Folks living with eating disorders, particularly Anorexia Nervosa and Bulimia Nervosa, are at a higher risk of dehydration. Severe dehydration can be very dangerous and must be taken seriously.
Signs of dehydration in your child may include:
- Thirst
- Dark-coloured urine
- Infrequent urination
- Dizziness
- Lightheadedness
Health Concerns Related to Dehydration
Severe dehydration can cause heart problems such as low blood pressure and a rapid pulse. It can also cause your child to fall unconscious. If your child is severely dehydrated, they may require hospitalization.

Dehydration and Anorexia
Anorexia Nervosa (AN) is classified in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) as an eating disorder. Folks living with AN severely restrict their food intake which can lead to malnutrition.
We obtain fluids not only from drinking beverages but also from eating solid foods. This is because solid foods also contain water that our bodies can absorb. Therefore, if your child is severely restricting their food intake, they may have a lower fluid intake. This can lead to dehydration.
Dehydration and Bulimia
Bulimia Nervosa (BN) is an eating disorder that is also diagnosed based upon the criteria listed in the DSM-5. Folks living with BN engage in binge episodes and compensatory behaviours (purging).
Examples of compensatory behaviours include self-induced vomiting, fasting, excessive exercise and laxative or diuretic misuse. Some compensatory behaviours can cause your child to become dehydrated, especially if your child engages in them multiple times a day.
Dehydration and Self-Induced Vomiting
If your child is engaging in self-induced vomiting, they’re expelling both food and fluids. This loss of fluid can cause your child to become dehydrated.
Dehydration and Laxatives and Diuretics
Laxatives cause folks to have a bowel movement. Bowel movements that are stimulated by laxatives are mainly water, electrolytes and minerals. Therefore, if your child is misusing laxatives, they may have chronic watery diarrhea. The loss of water from your child’s stool can lead to dehydration.
Diuretics cause the body to get rid of excess water through the urine. Similar to laxatives, this loss of water can lead to dehydration.
Eating Disorders and Drinking Too Much Water
Yes, eating disorder behaviours can cause folks to become dehydrated. However, it is important to note that folks living with eating disorders may also consume an excessive amount of fluids. Your child may drink an excessive amount of water as an alternative to consuming food. Some folks may also consume high amounts of caffeinated drinks to increase their energy levels without eating food.
Signs of overhydration in your child may include:
- Clear urine
- Nausea
- Vomiting
- Seizures
- Confusion
Similar to dehydration, overhydration is dangerous and must be taken seriously.
How to Help Your Child
If your child is engaging in compensatory behaviours, be mindful and look for signs of dehydration. Make sure to also be aware that your child may be consuming excessive amounts of fluids to compensate for their low caloric intake.
Remember, early intervention gives folks the best chance at recovery. Our team is here to help you and your child navigate eating disorder recovery. If you’re interested in learning more about how we can help, you can book a free consultation call with us.
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