Water UK

Saliva

Saliva is essential for the maintenance of oral health. Dehydration decreases saliva flow rates and leads to changes in saliva composition, including increased osmolality and protein concentration.(1,2,3)

Saliva is important for good oral health because it neutralises the acid created by the bacteria which cause tooth decay, physically washes teeth, lubricates oral membranes, contains minerals that enable tooth repair (remineralisation) to occur, contains antibacterial agents that can inhibit the proliferation of oral bacteria and prevent gum disease, and contains the enzyme amylase, which begins the digestion of starch.
The protective role of saliva in dental disease and the link between saliva and dehydration have been confirmed. Unfortunately, although there is considerable circumstantial evidence to indicate that mild dehydration may be a risk factor for dental disease, to date, this link is not directly proven. In view of the potential benefits of adequate hydration for dental disease, further research is recommended.(4,5)

Last updated: December 2006

(1) Ship JA, Fischer DJ. The relationship between dehydration and parotid salivary gland function in young and older healthy adults. J Gerontol 1997;52A:M310-M319
(2) Fischer D, Ship JA. The effect of dehydration on parotid salivary gland function. Special Care in Dentistry 1997;17:58-64
(3) Walsh NP, Montague JC, Callow N, Rowlands AV. Saliva flow rate, total protein concentration and osmolality as potential markers for whole body hydration status during progressive acute dehydration in humans. Arch Oral Biol 2004;49:149-154
(4) Smith AJ and Shaw L. Mild dehydration: a risk factor for dental disease? Eur J Clin Nutr 2003;57(Suppl 2):S75-80
(5) Manz F and Wentz A. The importance of good hydration for the prevention of chronic diseases. Nutr Rev 2005;63:S2-S5