Why Do People with Diabetes Experience Dry Mouth?

People with diabetes experience symptoms that negatively influence their quality of life. One of them is dry mouth. We explain why it happens.
Why Do People with Diabetes Experience Dry Mouth?
Leonardo Biolatto

Written and verified by the doctor Leonardo Biolatto.

Last update: 27 May, 2022

People with diabetes, whether type 1 or type 2, often experience dry mouth, or xerostomia. The problem is that it’s not just a sensation; it can have serious consequences at an oral level.

Xerostomia is associated with an increased risk of caries, infections, and periodontal disease. Different investigations affirm that more than 70% of people with diabetes experience dry mouth. Therefore, in this article, we’ll explain why it happens and how to solve it.

What are the symptoms of diabetes?

Diabetes mellitus is a disease that affects the metabolism of glucose. There are two main forms: type 1 and type 2. In the case of type 1 diabetes, what happens is that the pancreas is unable to secrete insulin.

On the other hand, in type 2, there’s a resistance to insulin in the different tissues of the body. However, there may also be a decrease in its secretion. This is a pathology that, unfortunately, is becoming more and more frequent.

Xerostomia is one of the main symptoms of diabetes. So much so that, according to a review study published in the Journal of Endocrinology and Nutrition, it’s among the most frequent oral manifestations in people with diabetes.

Other oral symptoms that can appear are ulcers, pharyngeal candidiasis, and a burning sensation. However, these aren’t the only signs. There’s also polyuria (increased urination), polydipsia (increased thirst), and weight changes.

A man with diabetes measures his glucose.
Blood glucose values are the determinants of symptoms in diabetes.

Why do people with diabetes experience dry mouth?

Xerostomia, as we’ve mentioned, is the term that refers to dry mouth. In people with diabetes, its appearance has to do with different factors, almost all related to poor blood sugar control.

First of all, one of the causes is increased urination. An increase in urination leads to dehydration. And, since saliva is composed mostly of water, its production becomes altered when body fluids are misaligned.

Another similar factor that determines dry mouth in diabetes is a change in the composition of saliva. In addition to water, saliva also contains glucose and protein.

A study published in the Journal of Oral Medicine and Pathology explains that diabetes affects the morphology of the salivary glands. It produces the so-called diabetic sialosis, which consists of the salivary glands increasing in size. This causes their functioning to be impaired.

Other causes of xerostomia

Although a large percentage of people with diabetes experience dry mouth, this disease isn’t the only cause. It’s important to note that many factors influence the production of saliva and many situations can trigger xerostomia.

For example, non-diabetes related dehydration. Similarly, medications can give rise to this symptom, especially those used in chemotherapy treatments.

Older age is also often a factor, as are other chronic diseases such as cirrhosis, HIV, and tuberculosis. Sjögren’s syndrome is another of the most relevant causes of xerostomia.

Dry mouth solutions for people with diabetes

The importance of dry mouth in diabetes lies not only in the discomfort it produces but also in the series of oral problems it can produce. For example, it increases the risk of suffering from cavities and infections, as well as periodontal disease.

Therefore, it’s essential to carry out preventive measures that avoid and prevent this type of pathology. First of all, people with diabetes must reinforce their oral hygiene by using mouthwashes and dental floss, in addition to brushing.

Furthermore, it’s best to avoid sugary and acidic liquids. Of course, staying hydrated is essential, but it’s best to do so by drinking water. Frequent visits to the dentist are also necessary since the professional must check and correct any alteration as soon as possible.

In addition, in some cases, doctors prescribe medications that stimulate salivary flow. In fact, they may even use artificial saliva. Of course, these measures are reserved for cases in which general measures fail to solve xerostomia.

Oral hygiene is fundamental in reducing the risks associated with xerostomia.

To remember

People with diabetes are more prone to experiencing dry mouth. This is because the disease changes both the composition of saliva and the morphology of the salivary glands.

In order to avoid this, it’s necessary to maintain proper control of blood sugar levels. In addition, correct hydration and special care with oral hygiene are essential requirements in order to reduce complications.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • Molania, T., Alimohammadi, M., Akha, O., Mousavi, J., Razvini, R., & Salehi, M. (2017). The effect of xerostomia and hyposalivation on the quality of life of patients with type II diabetes mellitus. Electronic Physician, 9(11), 5814–5819. https://doi.org/10.19082/5814
  • Escobar, Deyanira Cabrera, Luis González Valdés, and Orquídea Ferrer Hurtado. “Xerostomía en pacientes con síndrome de Sjögren.” Revista Electrónica Dr. Zoilo E. Marinello Vidaurreta 42.1 (2017).
  • Hoseini, A., Mirzapour, A., Bijani, A., & Shirzad, A. (2017). Salivary flow rate and xerostomia in patients with type I and II diabetes mellitus. Electronic Physician, 9(9), 5244–5249. https://doi.org/10.19082/5244
  • Navea Aguilera, C., Guijarro de Armas, M. G., Monereo Megías, S., Merino Viveros, M., & Torán Ranero, C. (2015, January 1). Relación entre xerostomía y diabetes mellitus: Una complicación poco conocida. Endocrinologia y Nutricion. Elsevier Doyma. https://doi.org/10.1016/j.endonu.2014.09.004
  • Xerostomía: Diagnóstico y Manejo Clínico. (n.d.). Retrieved August 29, 2020, from http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S1699-695X2009000100009
  • López-Pintor, R. M., Casañas, E., González-Serrano, J., Serrano, J., Ramírez, L., De Arriba, L., & Hernández, G. (2016). Xerostomia, Hyposalivation, and Salivary Flow in Diabetes Patients. Journal of Diabetes Research. Hindawi Limited. https://doi.org/10.1155/2016/4372852
  • García Chías, Begoña. Prevalencia de los efectos orales secundarios a la quimioterapia en un hospital de Madrid y factores asociados. Diss. Universidad Complutense de Madrid, 2019.
  • MANEJO TERAPEÚTICO DEL PACIENTE CON XEROSTOMÍA. (n.d.). Retrieved August 29, 2020, from https://www.actaodontologica.com/ediciones/2001/1/manejo_terapeutico_paciente_xerostomia.asp
  • Ivanovski, K., et al. “Xerostomia and salivary levels of glucose and urea in patients with diabetes.” Contributions of Macedonian Academy of Sciences & Arts 33.2 (2012).

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.