Beef Liver Supplements: 5 Things to Know Before You Buy

Organ supplements are one of the fastest-growing trends in natural health. Liver has earned its reputation as a superfood. Here is what a capsule can and can’t do, and why the real thing still wins.

In the early 1920s, a diagnosis of pernicious anemia was a death sentence. Patients grew pale and weak, their nerves began to fail, and within a few years most were gone. Boston physician George Minot knew something about death sentences. In the early 1920s he had been diagnosed with diabetes, and he survived only because insulin became available just in time, in 1923.

Minot suspected diet might matter in anemia. So he and his colleague William Murphy tried something radical: they fed their patients about half a pound of liver every single day. In 1926 they reported the results in the Journal of the American Medical Association. Their 45 patients, who should have been dying, were recovering. In 1934, Minot, Murphy, and George Whipple, whose experiments on dogs had pointed to liver first, shared the Nobel Prize.

There was just one problem. Patients hated eating that much liver. So drug companies started concentrating it into extracts, the first “liver supplements,” nearly a century before anyone posted one on social media. It took until 1948 for scientists to isolate the compound in liver that saved those lives: vitamin B12.

Today liver is having a second moment. Over the past year, searches for “organ supplement” have climbed nearly 300%, and searches for “beef liver supplement” are up 94%, fueled by nose-to-tail eating, carnivore diets, and ancestral health influencers. If you read this issue’s lead article on low iron, you may be wondering whether a bottle of liver capsules is the answer. The truth is more interesting than the hype.

What’s actually in liver

Gram for gram, liver is one of the most nutrient-dense foods you can eat. It is the body’s storage warehouse, which is exactly why it is packed with what it stores. A 3-ounce serving of cooked beef liver provides roughly:

• Vitamin B12: about 70 mcg, nearly 30 times the daily value
• Vitamin A: about 6,600 mcg, more than 7 times the daily value
• Copper: about 12 mg, more than 13 times the daily value
• Iron: about 5 mg, roughly 28% of the daily value
• Plus generous amounts of choline, riboflavin, folate, and zinc

Look closely at that list, and you’ll notice something. Liver’s true superpowers are B12, vitamin A, and copper. Its iron is good, but not spectacular. A 3-ounce serving of oysters has more. And chicken liver offers nearly twice the iron of beef liver with roughly half the vitamin A, which makes it the better pick if iron is your main goal.

The capsule math

Here is what most supplement labels won’t spell out. Fresh liver is about 70% water. Desiccated liver supplements are dried, so a typical daily serving of six 500 mg capsules, 3,000 mg in all, equals only about a third of an ounce of fresh liver. That is two or three bites.

Run the numbers on that serving, and you get well under 1 mg of iron. For someone who is truly iron deficient and needs to rebuild ferritin, that is a drop in the bucket. Liver capsules are not a treatment for iron deficiency, and they are not a substitute for testing and targeted treatment.

Where capsules do deliver is vitamin B12. The same serving supplies several times the daily value, plus a meaningful dose of vitamin A. That’s useful, but it also brings us to the part of the liver story that gets left out.

READ THE LABEL

Amounts vary widely by brand. Look for the milligrams of liver per serving, not just per capsule, and check whether the label lists actual vitamin A, B12, and iron content.

Choose products with third-party testing from a group like NSF or USP, and look for the country of origin. Freeze-dried products are generally processed more gently than heat-dried ones.

Remember that supplements are not approved by the FDA before they are sold. Quality is up to the manufacturer.

When liver becomes too much of a good thing

In December 1912, the Australian explorer Douglas Mawson and his companion Xavier Mertz were stranded in Antarctica, hundreds of miles from base, after their teammate and most of their food disappeared into a crevasse. To survive, they ate their sled dogs, including the livers. Within weeks, Mertz was dead. Mawson barely made it back, with his hair falling out, his skin peeling, and the soles of his feet coming off in layers. Many researchers have since blamed vitamin A poisoning from the dog livers, which are extraordinarily rich in it. Historians still debate it, since starvation alone can cause some of the same symptoms, but the episode became a classic warning about eating too much liver.

