Preventing parasites in food comes down to four things: cooking meat to the right temperature, washing produce thoroughly, freezing fish before eating it raw, and avoiding cross-contamination in the kitchen. The most common foodborne parasites in the United States include Toxoplasma, Cryptosporidium, Giardia, Cyclospora, Trichinella (in meat), Anisakis (in fish), and tapeworms. Each one has a different route into your body, so the prevention strategies depend on what you’re eating.
Wash Produce Under Running Water
Parasites like Cyclospora and Toxoplasma can cling to the surface of fresh fruits and vegetables, picked up from contaminated soil or irrigation water. Washing is your first and most practical line of defense, though it’s worth understanding what washing can and can’t do.
The CDC recommends washing all fruits and vegetables thoroughly under running water before eating, cutting, or cooking them. For firm produce like melons and cucumbers, use a clean produce brush to scrub the surface. Cut away any damaged or bruised areas before preparing. Produce labeled “prewashed” does not need to be washed again.
Here’s the honest reality: washing reduces parasite contamination but doesn’t eliminate it completely. A study testing multiple wash solutions on basil contaminated with Cyclospora, Cryptosporidium, and Toxoplasma found that parasites were still detectable across every wash method tested, including specialized lab solutions far stronger than anything you’d use at home. Plain water, vinegar rinses, and commercial produce washes all help remove surface contamination, but none of them guarantee a parasite-free result. This is why cooking remains the most reliable kill step for produce you’re concerned about, especially leafy greens and herbs that can’t be peeled.
Cook Meat to Safe Temperatures
Cooking is the single most effective way to kill parasites in meat. Toxoplasma in pork and lamb, Trichinella in wild game, and tapeworm larvae in beef are all destroyed by sufficient heat. The key number to remember for most meats is an internal temperature of 160°F (71°C), held for at least three minutes.
Use a meat thermometer every time. Color alone is unreliable. A burger can look brown throughout and still not have reached a temperature high enough to kill parasites, while a properly cooked piece of pork might retain a slight pink tint.
Wild Game Requires Extra Caution
Bear, wild boar, and other wild game carry a particularly high risk for Trichinella. Alaska’s Department of Fish and Game advises hunters to assume all bear meat is infected, since the larvae are microscopic and invisible to the naked eye. The species of Trichinella found in wild game from northern regions, called T. nativa, is adapted to arctic conditions and cannot be killed by freezing. In one study, infected polar bear meat frozen at minus 18°C for six years still contained viable parasites. Fox meat frozen for four years also harbored living larvae.
This means that for wild game, especially bear, curing, salting, drying, smoking, and microwaving are all unreliable. Homemade jerky and sausage have been responsible for many recent trichinellosis cases reported to the CDC. The only safe method is thorough cooking to 160°F throughout, with a three-minute rest at that temperature.
Freeze Fish Before Eating It Raw
If you eat sushi, sashimi, ceviche, or any other raw fish preparation, freezing is the standard safety measure for killing Anisakis and other fish parasites. The FDA’s guidelines for commercially prepared raw fish require one of the following:
- Standard freeze: Store at -4°F (-20°C) or below for 7 days total.
- Blast freeze: Freeze at -31°F (-35°C) or below until solid, then store at -31°F (-35°C) for 15 hours.
- Blast then hold: Freeze at -31°F (-35°C) or below until solid, then store at -4°F (-20°C) or below for 24 hours.
Most home freezers hover around 0°F (-18°C), which is not cold enough to meet the FDA’s standard. Reputable sushi restaurants and fish suppliers use commercial freezers that reach the required temperatures. If you’re buying fish to eat raw at home, ask your fishmonger whether it has been previously frozen to FDA parasite-destruction specifications. Fish thicker than six inches may not freeze uniformly enough for these guidelines to be effective.
Choose Pasteurized Beverages
Unpasteurized apple cider, fruit juices, and raw milk can carry Cryptosporidium and Giardia, two parasites that cause prolonged diarrheal illness. The fruit used in fresh-pressed juices can pick up contamination from the farm environment, during handling, or in processing. Freezing or refrigerating unpasteurized drinks does not kill these parasites. Pasteurization is the only process that reliably eliminates them.
If you’re buying juice or cider at a farmers’ market, roadside stand, or orchard, ask the seller whether the product has been pasteurized. People with weakened immune systems, young children, and older adults face the highest risk and should stick to pasteurized products exclusively. Check the label on any bottled juice, since pasteurized and unpasteurized versions often sit on the same shelf.
Prevent Cross-Contamination in the Kitchen
Even if you plan to cook your meat thoroughly, parasite cysts and larvae can transfer to foods you won’t be cooking, like salads and bread, through shared surfaces and utensils. The fix is straightforward: use one cutting board for raw meat, poultry, and seafood and a separate one for produce, bread, and anything that won’t be cooked. Wash cutting boards, utensils, and countertops with hot, soapy water after preparing each food item.
Wash your hands with soap and water before and after handling raw meat or unwashed produce. This is especially important when you’re switching between tasks, like moving from trimming raw chicken to chopping vegetables for a side dish. A quick rinse under water isn’t enough. Soap breaks down the outer walls of certain parasite cysts in a way that water alone does not.
Travel and High-Risk Situations
Many foodborne parasite infections in the U.S. are actually acquired abroad. Cyclospora outbreaks, for instance, are frequently linked to imported produce from regions where the parasite is common in soil and water. When traveling to areas with less reliable water treatment, avoid raw salads, unpeeled fruits, and ice made from tap water. Stick to cooked foods served hot, fruits you can peel yourself, and bottled or boiled water.
At home, the biggest risk factors are raw or undercooked meat (especially wild game and pork), raw fish that hasn’t been properly frozen, unwashed produce, and unpasteurized beverages. You don’t need to avoid any of these foods entirely. You just need to apply the right kill step for each one: heat for meat, commercial freezing for raw fish, thorough washing for produce, and pasteurization for juices and cider.