Published on February 13, 2019 at 13:16 / Updated on June 7, 2022 at 13:09

Gastroenteritis is an infection of the digestive tract caused by a bacteria, virus or parasite. Besides diarrhea and vomiting, there can also be fever and abdominal pain. These symptoms are usually short-lived and can sometimes be very bothersome. If precautions aren’t taken, these often cause a state of dehydration as well as a disturbance in the level of electrolytes and acid-base balance. In the event of prolonged episodes of diarrhea, a state of malnutrition may also develop. Here’s an overview of the nutritional treatment for gastroenteritis!

The nutritional approach

The nutritional approach to gastroenteritis aims to correct dehydration and restore the acid-base balance, as well as to ensure proper hydration to maintain an optimal nutritional state.


Oral rehydration remains the primary treatment. This is much less expensive than the intravenous treatment used for severe dehydration. The oral rehydration solution consists of an optimal amount of water, glucose and electrolytes to replace losses caused by vomiting and/or diarrhea. According to the World Health Organization, the optimal glucose: sodium ratio should be: 1.4: 1. Adhering to the ratio is important since too much glucose will cause osmotic diarrhea and not enough glucose will slow down the rehydration process. Some commercial solutions are specially designed to meet these criteria, such as Pedialyte™ or Gastrolyte™.

In order to decrease fluid loss through diarrhea, using a formula based on rice starch rather than glucose can significantly reduce the amount of stool. However, the literature is controversial on this subject and there aren’t many products available on pharmacy shelves.

Practical advice about oral rehydration solutions

  • The solution shouldn’t be diluted with juice as the glucose: sodium ratio would also be altered and therefore suboptimal. 
  • In the presence of vomiting, oral rehydration solution is used successfully and helps reduce vomiting. Tolerance improves when the solution is administered in small but frequent amounts.
  • The following alternatives are not recommended as a replacement for oral rehydration solution: rice water, homemade solutions, fruit juices, soft drinks, broths, store-bought soups, sports drinks.

Hydration maintenance phase

After the rehydration phase, i.e. no later than 12 hours after the start of the rehydration solution, other fluids, such as water, milk and sugar-free juice, can be added to the diet to ensure a higher fluid intake than usual.

Adequate diet

Resuming food intake or continuing to feed has a multitude of benefits including decreased symptom duration, protecting/rebuilding the intestinal lining after fasting or infection, preventing an increase in the permeability of the intestinal lining, improving nutritional status and preventing malnutrition.

Practical advice about reintroducing food during or after gastroenteritis

  • Reintroduce solid food with small, frequent, well-balanced meals that are high in energy and easy to digest.
  • There’s no specific order for reintroducing solid foods. Individual tolerance varies from individual to individual.
  • Foods containing starch seem to be easily tolerated and can help decrease the volume and quantity of stools. Opt for rice, wheat, potatoes, bread and cereals, as well as lean meats, yogurt, fruits and vegetables. 
  • Some foods high in simple sugars should be avoided until the diarrhea has stopped because of their high osmotic pressure, which could exacerbate the diarrhea. Avoid sugary juices, fruit-flavored jellies, jams, sodas, etc.
  • Foods very high in fat can be poorly-tolerated since they delay the passage of food from the stomach to the small intestine. 
  • Don’t be alarmed if the number of stools increases following the reintroduction of food. The normal appearance and quantity of stool will return after 7-10 days.
  • Probiotics don’t seem to have any effect if taken during episodes of gastroenteritis. However, traveler's diarrhea can be prevented by taking certain strains of probiotics before a trip.

Finally, the nutritional treatment of gastroenteritis focuses on correcting or maintaining adequate hydration, then reintroducing food gradually in order to maintain an adequate nutritional status without exacerbating the symptoms. The above recommendations apply to adults only. For infants and young children, it may be helpful to consult a nutritionist or healthcare professional to determine an appropriate nutritional treatment. 

Familiprix in collaboration with Hubert Cormier

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