Food Poisoning: Causes and Natural Solutions

Food poisoning refers to the onset of symptoms following the consumption of contaminated food or drink. This contamination may be caused by bacteria, viruses, parasites, toxins produced by certain micro-organisms or, more rarely, by chemical substances.

The term ‘foodborne infection’ is used when symptoms are linked to the ingestion of food contaminated by a microorganism or by a toxin produced by it. When at least two people develop similar symptoms after consuming the same meal or food, this is referred to as a foodborne outbreak, often abbreviated to TIAC.

Most commonly, the symptoms affect the digestive system: vomiting, diarrhoea, abdominal cramps, nausea. Some cases are brief and mild. Others require special attention, particularly in vulnerable individuals.

Contamination can occur at various stages: production, transport, storage, preparation or consumption. A break in the cold chain, undercooking, poor hand hygiene or cross-contamination between raw and ready-to-eat foods can increase the risk.

Certain bacteria can contaminate food and cause digestive symptoms. Bacteria frequently implicated include Salmonella, Campylobacter, certain strains of Escherichia coli, Listeria monocytogenes and Yersinia.

Contamination can be caused by undercooking, improper storage or cross-contamination between raw and ready-to-eat foods. Cross-contamination refers to the transfer of microorganisms from one food to another, for example via a chopping board, a knife or poorly washed hands.

Certain viruses can be transmitted through food or water. Norovirus is one of the most common causes of foodborne infections. It can cause nausea, vomiting, watery diarrhoea and abdominal pain.

Transmission can occur via contaminated food, a soiled surface or a sick person preparing a meal. This is why hand hygiene and refraining from preparing meals if you have digestive symptoms are essential preventive measures.

Parasites can also be transmitted via contaminated food or water. The risk varies depending on region, dietary habits, travel and hygiene practices.

Some parasitic infections can cause digestive problems that last longer than usual. In the event of persistent diarrhoea, after returning from a trip, or if you experience unusual symptoms, you should seek medical advice.

Certain bacteria produce toxins capable of causing digestive symptoms. In such cases, symptoms may appear quickly after a meal, sometimes within a few hours.

Toxins may be caused by food being left at room temperature for too long, not being chilled sufficiently, or being reheated incorrectly. Maintaining the cold chain and eating prepared meals promptly are therefore useful steps to minimise the risk.

Food poisoning can be caused by simple everyday habits: not washing your hands before cooking, using utensils on raw food and then reusing them on cooked food, a fridge that’s too warm, leftovers kept for too long, or undercooked food.

Micro-organisms do not always alter the smell, appearance or taste of food. A dish may therefore appear normal whilst still posing a risk if it has been stored or prepared incorrectly.

The foods most commonly involved depend on the microorganism responsible, the cooking method, storage conditions and hygiene during preparation. Raw or undercooked foods of animal origin require particular caution: poultry, meat, eggs, dishes containing raw eggs, fish, seafood, raw milk or raw-milk cheeses.

Dishes prepared in advance, leftovers that have been cooled or stored incorrectly, cold meats, ready-made meals, mixed salads, contaminated raw vegetables or food handled after cooking may also be at risk.

The risk therefore stems not only from the food itself, but also from the handling process: storage temperature, waiting time, cooking, handling and the separation of raw and cooked foods.

The term ‘indigestion’ is often used in everyday language to describe digestive discomfort after a meal. It does not exactly correspond to food poisoning. Simple indigestion may be linked to a meal that is too large or poorly tolerated, whereas food poisoning involves food contaminated by a microorganism, a toxin or a substance.

The duration depends on the cause. Some mild forms of food poisoning improve within a few hours to a few days. Others may last longer, depending in particular on the causative agent, the amount ingested, age, general health and the risk of dehydration.

Persistent diarrhoea, repeated vomiting, a fever, blood in the stools, signs of dehydration or severe fatigue should prompt you to seek medical advice. Duration alone is not always sufficient to assess the situation: the context and associated symptoms are very important.

You should seek medical advice if symptoms are severe, persistent or accompanied by unusual signs. Severe or prolonged diarrhoea, repeated vomiting, a high fever, blood in the stools, severe abdominal pain or extreme fatigue are all reasons to seek medical advice.

Signs of dehydration also require particular attention: intense thirst, a dry mouth, infrequent or dark urine, dizziness, drowsiness, malaise or marked weakness. In the case of a child, an elderly person, a pregnant woman, or someone who is immunocompromised or suffering from a chronic illness, medical advice should be sought more readily.

A consultation is also necessary if several people experience the same symptoms after sharing a meal. This may indicate a collective case of food poisoning. The healthcare professional will be able to advise on the appropriate course of action depending on the circumstances.

Food poisoning should not be dismissed as mere digestive discomfort when symptoms are severe. The priority is to prevent dehydration, especially in the event of repeated vomiting or diarrhoea.

Natural remedies are no substitute for medical advice if warning signs are present. They do not enable the causative agent to be identified, nor do they rule out the possibility of a more severe form of the condition.

Anti-diarrhoea, anti-emetic or anti-inflammatory medicines should not be taken routinely without professional advice. Their suitability depends on the circumstances, age, associated symptoms and general state of health.

In the event of pregnancy, immunosuppression, chronic illness, high fever, blood in the stools, persistent diarrhoea or repeated vomiting, seek advice promptly.