Today’s guest post is written by Terry Wahls, M.D., Institute for Functional Medicine Certified Practitioner, clinical professor of medicine at the University of Iowa and author of The Wahls Protocol: How I Beat Progressive MS Using Paleo Principles and Functional Medicine (paperback). You may be familiar with her recovery story, featured here .
I heard a lot of you want to know more about liver! I’m glad you are curious. Liver is great for you, and you need only eat 6 to 8 ounces per week to gain its benefits. I limit liver because it is quite high in retinol, which is the active form of vitamin A. Retinol is involved in the management of cell differentiation and immune function. Carotenoids in colorful fruits and vegetables can be converted to retinol; however, the efficiency of these enzymes depends on the efficiency of Beta-carotene 15’-15’ oxygenase, which varies  based on one’s underlying genetics. Some single nucleotide polymorphisms have a 70% reduction in the efficiency of this conversion.
Inadequate levels of vitamin A are associated with higher rates of dysplasia, infection, and autoimmunity. It is likely that patients with chronic infections, autoimmunity, dysplasia, or cancers have a higher requirement for vitamin A intake than someone who is healthy. But scientists have not determined the optimal intake for those with infection, autoimmunity, dysplasia, or cancer.
Complicating what amount of retinol to recommend is that the therapeutic range for retinol intake is relatively narrow, and excessive retinol intake also has health risks. Acute retinol intoxication is very rare (Arctic explorers died of retinol intoxication caused by eating polar bear liver). Chronic retinol intoxication is associated with serious birth defects, which is why Accutane®, an analog of retinol that is used to treat severe acne, has a black box warning advising women to have a pregnancy test before starting Accutane® and to use reliable birth control if taking Accutane®. In addition to birth defects, chronic excesses of retinol can lead to irreversible fibrosis and scarring of the liver and lungs. If you have developed fibrosis of the liver or lungs as a result of retinol intoxication, the damage is irreversible. Because vitamin A is a fat-soluble vitamin, excess vitamin A accumulates in the fat. It takes a long time for vitamin A levels to decline.
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The tolerable upper limit for retinol  is defined as the maximum daily intake that is unlikely to be associated with the development of disease. However, an individual with high consumption of alcohol, high cholesterol, or chronic liver or lung disease may have a lower tolerable upper limit. For men older than 19 and women older than 51, the tolerable upper limit is 3,000 ?g/day of retinol. The limit for pregnant women is 2,800 ?g/day.
For all these reasons, I recommend limiting liver to 6 to 8 ounces per week. For those who consume liver regularly, I recommend taking fish oil instead of cod liver oil, which also contains retinol. The following list indicates the amount of retinol in 3 ounces of braised (simmered) liver from a variety of animals.
- Beef 7,350
- Lamb 6,379
- Pork 5,405
- Chicken 3,360
- Turkey 3,360
Liver can have a strong taste. If it is overcooked, it becomes dry, leathery, and quite unpleasant. It is best cooked medium-rare. My family enjoys a Middle Eastern recipe for Lamb Liver and Parsley Onion Salad (recipe below). Other options to make liver more palatable is to pulse it in a food processor and blend it with ground meat at a ratio of 90% ground meat and 10% liver. You can use this ground meat as you would normally.
Middle Eastern Lamb Liver and Parsley Onion Salad
Excerpted from The Wahls Protocol: A Radical New Way To Treat All Chronic Autoimmune Conditions Using Paleo Principles
- 1 lb lamb liver, sliced
- ½ to 1 tsp ground cumin
- 1 tablespoon apple cider vinegar
- 1 tablespoon ghee (or extra virgin olive oil)
- Sea salt and black pepper to taste
- 1 red onion
- 1 bunch of parsley
- 1-2 tablespoons of powdered sumac (if not available may replace with pomegranate seeds)
- 3 tablespoons extra virgin olive oil
- 1 tablespoon balsamic vinegar
Prepare the salad. Quarter red onion and slice thinly. Chop parsley leaves. Mince the stems. Add the powdered sumac, extra virgin olive oil, and balsamic vinegar and stir.
