RT Book, Section
A1 Baumann, Leslie
SR Print(0)
ID 1174541772
T1 Humectants
T2 Cosmeceuticals and Cosmetic Ingredients
YR 2015
FD 2015
PB McGraw-Hill Education
PP New York, NY
SN 9780071793988
LK dermatology.mhmedical.com/content.aspx?aid=1174541772
RD 2024/04/19
AB Humectants  are  water-soluble  materials  with  high  water  absorption  capabilities.  They  are  hygroscopic  and  therefore  able  to  attract  water  from  the  atmosphere  (if  atmospheric  humidity  is  greater  than  80  percent)  and  from  the  underlying  epidermis.  Although  humectants  may  draw  water  from  the  environment  to  help  hydrate  the  skin,  in  low-humidity  conditions  they  may  take  water  from  the  deeper  epidermis  and  dermis,  resulting  in  increased  skin  dryness.1  For  this  reason,  they  work  better  when  combined  with  occlusives.  Humectants  are  also  popular  additives  to  cosmetic  moisturizers  for  many  reasons.  They  prevent  product  evaporation  and  thickening,  which  increases  the  shelf  life  of  formulations,  and  some  humectants  help  prevent  bacterial  growth  in  products.2  Humectants  can  cause  an  almost  immediate  improvement  in  skin  texture  because  they  draw  water  into  the  skin,  causing  a  slight  swelling  of  the  stratum  corneum  (SC)  that  gives  the  perception  of  smoother  skin  with  fewer  wrinkles.  Humectants,  by  inducing  swelling,  can  temporarily  give  the  user  the  perception  of  increased  skin  firmness.  Humectants  have  been  shown  to  enhance  the  penetration  of  other  ingredients  by  causing  swelling  of  keratinocytes,3  and  disruption  of  the  skin  barrier  by  loosening  the  closely  packed  SC  cells.4  Propylene  glycol  enhances  penetration  of  minoxidil  and  steroids,5  while  hyaluronic  acid  increases  drug  delivery  in  prescription  medications  such  as  Diclofenac.4  Examples  of  commonly  used  humectants  include  glycerin,  sorbitol,  sodium  hyaluronate  (hyaluronic  acid),  urea,  propylene  glycol,  α-hydroxy  acids,  and  sugars.