Mild cleansing syndet for daily maintenance of a baby's skin?

The methodology for infant skin cleansing treatment has undergone substantial alterations over the years. In the past, routines encompassed daily soap baths, baby oil applications, and extensive powdering. Gentler soaps and shampoos were deemed safe for infants during the late 1980s; however, current research underscores the benefits of bathing less frequently whilst utilising pH-neutral and mild cleansers to safeguard an already delicate skin barrier. Some specialists even propose that infants should be bathed no more than twice a week, but all concur on the significance of gentle cleansing practices that do not aggravate the skin whilst optimising its health, particularly for those at risk of atopic dermatitis.

Products for cleansing newborns and infants continue to be a topic of discussion. In line with current guidelines, including those given by the British National Institute for Health, the application of cleansers should be centred around gentle, fragrance-free soaps, which ought to be used only when required. A multitude of recent research suggests that cleansing with mild syndet washes is akin to using mere water in preserving the skin's acid mantle and reducing lipid content. For instance, the consistent use of domestic wash gel twice a week during the initial eight weeks of life significantly lowered skin pH across all body areas (pH 5.4 – 5.9, in contrast to the nearly neutral pH 6.2 – 7.5 at birth). A lower pH implies less bacterial proliferation and enzyme activity, which is advantageous for the skin barrier).

A new randomised controlled study assessed the acceptability of a dermatological syndet cleanser on the skin of infants. A cohort of 180 healthy infants were subsequently randomised into three groups of sixty infants. The first group utilised the syndet cleanser, the second an alternative liquid cleanser for babies, and the third tepid tap water as whole-body washes twice weekly for two weeks. Evaluation was conducted at baseline and after one and two weeks using clinical dermatological evaluation, instrumental measurement, and parental report. Key assessed parameters included erythema, oedema, dryness, scaling, skin moisture, surface pH, trans-epidermal water loss, and haemoglobin levels. Results indicated that none of the cleansing modalities caused significant irritation or dryness and no adverse effects were noted, with parents reporting high tolerability for each group. In conclusion, all cleansing methods were effective and safe for infant skin.

Ordinary soaps neutralised with sodium hydroxide typically possess pH values of 10 – 11 or 8.5 – 10 when partially neutralised with gentler alkali amines such as triethanolamine. Combination bars with soap as the primary cleansing agent have an alkaline pH of 8.5–10 and can decrease to 7.5 when soap content is minimal.

Soap-free syndets that are in harmony with the skin's natural pH of 5.5 – 7 do not disrupt its equilibrium—making them appropriate for cosmetic and infant cleansing bars. Medicated bars may possess a low pH of 3.5 – 5 (e.g., iodine-based bars), where acidic conditions guarantee stability. Synthetic detergent-based formulations are optimal for medicated cleansing bars due to their capacity to sustain a stable, low-pH environment.

Another investigation sought to ascertain the pH levels of children's antibacterial soaps and syndets, and verify if such pH levels were denoted on the product labels. The evaluation encompassed a total of 90 soap samples: 67 of these were children's soaps, 17 were antibacterial soaps, and 6 were syndets. The pH levels for liquid soaps fluctuated between 4.4 and 7.9, whilst syndets were the nearest to the ideal slightly acidic range. In contrast, the antibacterial soaps exhibited higher pH levels up to 11.34. Among these, only two soaps indicated pHs on their packaging. The conclusion drawn from this study is that liquid soaps, particularly syndets, are healthier for an infant's delicate skin due to their precise pH levels, which ensure skin health through the barrier.

Daily syndet bathing does not harm the skin, even in instances of compromised barriers with mild redness, hardening, or dryness. Given that infant skin has higher transepidermal water loss (TEWL), increased water desorption rates, and decreased natural moisturising factor (NMF), cleansing agents must be milder than those used for adults to prevent barrier disruption. Although there have been documented cases of irritant contact dermatitis from harsh surfactants, the incidence of irritant reactions to properly formulated products intended for infant use is exceedingly rare (one to three reactions reported for every million units sold). This underscores the importance of selecting a gentle, well-formulated cleansing syndet for baby’s skin. However, more large-scale, standardised studies are required to provide stronger, science-backed recommendations in the future.

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