The slightly acidic nature of carbonated water makes it a great candidate for improving barrier function and overall skin stability.
Carbonated water is produced by enrichment of regular water with carbon dioxide. This infusion produces the bubbles that we often enjoy in fizzy drinks and reduces the water’s pH level to around 5 (depending on the amount of carbonate dioxide infused into the water).
In comparison, regular tap water commonly has a pH in the range of 6-8 (often reported in the upper part of this range) .
Due to it’s acidic nature and long history of beneficial reports for a variety of skin ailments, researchers decided to investigate the impact of carbonated water application to the skin.
The result of this investigation revealed that regular rinsing of the skin with carbonated water can beneficially influence the skin surface pH [2, 3]. And this increased pH was presumed to be primarily responsible for the variety of beneficial secondary effects on skin integrity (as compared to regular tap water).
Even Regular Tap Water Can Raise Skin Surface pH
Investigation into the effect of skin washing on skin surface pH has shown that washing with even water alone can have a significant influence on the skin surface pH level (increasing it’s pH) . This increases in skin surface pH may result in a variety of unfavorable consequences for the skin .
The most apparent effects noted in the studies above, include:
- Improved skin pH balance
- Decreased transepidermal water loss (TEWL)
- Improved stratum corneum lipid availability
- Accelerated clearing time of irritation
- Higher stratum corneum lipid and ceramides content
- Overall improvement of barrier function
In addition to these two papers, other researches have noted similar effects can be derived from naturally acidic mineral water:
- Repeated application of acidic spring water can produced significant prolonged reduction in skin surface pH and inhibit bacterial growth 
- Bathing in acidic hot springs improved symptoms of atopic dermatitis, with marked reduction in staphylococcus aureus on the skin surface 
Why It’s Important for Inflammatory Skin Disease
Characteristics most important for individuals affected by inflammatory skin disorders:
- Improved barrier function
- Improved sebum composition
- Reduced irritation to environmental factors
- Reduced skin dryness and flaking
- Reduced sensitivity
- Producing carbonated water at home (with a soda maker) can reduce associated costs and allows the user to manually increase carbon oxide content (further lowering the pH)
- The skin itself has four main methods of buffering it’s pH (lactic acid/lactate system, free amino acids, proteins, and carbon dioxide/bicarbonate system  and using carbonated water is a simple way to influence one the skin’s own systems