Food Poisoning

Food Poisoning: Overview

Alternative names: Foodborne Illness

Food Poisoning is illness that is caused by eating contaminated food.

Diagnose your symptoms now!
  • let The Analyst™ find what's wrong
  • check your overall health status
  • understand what's happening to your body

Incidence; Causes and Development

Food poisoning is very common, affecting most of us at various times during our lives to some extent.

Hundreds of different toxins and infectious organisms can enter food at any stage, from growing to processing to preparation and cooking.  Infectious organisms such as bacteria (for example Campylobacter, Salmonella, Listeria, Clostridium botulinum or Escherichia coli – E. coli), viruses (for example the norovirus) and parasites, or their toxic wastes, are the most common causes of food poisoning.  Improper handling, storage and/or cooking increases the chance of food becoming contaminated.

Foodborne bacteria become more of a problem as their number increases.  One or two bacteria are not a problem to our digestive system, but several million can be.  The warmer the food, the faster bacteria divide and multiply; refrigeration and freezing slow down or even halt this multiplication.

Bacterial contamination can occur in many ways, including undercooking food, improper cold storage, leaving cooked food out in room temperature for too long, insufficient reheating, food being handled by those who are sick or have dirty hands, food being kept beyond its expiration date, or cross-contamination from nearby foods or shared surfaces.

Most susceptible to bacterial contamination are raw meat, poultry, eggs, seafoods, and milk.

Signs and Symptoms

Symptoms often start within a few hours or within 1-2 days of consuming contaminated food but may start even weeks later.  Symptoms generally last from a few hours to a few days and include:

Diagnosis and Tests

In severe cases where it is important to determine the appropriate antibiotic to prescribe, a stool sample may be analyzed.

Treatment and Prevention

Treatment generally consists of bed rest and drinking plenty of water.  If the patient is hungry, meals should initially be small and light, consisting of bland foods such as rice, bread/toast and bananas.

If dehydration if a problem, especially in the young and elderly, oral rehydration solutions (ORS) are recommended.

Antibiotics may be used, especially if the infection spreads outside the intestines.  Severe cases may require hospital treatment and observation.

Proper food handling, food storage, and personal hygiene are the most important preventative measures.  Hand-washing, cleaning shared surfaces regularly, and not sharing towels are especially important for preventing the spread of infection.

Prognosis; Complications; Seek medical attention if...

Most cases of food poisoning are mild and resolve within a few days without treatment.  Occasionally, severe cases require hospitalization.  Salmonella can on occasion lead to death among the very old, the very young, or those with a weakened immune system.

Recovery from Salmonella infection may take several months and, rarely, leave the patient with a condition known as reactive arthritis that may develop into chronic arthritis.

According to the CDC, some 2-7% of E. coli infections, mainly in the elderly and in children under 5, can lead to Hemolytic Uremic Syndrome which causes destruction of red blood cells and kidney failure.

All forms of botulism can be deadly and are considered medical emergencies.  Left untreated, botulism can lead to paralysis of the arms, legs, trunk, and respiratory muscles.

The following individuals should seek medical attention if food poisoning is suspected:

Those with any of these more serious food poisoning symptoms should also see a doctor:

  • frequent vomiting
  • being unable to keep liquids down
  • diarrhea or other symptoms lasting more than 3-7 days
  • extreme pain or cramps
  • high fever
  • blurred vision or double vision
  • droopy eyelids
  • slowed or slurred speech
  • difficulty swallowing
  • dehydration

    • excessive thirst
    • dry mouth
    • rapid heartbeat
    • little or no urination
    • severe weakness
    • dizziness
    • lightheadedness / confusion
    • sunken eyes
  • neurological symptoms

    • blurry vision
    • muscle weakness
    • tingling

On This Page

Food Poisoning:
Concerned or curious about your health?  Try The Analyst™
Symptom Entry
Symptom Entry
Full Explanations
Optional Doctor Review
Review (optional)


Weak or unproven link: may be a sign or symptom of
Weak or unproven link:
may be a sign or symptom of
Strong or generally accepted link: is often a sign or symptom of
Strong or generally accepted link:
is often a sign or symptom of
We use cookies for traffic analysis, advertising, and to provide the best user experience