Checklist: 5 Foods to Avoid in Summer to Prevent Diarrhea and Food Poisoning

A collection of dangerous summer dishes to avoid, along with tips on storing food safely using the 2-hour rule to prevent diarrhea and food poisoning.

As summer arrives and temperatures rise, it's important to be cautious not only about sun exposure but also about food safety. Hot weather encourages rapid growth of microorganisms and bacteria, causing food to spoil more quickly than usual. Here is a checklist of foods to avoid and tips for safe food storage to keep you free from diarrhea and food poisoning throughout the summer.

Five types of food to avoid and be especially cautious of during summer.

During extreme heat, certain foods have a high risk of contamination. Poor storage or insufficient cooking can easily harm your health as follows.

1. Foods containing coconut milk.

Green curry, red curry, or Thai desserts with coconut milk are among the top dishes that spoil fastest in hot weather. Leaving them at room temperature for just a few hours allows bacteria to start multiplying immediately.

2. Seafood and undercooked dishes.

Popular dishes like shrimp in fish sauce, spicy cockle salad, or raw blood salad carry a risk of Vibrio bacteria if ingredients are not fresh or thoroughly cleaned. This is a leading cause of severe diarrhea.

3. Dishes containing raw eggs.

Some salad dressings or dishes using raw eggs risk Salmonella infection, which thrives in hot conditions, causing nausea, vomiting, and stomach pain.

4. Leftover food not reheated thoroughly.

Reheating leftovers insufficiently—below 70 degrees Celsius—may fail to kill bacteria that developed during the day.

5. Fresh vegetables that are not properly washed.

Many overlook fresh vegetables in dishes like papaya salad or mixed rice. Vegetables watered with unclean water or not washed well can carry parasite eggs or bacteria.

Tips for "storing food" to keep it safe from germs.

Cooking alone is not enough. Improper storage can turn seemingly clean food into a breeding ground for germs in no time. Here are recommended practices.

• The golden rule: "2 hours." Under normal conditions, cooked food should not be left out for more than 2 hours. In Thailand’s summer, with temperatures exceeding 32 degrees Celsius, this time should be reduced to just 1 hour before refrigerating immediately.
• Don’t wait for food to cool completely and become damp: Once food has stopped steaming (around 60 degrees Celsius), it can be put in the fridge. Leaving it out too long allows moisture to create an ideal environment for germs.
• Divide into smaller containers to cool faster: For large pots of food, it’s best to divide into small, shallow containers so the food cools quickly and evenly in the fridge.
• Organize the refrigerator to prevent contamination: Always store cooked food on the top shelf and raw meat on the bottom shelf to prevent meat juices from dripping onto other foods.

How to recognize "food poisoning" symptoms and first aid.

If you consume contaminated food, symptoms usually appear within 2-6 hours. Warning signs include:

• Severe abdominal cramps and frequent diarrhea.
• Nausea and intense vomiting.
• Fever or headache accompanying the symptoms.

Basic care: Drink oral rehydration salts (ORS) to replenish fluids lost, avoid anti-diarrhea medication to allow the body to expel toxins, and seek medical attention immediately if symptoms worsen within 24 hours or if lethargy occurs.

How to eat safely during summer.

The key is the "cook, hot, clean" principle: eat freshly cooked food, reheat market-bought food thoroughly before eating, and wash hands often. With these practices, you can enjoy summer without worrying about your health.