Eating raw liver is not safe. It carries real risks of bacterial infection, parasitic disease, viral illness, and vitamin A toxicity, regardless of the animal it comes from. While raw liver has gained popularity in some wellness circles for its nutrient density, the hazards are well-documented and can be severe.
Bacterial Contamination Inside the Liver
Unlike a steak, where bacteria mostly live on the outer surface, liver can harbor pathogens deep inside the tissue. This is the key distinction that makes raw liver particularly dangerous. Campylobacter, one of the most common causes of food poisoning, has been found inside the internal tissue of 10% to 90% of chicken livers even after the outer surface was sanitized. That means washing, searing, or briefly cooking the outside does nothing to eliminate bacteria trapped within.
Salmonella is also commonly present in raw poultry liver. The CDC specifically warns against leaving the center of chicken liver pink or rare, even when making pâté, because Campylobacter survives inside unless the internal temperature reaches 165°F (74°C). You cannot tell whether liver is safe by looking at it or judging its color.
Beef liver carries its own bacterial risks. E. coli and Salmonella can both be present, and because the liver filters blood from the entire digestive system, it’s exposed to a wider range of pathogens than muscle meat.
Parasites That Survive in Raw Liver
Raw cow liver is a significant source of Toxocara infection, a parasitic disease caused by roundworm larvae. Once swallowed, the larvae hatch in the small intestine, penetrate the intestinal wall, enter the bloodstream, and travel to the liver and lungs. There, they form small capsules and can remain alive for extended periods.
A study of patients with unexplained elevations in a type of white blood cell (a hallmark of parasitic infection) found that 87.5% of those who tested positive for Toxocara had recently eaten raw cow liver. Among people who ate raw cow liver four or more times per year, the positive rate climbed to 96.4%. Toxocara infection often shows up as small nodular lesions found incidentally on liver or lung imaging, sometimes with no obvious symptoms until the disease is advanced.
Hepatitis E From Raw Pork Liver
Pork liver introduces an additional risk that beef and poultry do not: hepatitis E virus (HEV). Genotypes 3 and 4 of HEV are zoonotic, meaning they pass from animals to humans. Documented outbreaks in France were traced directly to figatelli, a traditional raw pork liver sausage from Corsica. Researchers found infectious, replicating virus inside the sausage, and genetic sequencing showed a 100% match between the virus in the leftover sausage and the virus in the patient who fell ill.
Hepatitis E typically causes acute liver inflammation with symptoms like fatigue, nausea, jaundice, and abdominal pain. In most healthy adults it resolves on its own, but it can become chronic and life-threatening in people with weakened immune systems.
Vitamin A Toxicity
Liver is the most concentrated dietary source of preformed vitamin A. A single 100-gram serving of beef liver contains roughly 5,000 to 9,000 micrograms of retinol, depending on the animal’s age and diet. The tolerable upper intake level for adults is 3,000 micrograms per day. That means one modest serving of liver can deliver two to three times the safe daily limit in a single sitting.
Occasional consumption of cooked liver is unlikely to cause problems for most adults, but eating it frequently, or in large amounts, can lead to hypervitaminosis A. Acute symptoms include nausea, headache, dizziness, and blurred vision. Chronic overconsumption causes more serious effects: liver damage, bone thinning, and skin changes. This risk exists whether the liver is raw or cooked, since vitamin A is heat-stable, but people who eat raw liver as a daily “superfood” habit are especially vulnerable to accumulating toxic levels.
Pregnancy Is an Especially High-Risk Scenario
The NHS advises pregnant women to avoid liver and liver products entirely, whether raw or cooked. Excessive vitamin A during pregnancy can cause birth defects and developmental harm to the fetus. Beyond that, raw and undercooked meat carries a risk of toxoplasmosis, which can cause miscarriage. For pregnant women, there is no amount of raw liver that is considered safe.
Does Freezing Make Raw Liver Safe?
Freezing can kill certain parasites, but the conditions required are stricter than a typical home freezer reliably achieves. The FDA recommends that foods intended for raw consumption be frozen to minus 35°C (minus 31°F) for at least 15 hours, or to minus 20°C (minus 4°F) for 7 days. Research on parasitic larvae shows that even at minus 20°C for 24 hours, some larvae in whole tissue samples survived and showed spontaneous movement after thawing. Complete kill required either 48 hours at minus 20°C or a more powerful commercial blast freezer.
More importantly, freezing does not reliably eliminate bacteria. One study found that Campylobacter was less common in frozen-then-thawed chicken liver compared to fresh (16% versus 31%), but that still leaves a meaningful contamination rate. Freezing also does not destroy hepatitis E virus or reduce vitamin A content. So while proper freezing may lower parasitic risk, it does not make raw liver safe to eat overall.
What the Evidence Adds Up To
The risks of eating raw liver are not theoretical. Internal bacterial contamination rates in chicken liver reach as high as 90%. Nearly all frequent raw cow liver consumers in one study tested positive for a parasitic infection. Hepatitis E has been directly traced to raw pork liver sausage with genetic precision. And the vitamin A content alone can exceed safe limits in a single serving. Cooking liver to the recommended internal temperature eliminates the bacterial and parasitic risks, and remains the only reliable way to make it safer to eat.