You should avoid raw or undercooked seafood, unpeeled street fruits, and anything made with tap water or crushed ice in Thailand. These can carry bacteria that might upset your stomach. Even if locals eat them with no problem, your body might not handle them the same way.
Stay away from dishes with raw blood or strong fermented fish paste, especially if you’re not used to them. They can taste very strong and sometimes carry health risks if not prepared safely. Also, skip food that’s been sitting in the heat for too long, like skewers left out on a cart.
Fried snacks are tasty, but make sure they’re cooked in clean oil. Old, reused oil can make food greasy and unhealthy. If the vendor’s stall looks dirty or the food smells off, walk away.
It’s also good to avoid anything made from endangered animals, like shark fin. Some dishes are part of religious offerings, so don’t eat food placed near temples.
Thailand has tons of amazing food, but knowing what not to eat helps you stay healthy and enjoy your trip. Stick with busy stalls, cooked food, and sealed water bottles. When in doubt, ask a local or just go with your gut.
Thai Food | Why Thai people are not fat
Thailand is a food lover’s paradise, but not everything is safe or smart to eat. According to the WHO, over 30% of travelers to Southeast Asia experience foodborne illness, often from poor hygiene or unfamiliar ingredients. I’ve traveled Thailand top to bottom, and trust me, a few dishes sent me running (literally).
In this guide, I’ll walk you through the must-know “don’t eats” in Thailand, from risky street snacks to foods considered disrespectful to consume. If you want to enjoy Thai cuisine without regrets, read this before your first bite!
Raw or Undercooked Seafood in Street Markets
When you visit Thailand, it’s super tempting to try fresh seafood from busy street markets. The grilled shrimp, oysters, and sushi-like dishes look amazing. But eating raw or undercooked seafood in Thailand can be risky, especially if you’re not used to it. Some seafood might not be kept cold enough, and if it’s been sitting out in the heat, bacteria can grow fast. Your stomach might not handle it well, even if the locals seem fine eating it.
I once tried a raw prawn salad from a night market in Bangkok. It looked fresh, and the vendor smiled and said, “Very good!” But two hours later, I was curled up in my hotel room with stomach cramps and a long night ahead. Trust me, it’s not worth the risk.
If you’re craving seafood, go for dishes that are fully cooked, like grilled squid or stir-fried prawns. Hot food is safer because the heat kills germs. And make sure the stall is clean and busy, that usually means the food hasn’t been sitting around too long. Stay smart, and you can still enjoy amazing seafood in Thailand without getting sick.
Unpeeled Fruits Sold on the Street
Thailand has some of the most delicious fruits in the world. Mangoes, papayas, pineapples, they’re everywhere, and they’re super cheap. But if you see cut-up fruit sitting out on a cart, especially without a cover, be careful. A lot of the time, that fruit was washed in tap water or handled without gloves. That means germs can get on it, and you might end up with an upset stomach.
I learned this the hard way in Chiang Mai. I bought a cup of watermelon from a street vendor. It was hot out, and the fruit looked juicy and cold. A few hours later, I wasn’t feeling great. It wasn’t awful, but I definitely spent more time near a bathroom than I wanted to that day.
If you want to stay safe, buy whole fruit and peel it yourself. Bananas, mangosteens, and rambutans are perfect for that. Even mangoes are safer when you get them whole and peel the skin. If you really want pre-cut fruit, look for a busy stand where everything is kept on ice and covered. That usually means it’s fresher and cleaner.
Tap Water and Ice Cubes
One of the biggest mistakes tourists make in Thailand is drinking the tap water. It might seem fine at first, clear and cool, but it’s not treated the same way as it is in many Western countries. It can carry bacteria that your body isn’t used to, and that can lead to stomach problems fast. Even brushing your teeth with tap water can be risky for some people.
But here’s the sneaky part: ice. A lot of drinks at street stalls come with ice, and not all ice is safe. Crushed ice is often made from tap water, which means it could carry the same bacteria. On the other hand, tube-shaped ice (the kind with a hole in the middle) is usually factory-made and considered safe because it’s filtered and clean.
When I first arrived in Thailand, I ordered a sweet Thai tea from a small shop on the sidewalk. It was packed with crushed ice. I didn’t even think about it, just drank it all. That night, I felt awful and couldn’t eat anything for the next day. After that, I always checked the shape of the ice before drinking.
Stick to bottled water, sealed ones, not refilled ones. And skip the ice unless you know it’s the safe kind. A little caution goes a long way.
“Mystery Meat” Dishes or Meat Left in the Heat
In Thailand, you’ll see tons of grilled meat on skewers, sizzling away on open grills. It smells amazing, and it’s super cheap. But sometimes, you don’t really know what kind of meat you’re eating. It could be pork, chicken, beef, or something less familiar. And if that meat has been sitting out in the sun or not cooked all the way through, it can be risky.
I once bought a skewer from a quiet vendor because the smell was just too good to resist. The meat looked a little dark and dry, but I figured it was just well-cooked. I never found out exactly what kind of meat it was, but a few hours later, I definitely regretted eating it. I felt dizzy, nauseous, and couldn’t eat anything else that day.
The key is to stick with busy stalls where the meat is being grilled fresh right in front of you. If the skewers are just sitting out in the open, especially in the heat, walk away. Meat spoils fast in hot weather. Also, watch how clean the grill looks and whether the vendor is handling food with care.
