Effect of fluid intake on skin physiology: distinct differences between drinking mineral water and tap water

Abstract

It is generally stated that drinking plenty of water has a positive influence on skin condition. However, there is no published scientific study that has investigated this matter. The aim of our exploratory 'before-after' study was to evaluate the in vivo influence of drinking more than 2 L of mineral water or ordinary tap water per day on skin physiology. Ninety-three healthy subjects were included in our prospective study. After an initial run-in phase of 2 weeks to monitor individual drinking habits, subjects had to drink 2.25 L day(-1) of either mineral water (n = 53) or tap water (n = 40) for 4 weeks. Bioengineering in vivo measurements on the volar forearm included sonographic evaluation of skin thickness and density, determination of skin surface pH, assessment of skin surface morphology, and measurement of finger circumference. Eighty-six subjects completed the study. In the mineral water group measurements revealed a statistically significant decrease in skin density. Skin thickness increased slightly, albeit not at a statistically significant level. However, when separately analysing those individuals from the mineral water group, who had routinely drunken comparably little before the start of the study, their skin thickness increased at a statistically significant level. Skin surface pH remained almost unchanged in the physiologically optimal range. In the tap water group, skin density increased significantly, while skin thickness decreased significantly. Skin surface pH decreased at a statistically significant level. While in the mineral water group finger circumference decreased significantly, measurements in the tap water group revealed a statistically significant increase. Objective skin surface morphology did not change in any group. In summary, drinking more than 2 L of water per day can have a significant impact on skin physiology. The exact effects within the skin seem to differ depending on the nature of the water ingested. Randomized, controlled, double-blind follow-up trials are warranted to confirm the findings of our exploratory pilot study.

Effect of Fluid Intake on Hydration Status and Skin Barrier Characteristics in Geriatric Patients: An Explorative Study

“…We are aware of previous studies showing statistical significant associations between fluid intake and pH [11, 30] and SCH [9, 10, 27]. However, the underlying biological mechanisms are unclear and younger healthy populations are not comparable with geriatric patients.…”

Systemic Hydration: Relating Science to Clinical Practice in Vocal Health

“…Water then, plays an integral role in structure and function, with changes in water content necessarily resulting in alterations to performance. Even skin, which has a comparatively low water content of 30%, shows variation in thickness, elasticity and density depending on hydration levels (37). Excess hydration is known to negatively influence the behaviour of the cornea through creation of surface epithelial irregularity and alteration of the tear film-air interface (38).…”

Water and Minerals in the Treatment of Dryness

“…We could not confi rm any objective improvement of wrinkles or skin surface roughness after increasing the daily water uptake to more than 2 liters over weeks" (our underline). In our opinion, the lack of association between excessive fl uid intake and skin surface profi le (e.g., wrinkles, skin surface roughness) as demonstrated in Williams et al's study [ 3 ] provides the main take-home message of the current presentation as well. The lack of any convincing evidence for a benefi t of the 8 × 8 rule in other fi elds also applies to dermatology, including skin wrinkling and surface roughness in otherwise healthy people.…”

“…We are aware of only one study [ 3 ] relating to the effect of long-term water intake (2.25 L/day of either mineral water or tap water) on skin physiology. After 4 weeks of drinking water in excess, the mineral water group measurements revealed a signifi cant decrease in skin density and an increased skin thickness (signifi cantly only in the subjects who routinely drank comparably little before the start of the study).…”