Liver is one of the most nutrient-dense foods available, packed with protein, B vitamins, vitamin A, iron, copper, and choline in concentrations that far exceed most other whole foods. A 100-gram serving of raw beef liver contains about 20 grams of protein, just 3.2 grams of fat, and 3.5 grams of carbohydrate, making it a lean, high-protein food with a remarkably broad nutrient profile.
Vitamin A
Liver is the single richest dietary source of preformed vitamin A (retinol). A three-ounce serving of pan-fried beef liver delivers well over the daily recommended amount for most adults. This is the active, ready-to-use form of the vitamin, unlike the beta-carotene found in carrots and sweet potatoes that your body has to convert first. Vitamin A supports vision, immune function, and cell growth.
That potency comes with a caveat. The tolerable upper intake level for preformed vitamin A in adults is 3,000 mcg per day, and a single serving of beef liver can exceed that threshold. Eating liver once or twice a week is generally enough to reap the benefits without pushing into excess. Pregnant women need to be especially cautious, since very high vitamin A intake is linked to birth defects.
B Vitamins
Liver is loaded with nearly every B vitamin, but it particularly stands out for vitamin B12, riboflavin (B2), niacin (B3), and folate. A single serving of beef liver provides many times the daily recommended intake of B12, a vitamin essential for nerve function and red blood cell production. Folate, critical for DNA synthesis and especially important during pregnancy, is also present in significant amounts.
Riboflavin helps your body convert food into energy and supports healthy skin and eyes. Niacin plays a role in metabolism and DNA repair. Together, these B vitamins make liver one of the few foods that can meaningfully address multiple B vitamin needs at once.
Choline
Three ounces of beef liver contains roughly 356 milligrams of choline, making it the top whole-food source of this nutrient. For comparison, a large hard-boiled egg delivers about 147 milligrams. Chicken liver is also rich, with about 246 milligrams per three-ounce serving.
Choline is essential for brain health, liver function, and muscle movement. It’s a building block of cell membranes and a precursor to a neurotransmitter involved in memory and mood. Most people don’t get enough choline from their diet, so liver is one of the most efficient ways to close that gap.
Iron and Its Bioavailability
Liver provides heme iron, the form found in animal foods that your body absorbs far more efficiently than the nonheme iron in plant foods like spinach or lentils. Heme iron makes up only 10% to 15% of total iron intake in people who eat meat, yet it contributes up to 40% of the iron actually absorbed. That efficiency is what makes liver especially valuable for people with low iron stores or those at risk of iron-deficiency anemia.
Cooked chicken liver provides about 3.6 milligrams of iron per ounce. Beef liver is similarly rich. A three-ounce serving can supply a substantial portion of the daily iron requirement, which ranges from 8 milligrams for adult men to 18 milligrams for premenopausal women.
Copper
Copper often gets overlooked, but liver is an extraordinarily concentrated source. Three ounces of pan-fried beef liver contains about 12.4 milligrams of copper, which actually exceeds the tolerable upper intake level for adults of 10 milligrams per day. That sounds alarming, but your body has built-in safeguards: copper absorption in the intestine and copper release through bile work together to maintain balance.
Copper supports iron metabolism, connective tissue formation, and immune health. Occasional servings of liver won’t cause problems for most healthy adults, but eating it daily could lead to excess copper accumulation over time, potentially causing liver damage, abdominal cramps, nausea, or diarrhea. Spacing servings across the week is the practical approach.
Other Minerals
Beyond iron and copper, liver contains meaningful amounts of zinc, selenium, and phosphorus. Zinc supports immune function and wound healing. Selenium acts as an antioxidant and is important for thyroid health. Phosphorus contributes to bone structure and energy production. These minerals appear alongside the vitamins and iron, which is part of what makes liver so unusually nutrient-dense per calorie.
How Cooking Affects the Nutrients
Cooking liver does reduce some of its vitamin content, particularly the water-soluble B vitamins. USDA data on simmered turkey livers shows that boiling retains only about 47% of riboflavin, 58% of thiamine, and 43% of niacin. Retinol (vitamin A) fares slightly better, with about 51% retained after simmering. These losses are typical for water-soluble vitamins in any food cooked in liquid.
Quick, dry-heat methods like pan-searing tend to preserve more nutrients than prolonged boiling, because less vitamin content leaches into cooking water. Even with those losses, cooked liver remains far more nutrient-dense than most other foods. The starting concentrations of B vitamins and vitamin A are so high that even half the original amount is still substantial.
Who Should Be Cautious
Liver’s density of vitamin A and copper means it’s possible to overconsume both nutrients if you eat it frequently. Keeping intake to one or two servings per week avoids most concerns for healthy adults. People with gout or elevated uric acid levels should know that liver is a high-purine food, containing up to 220 milligrams of purines per 100 grams of raw beef liver, which places it well above regular cuts of beef (77 to 123 milligrams per 100 grams). High-purine foods can trigger flare-ups in people prone to gout.
People with Wilson’s disease or other copper metabolism disorders need to avoid liver entirely, since even a single serving delivers a very large copper dose. Pregnant women should limit intake because of the vitamin A content, as preformed vitamin A in excess is associated with teratogenic effects.