No one is eating husky liver today, but the lesson holds. Vitamin A from animal sources is stored in the body, not flushed out. The safe upper limit for adults is 3,000 mcg per day, and a single 3-ounce serving of beef liver contains more than twice that. Eaten once a week, that is fine; your body draws down its stores between servings. Eaten every day, or stacked with a multivitamin, cod liver oil, and liver capsules, it can add up.

Too much vitamin A over time is linked to liver damage, headaches, and weaker bones. In the Nurses’ Health Study, which followed more than 72,000 postmenopausal women, those who got 2,000 mcg or more of preformed vitamin A a day had nearly twice the risk of hip fracture of women getting less than 500 mcg, a finding published in JAMA in 2002. Copper works the same way: the upper limit is 10 mg a day, and a serving of beef liver tops it.

What about heart, kidney, and “glandulars”?

Many organ supplements go beyond liver, blending heart, kidney, spleen, pancreas, and glands like the thyroid and adrenals. The pitch rests on an old idea called “like supports like”: eat heart to support your heart, adrenal to support your adrenals. It’s a compelling story, but there is very little human research to back it up.

Organ meats do contain real nutrients. Heart, for example, is one of the richest food sources of CoQ10. But some glandular products carry a hidden risk. In a 2013 study in the journal Thyroid, researchers tested 10 over-the-counter “thyroid support” supplements. Nine contained measurable amounts of the thyroid hormone T3, and five contained T4, the active ingredient in prescription thyroid medication. One product’s daily dose held more than 90 mcg of T4. A typical prescription starting dose is 25 mcg. If you read last month’s issue on Hashimoto’s, you’ll see the problem: people could be taking thyroid hormone without knowing it, on top of their prescription or without any testing at all.

How to eat the real thing (and actually like it)

For most people, the best way to get liver’s benefits is the way Minot’s patients did: as food, in moderate amounts. About 3 to 4 ounces once a week gives you a generous dose of B12, copper, vitamin A, and iron without overdoing it. If the taste puts you off, try these tricks:

• Soak it first. Soaking sliced liver in milk or lemon water for an hour mellows the strong flavor.
• Start with chicken livers. They are milder and more tender than beef. Sautéed with onions or blended into a pâté, they win over many skeptics.
• Hide it. Finely grind or grate a small amount of frozen liver into ground beef for burgers, meatballs, or chili. About a quarter pound of liver per pound of beef is barely noticeable.
• Don’t overcook it. Liver turns tough and bitter when cooked through. Sear it quickly so it stays slightly pink inside.
• Pair it wisely. Serve it with vitamin C-rich vegetables like peppers or tomatoes, and save the coffee or tea for later, to get the most from its iron.

WHO SHOULD SKIP LIVER AND ORGAN SUPPLEMENTS

• Pregnant women or those trying to conceive: high preformed vitamin A can harm a developing baby. Talk with your doctor about safe amounts.
• People with gout: organ meats are very high in purines, which can trigger flares.
• People with hemochromatosis or Wilson’s disease, conditions in which the body builds up too much iron or copper.
• Anyone already taking vitamin A, cod liver oil, or a high-dose multivitamin, or prescription retinoids like isotretinoin.
• Anyone taking thyroid medication, before trying a glandular blend.

The bottom line

George Minot didn’t prescribe liver because it was trendy. He prescribed it because it saved lives, at half a pound a day, under a doctor’s watch, for a specific deficiency. Nearly a century later, liver still deserves its place as one of nature’s most powerful foods.

But a few capsules of dried liver are not Minot’s cure in a bottle. If you’re tired and suspect low iron, start with the ferritin test from this issue’s lead article. If you want liver’s benefits, put it on your plate once a week. Treat it as food, not magic, and it will treat you well.

These statements have not been evaluated by the Food and Drug Administration. This article is for educational purposes only and is not intended to diagnose, treat, cure, or prevent any disease. Talk with your healthcare provider before starting any supplement.