Prepare the liver. Melt ghee in the skillet. Add vinegar and heat on medium until steaming. Add cumin and stir. Add liver and cover. Cook 1 to 2 minutes, then flip and cook 1 minute to 2 minutes more. Remove from heat. Allow to sit for 5 minutes. The goal is to rare or medium-rare liver. If the liver is well done, it will be tough and taste like cardboard.
Serve liver with the parsley onion salad. If you have leftover liver, you can make Liver Paté to have later in the week.
Liver Paté Recipe
- Leftover liver (cooked)
- 3-4 cloves of garlic (chopped)
Chop leftover liver and place in a food processor with olive oil and garlic. Pulse until blended into a smooth mixture. I serve liver paté with guacamole, raw vegetables, or rolled up in a kale leaf with hot sauce or ginger sauce.
My teenage children and their friends agree that liver can be delicious. The key is to not overcook it!
Liver is a superfood and an excellent source of fat-soluble vitamins such as retinol (premade vitamin A), vitamin D, vitamin K, vitamin B12, B9 (folate), B1 (thiamine), and key minerals, including zinc and copper. I urge people with any immune issues to have liver once per week for its excellent nutrient profile.
If using a supplement for your organ meat, there are several factors to consider. I do not recommend brain due the potential for prion-mediated disease being transmitted via brain tissues. I do recommend organic, grass-fed, and grass-finished organ meat. A mix of organs, including liver, heart, and kidney (but not brain), is ideal. Review the label and do not exceed 6 to 8 ounces of liver per week.
All nutrients, even water, have a u-shaped curve that determines the optimal intake for that nutrient. Too little and you develop signs and symptoms of disease. Too much, and once again, you develop signs and symptoms of disease. If we are too short on water, we become dehydrated, can have kidney damage and delirium, and can even die of dehydration. If we have too much water, we become water intoxicated, our blood sodium level falls, and we can experience delirium, severe brain damage, and even death. It is always going to be safer to consume food than take supplements. That is why I recommend eating a wide variety of organ meats – liver, heart, mussels, oysters, tongue, bone marrow, and bone broth. You will find my recipes for organ meats in my cookbook, The Wahls Protocol Cooking for Life The Revolutionary Modern Paleo Plan To Treat All Chronic Autoimmune Conditions https://terrywahls.com/wahls-protocol-cooking-for-life/ and my new and expanded (with 30% new material) The Wahls Protocol A Radical New Way to Treat Chronic Autoimmune Conditions. https://terrywahls.com/the-wahls-protocol/
About Terry Wahls, M.D.
Terry L. Wahls, M.D., is a clinical professor of medicine at the University of Iowa Carver College of Medicine in Iowa City and the director of the Therapeutic Lifestyle Clinic at the Iowa City Veterans Affairs Health Care System, where she treats veterans with autoimmune, neurological, and medical problems using diet and lifestyle interventions. In addition, she is a clinical researcher, studying the use of diet and lifestyle interventions in autoimmune and other chronic disease states; her current clinical trial featuring the Wahls Paleo Diet received the support of the National Mutliple Sclerosis Society. Diagnosed in 2000 with multiple sclerosis, Dr. Wahls became a proponent of integrative and functional medicine, which helped her create an intensive nutrition, lifestyle, and neuromuscular electrical stimulation protocol that would treat the severe disability caused by her MS. She has made it her mission to spread the word about The Wahls Protocol and her own inspirational story of recovery through her TEDx talk, which has received more than 3 million hits; her website, www.terrywahls.com ; the Wahls Foundation; and Wahls Protocol Seminars.
- Carlo dela Seña, Kenneth M. Riedl, Sureshbabu Narayanasamy, Robert W. Curley, Jr., Steven J. Schwartz,and Earl H. Harrison. The Human Enzyme That Converts Dietary Provitamin A Carotenoids to Vitamin A Is a Dioxygenase. J Biol Chem. 2014 May 9; 289(19): 13661–13666.
- Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. National Academy of Sciences 2001
- Terry Wahls MD, Author: The Wahls Protocol Cooking for Life: The Revolutionary Modern Paleo Plan to Treat All Chronic Autoimmune Conditions and The Wahls Protocol A Radical New Way To Treat All Chronic Autoimmune Conditions