impaired gallbladder responses (Mollen et. al, 2000, Penning et al, 1999). It is important gall bladder emptying occurs, since there is other evidence showing risk of cholesterol gallstones when impaired (Youngsheng et al., 2015, Pauletsky & Paumgartner, 2002, Baxter et al., 1985).
- It helps reduce early satiety in dyspepsia.
Satiety is the feeling typically associated with fullness from a meal and can be impaired in dyspepsic and constipated patients who experience ‘early satiety’ (for review, see Cuomo et. al, 2002). Many assume that because hydration improves weight loss, that we are misinterpreting our food cues to be dehydration, and that drinking more water makes you feel full and eat less calories.
While staying hydrated helps with weight loss (see section on hydration above), there evidence tying it to satiety is mixed. Some studies show carbonated water reduces early satiety for patients suffering from dyspepsia (Cuomo et. al, 2002), and despite increasing gastric volume does not affect food intake after ingesting 300ml of fluid (about 1.25 cups) 3 minutes prior to a meal (Cuomo et al, 2011).
However, other evidence showed that young healthy women given carbonated or regular ‘still’ water first thing in the morning (after a ‘fast’) led feeling of temporary fullness and also increased heart rate Wakisaka et al, 2012. The authors site previous evidence showing increased satiety after ingesting carbonated water through reduced gastric motility (although this evidence was not able to be confirmed), and suggest this could help reduce overeating (for review, see Wakisaka et al, 2012).
In a discussion on the findings on satiety, Cuomo, 2011 cites several studies showing meal size is regulated by a coordinated network of hormones and neural signals in response to digested food (Cummings and Overduin, 2007), and that not just the volume in the stomach, but also the nutrient content, is the key factor in reducing fullness (Powley et. al, 2004, Mackie et. al, 2013).
Any Concerns with Selzer Water?
- It can increase your perceived fluid intake.
While having the effect of quenching thirst, De Gachons et. al, 2016 also showed that carbonated water increased the perceived perception of volume of fluid ingested by 22%, and noted implications for sensitive populations like older adults. Although carbonation decreases early satiety for dyspepsic and constipated patients, evidence suggested above shows it could increase satiety under normal conditions. The obvious concern for weight loss is that drinking something that reduces your satiety could make you eat more.
- Studies show GERD is not a concern when consuming carbonated water.
Gastroesophogeal Disease (GERD) was at one time a concern for those drinking carbonated water, but a systematic review in 2010 of all the available evidence showed there was no increased association and no evidence that carbonated beverages directly cause oesophageal damage or cancer (Cuomo et al, 2011, Johnson et al, 2010).
- For athletes, carbonation can cause a burning sensation and should be consumed in moderation.
Studies show carbonation of 2.3 vol – CO2 or less is best post exercise, and that it can create an increased burning sensation (Passe et al, 1997, for review, see Cuomo et al, 2011).
- The carbonated colas are associated with bone density decline.
Fortunately, only colas, and not other carbonated beverages, are associated with low bone mineral density in older women (*Tucker, 2006, for review, see Cuomo et al, 2009).
- There is some evidence carbonation contributes to tooth decay.
Several studies show carbonated drinks can worsen the already compromised enamel in patients with tooth decay, but note ingredients in the beverage and alteration of saliva as additional factors (for review, see Cuomo et al, 2011). The authors conclude that although studies show the presence of carbonation in beverages can worsen the environment for tooth decay, that it has not been shown not to be a major risk factor for tooth erosion (Holzer, 2011).
- Carbonation causes belching and could stimulate bowl movement.
There is ample evidence, both in the scientific literature and in our everyday experience, that carbonation increases belching (Pouderoux et. al, 1997, Cuomo et. al, 2002, for review, see Cuomo et al, 2011). The carbon dioxide is rapidly released as a gas in the stomach as it is warmed, increasing the pressure and stimulating the gastrus fundus to trigger the belching mechanism (for review, see Cuomo et al, 2011). It has also been associated with lowering constipation scores (Cuomo et. al, 2002) and stimulating sphincter relaxation (Straathoff, 2000). If you are in situations where these things may not be as socially acceptable or bathrooms available, there might be better options.
- It may not always be available, don’t always know quality of water.
Becoming dependent on seltzer water or carbonation to stay hydrated could also be a drawback if you are traveling or in situations where you may not have access to your favorite drinks in a can or bottle, or have your carbonating device in hand. You also may not know the quality of that water or its mineral content, which has also been tied to some of the same benefits as carbonation (Cuomo et. al, 2002).
Main Point
Carbonation has been shown to have benefits for hydration and stimulating digestion. It can exacerbate tooth decay when already present, and may have other minor, temporary side effects. For weight loss, carbonated water can offer some of the hydration and digestion benefits without the harmful effects of colas, but can affect the perceived amount of fluid ingested.
KATY HARRIS, MSPH, CSCS
Katy Harris MSPH, CSCS is a Master of Public Health, Certified Strength & Conditioning Specialist, health and wellness business owner, and ultimate player who runs the WellLife Studio in Chapel Hill, NC.
References:
*Dymchenko, A. A., & Rybak, V. A. (2021). The influence of carbonated beverages on the course of metabolic processes in the body.
“Functional Dyspepsia – Symptoms and Causes – Mayo Clinic.” Mayo Clinic, 29 Dec. 2022.
*Lolli, G., Greenberg, L. A., & Lester, D. (1952). The influence of carbonated water on gastric emptying. New England Journal of Medicine, 246(13), 490-492.
*Reference links not available
