Understanding Dehydration and Its Link to Nausea
What is dehydration?
Dehydration is a condition in which the body lacks water and essential minerals such as sodium and potassium, which are necessary for the body's proper functioning. On average, water accounts for about 60% of an adult's body weight. This liquid is involved in many physiological functions such as the transport of nutrients, the elimination of waste, and the regulation of body temperature. When water intake does not compensate for losses (perspiration, urine, vomiting, other occasions favoring dehydration, etc.), an imbalance occurs, exposing the body to more or less serious disorders.
What can cause nausea?
Nausea results from the activation of an area of the brain, often in response to digestive problems, infections, or ingestion of irritating substances. When dehydration occurs, the decrease in blood volume and the alteration of electrolyte balance can disrupt the digestive system and the brain, thus promoting the appearance of nausea. Vomiting aggravates the loss of water and minerals, creating a vicious cycle between dehydration and nausea. Nausea can also be caused by fatigue, digestive disorders, benign illnesses such as gastroenteritis, or more serious illnesses such as meningitis.
Symptoms of Dehydration and Nausea
What are the first signs of dehydration?
The first signs of dehydration are generally a feeling of thirst, dry lips, unusual fatigue, headaches and nausea. Other more serious symptoms may appear: dark and less abundant urine, dry skin, dizziness, confusion or even behavioral disorders. In case of severe dehydration, blood pressure can drop, leading to vertigo.
Age-specific symptoms
Dehydration manifests differently depending on age. Children and the elderly are particularly at risk due to their physiological fragility.
In infants, water loss can be very rapid. Observable symptoms of dehydration include a sunken fontanelle (soft spot on the skull), tearless crying, irritability, and rapid breathing. In very young children, this rapid water loss can lead to a weight loss of 10 to 15%.
In the elderly, dehydration can manifest as dark urine, dizziness, loss of appetite, and unusual fatigue. These individuals are particularly at risk because their sensation of thirst is not pronounced, which reduces proper hydration reflexes and can worsen dehydration. It is crucial to pay even more attention to these vulnerable individuals and continue prevention efforts regarding the risks of dehydration for our seniors.
How to differentiate nausea related to dehydration from other causes?
To differentiate nausea related to dehydration from nausea of another origin, it is necessary to identify and analyze the symptoms associated with the nausea and the context in which it occurs. Nausea due to dehydration is often accompanied by specific signs such as intense thirst, a dry mouth, a decrease in urine volume (which becomes darker), unusual fatigue, dizziness, or fever. It frequently occurs after excessive sweating, vomiting, diarrhea, or insufficient water intake. Conversely, if nausea is accompanied by fever, intense abdominal pain, acute diarrhea, during an additional medical treatment, or during infections, another cause is likely.
The main causes of dehydration
Dehydration results from an imbalance between fluid intake and loss. Insufficient water consumption is often the cause of fluid deficit, but other causes can lead to dehydration. Excessive sweating, caused for example by high heat or intense physical activity, vomiting or diarrhea, causes the body to excrete water and mineral salts, leading to a lack of body hydration. Certain chronic diseases (diabetes, kidney failure), age, fever, prolonged sun exposure or alcohol consumption increase water and mineral loss and therefore worsen cases of dehydration.
Solutions for reacting to dehydration and nausea
How to rehydrate quickly?
To compensate for dehydration, it is essential to drink both water and reintroduce electrolytes (sodium, potassium, magnesium, etc.) into your body. Oral rehydration solutions (ORS), available in pharmacies, are particularly effective because they contain the right balance of water, glucose, and electrolytes necessary for the body. Drinking water remains a basic option, but in case of significant losses (stomach flu, vomiting, diarrhea), it is recommended to favor ORS. In case of fluid deficit, it is important to avoid alcoholic or caffeinated beverages, which increase urinary excretion and thus prevent proper body hydration. In general, alcoholic beverages should be consumed in moderation. Excessive alcohol consumption is dangerous for health.
What to drink when feeling nauseous?
When feeling nauseous, certain foods can help relieve symptoms. Ginger and mint are known for their soothing properties and aid digestion. They can be consumed as infusions or herbal teas. It is also essential to maintain good hydration. Prioritizing water and mild beverages, in small but frequent amounts, helps prevent dehydration. Clear broths, such as vegetable broth, are recommended because they provide essential minerals while being easy to digest.
How to hydrate when you have nausea?
If you're feeling nauseous, it's recommended to drink in small sips, regularly, rather than large quantities, to avoid overloading your stomach. You can also eat water-rich foods such as watermelon, cucumber, oranges, or soups to help your body rehydrate properly.
When to consult a doctor?
You should consult a doctor quickly if dehydration worsens. Alarming signs include confusion, loss of consciousness, persistent vomiting preventing any hydration, high fever, or, in infants, a sunken fontanelle or crying without tears. Elderly people and those with chronic illnesses should also be closely monitored. Various treatments can then be recommended by the doctor to help the body rehydrate.
Preventing dehydration and nausea
To prevent the risks of dehydration and nausea, it is advisable to adopt a hydration routine adapted to your daily needs. Regularly drinking the recommended amount of water (at least 1.5 L to 2 L for an adult) is necessary, to be adjusted according to age, physical activity, and climatic conditions. Hydration products containing electrolytes, essential minerals for the proper functioning of the body, can be integrated into the routine to optimize fluid balance during exertion or intense heat. To supplement fluid intake, water-rich foods (fruits, vegetables, soups) can be considered.
Bibliography
Duggan, C., Refat, M., Hashem, M., Wolff, M., Fayad, I., & Santosham, M. (1996). How valid are clinical signs of dehydration in infants?. Journal of pediatric gastroenterology and nutrition, 22(1), 56–61. https://doi.org/10.1097/00005176-199601000-00009
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