Fresh, hot, and crowded usually means the food is safe. Anything else? It’s a gamble.
Dishes with Raw Blood or Fermented Fish Paste
Thailand has some bold and unique flavors, but a few traditional dishes can really surprise you in ways your stomach might not like. Some local recipes include raw pig’s blood or strong fermented fish paste. These are loved by many locals but can be too much for tourists, especially when you’re not used to them. Raw blood, for example, can carry harmful bacteria and parasites. And fermented fish paste has a super strong smell and taste that can turn your stomach if you’re not ready for it.
I remember trying a dish called “Larb Lueat.” It looked like regular larb (a tasty minced meat salad), but it was soaked in raw blood instead of lime juice. I took one bite, and wow, it was metallic, sour, and just too much for me. I didn’t get sick, but my stomach was upset for the rest of the day. It’s definitely not something I’d try again.
Fermented fish paste, or “pla ra,” is another one to be careful with. It’s used in some versions of som tam (papaya salad), and while locals love the rich, funky flavor, it can hit your system hard. If you’re trying som tam, you can always ask for it without fermented fish, just say “mai sai pla ra.”
Trying new food is part of the fun, but you don’t have to eat everything to enjoy Thai cuisine. Know your limits.
Overly Spicy Foods You’re Not Ready For
Thai food is famous for being spicy, and I mean really spicy. Even dishes that look innocent can pack a serious punch. What locals call “mild” might still set your mouth on fire. If you’re not used to chili heat, some dishes can leave you sweating, crying, or worse… spending the night with stomach cramps.
The first time I tried som tam (papaya salad), I asked the vendor, “Not spicy, please.” She smiled and nodded. But wow, that salad had at least five little red chilis crushed into it. I took one big bite, and my lips started burning. I kept eating to be polite, but I could barely finish it. My tongue was numb, and I had to sit down for a while just to breathe.
Some dishes like tom yum soup, green curry, and pad kra pao can be really spicy without warning. The trick is to say “mai phet” (not spicy) or “phet nit noi” (a little spicy) when you order. Even then, be prepared, it still might be hotter than you expect.
Start slow. Try mild versions first and build up your spice tolerance. Thai food is delicious with or without the heat, so don’t feel bad asking for it your way.
Foods That Are Culturally Inappropriate to Eat
In Thailand, food is more than just something you eat, it’s tied to culture, religion, and respect. Some dishes or ingredients might seem interesting to try, but they can actually be seen as disrespectful or even illegal. One big example is food made from endangered animals like shark fin or turtle. These might be offered at some touristy restaurants, but eating them is frowned upon by locals and is often against the law.
I once walked past a seafood restaurant in a tourist-heavy part of Bangkok and saw “shark fin soup” on the menu. At first, I was curious. But then I remembered reading how cruel and unsustainable that practice is. I skipped it and chose a regular seafood dish instead, and I’m glad I did.
Another tricky one is insects. Fried bugs like crickets, silkworms, or scorpions are sometimes sold as “exotic snacks” to tourists. While some locals do eat them, many vendors sell them just for show. The problem is that they’re not always cooked or stored safely, especially in crowded tourist areas. You could get sick if they’ve been sitting out too long.
One more thing, never touch or eat food meant as an offering to monks or placed at temples. It might look like free fruit or snacks, but those items are sacred. Taking them is highly disrespectful.
It’s always good to try new things, but do a little research first. Being a respectful traveler goes a long way.
Expired or Reused Cooking Oil
Thai street food is often deep-fried, crispy, and full of flavor. But not all oil is fresh. Some food stalls reuse their cooking oil many times, and that can be a problem. Old oil turns dark and sticky, and it can make the food taste bitter or burnt. Worse, it can carry harmful chemicals that build up the more it’s used. You won’t always see the oil, but you’ll taste the difference.
One time in Phuket, I bought a bag of fried chicken bites from a quiet corner vendor. They looked golden and crunchy, but the smell was off. I took one bite and instantly knew something wasn’t right. The chicken was greasy, and the crust tasted like old frying pans. I didn’t even finish it. My stomach was okay, but I felt gross for the rest of the day.
You can avoid bad oil by watching how busy the food stall is. A vendor with lots of customers usually has to cook fresh batches more often, so the oil doesn’t sit around all day. You can also look at the fryer. If the oil looks black or cloudy, skip it.
Crispy food is great, just make sure the crunch is from fresh oil, not leftovers.
Conclusion
Thailand is one of the best places in the world to eat, but knowing what to skip can make your trip way more enjoyable. Stay away from raw seafood, street fruit that’s already cut, and anything made with tap water or crushed ice. Watch out for mystery meats, dishes with raw blood, and extra spicy meals that could surprise your stomach. Respect the culture by avoiding foods made from endangered animals and offerings meant for temples. And always keep an eye on how clean the vendor looks, especially when it comes to fried food and reused oil.
I’ve made a few of these mistakes myself, and I promise, they’re not fun to learn the hard way. But once you know what to avoid, you’ll have no problem finding safe, tasty meals all over Thailand. Trust your gut, literally and figuratively, and don’t be afraid to ask locals or other travelers for tips. Got your own story or food to avoid in Thailand? Drop it in the comments, I’d love to hear what you learned!