Eating organ meat may not be as popular in modern cuisine as it traditionally was, but liver is a nutrient-dense superfood. Although there are some pros and cons of eating liver, it can be a healthy addition to your diet.
As well as familiar beef and chicken liver, other types such as mutton, duck and goat liver contain high-quality protein and are a potent source of vitamins A and B, especially B12, and minerals including phosphorus, iron, copper and selenium.
Ounce for ounce, liver may be one of the most nutritious foods you can eat, as long as you are aware of the risks of consuming too much.
Beef and Mutton Liver Nutrition
Beef, chicken and mutton liver nutrition differs only slightly in calorie, carbohydrate and total fat content. For example, per 100-gram portion, which is just under 4 ounces, beef liver nutrition includes:
- 135 calories
- 3.9 grams of carbohydrates
- 3.6 grams total fat
- Liver does not contain any fiber or sugar
If you fry your liver in oil or butter, and garnish it with bacon, you can easily double the calories and fat content.
Good Source of Protein
Considered a complete protein, liver contains all the essential amino acids that your body cannot make on its own. Amino acids are the building blocks for protein needed for many functions including the maintenance of muscle mass, tissue repair, growth and development, hormone production and keeping your skin and hair healthy.
Each of the amino acids in liver has a role in keeping you healthy. For example, 100 grams of beef liver contains 1.25 grams of arginine, which may help to reduce blood pressure in hypertensive adults, according to a study published in Journal of Chiropractic Medicine in September 2016. Threonine in beef liver — 0.87 grams per 100 grams — is important for tooth enamel, collagen and elastin. Valine in liver promotes muscle growth and repair with 1.27 grams per 4 ounces.
Fats and Fatty Acids in Liver
Although liver contains healthy mono- and polyunsaturated fatty acids, it also contains unhealthy trans fats and saturated fat. The Dietary Guidelines recommends limiting saturated fat to less than 10 percent of your daily caloric intake. Saturated and trans fats are associated with cardiovascular disease, so you should avoid eating too much liver if you have a heart condition. Mutton liver contains more saturated fat than beef or chicken liver.
While the Dietary Guidelines has not set an upper limit for dietary cholesterol, the recommendation is to restrict your intake as much as possible. American Heart Association advises that high cholesterol contributes to an increased risk for cardiovascular problems, such as heart disease and stroke. Since your body is able to make its own cholesterol, the foods you eat, such as liver, can impact your cholesterol levels.
Antioxidants for Immune System
All these nutrients help to reduce inflammation by fighting damaging free radicals. Free radicals are molecules formed as a byproduct of metabolic functions, such as digestion, and also from environmental factors, such as pollution. According to University of Michigan Michigan Medicine, free radicals may play a role in more than 60 different health conditions including cancer, the aging process and arteriosclerosis.
Nature’s B Complex for Stress
Liver contains all of the B vitamins in significant amounts, including vitamin B12, thiamine, niacin, B6, riboflavin, pantothenic acid and folate. The group of B vitamins are necessary for providing your body with energy to carry out metabolic functions involving your muscles, nervous system, skin, heart and brain.
Per 100 grams, chicken, beef and mutton liver benefits functions, including your nervous system, by providing well over 100 percent of your DV for vitamin B12 and riboflavin. Chicken livers also provide more than your daily recommended intake for folate, which is important during pregnancy for the prevention of birth defects.
Vitamin B may help reduce stress and fatigue as well as improve mood. In an Australian study, a group of full-time employees given antioxidants and B vitamins had an improvement in cognitive ability and mood. The evidence, published in the Nutrition Journal in July 2014, suggested that dietary supplementation of B vitamins may be viable in reducing occupational stress, increasing work productivity and decreasing absenteeism.
Improves Bone Density
Eating liver may help protect your bone density with the many nutrients it contains that contribute to keeping your whole skeletal system strong. Liver is a good source of magnesium, calcium, phosphorus, potassium, iron, zinc and copper, which help to build the structural platform for bone formation and growth, according to American Bone Health.
Magnesium help reduce the risk of osteoporosis in women after menopause, according to National Institutes of Health.
Calcium is primarily stored in bones and teeth, where it's needed to maintain structure and hardness.
Phosphorus is important for strong bones, considering 85 percent of your body's phosphorus is found in your bones in the form of calcium phosphate.
Potassium helps neutralize metabolic acids to conserve calcium and reduce urinary loss of the mineral.
Iron, zinc and copper are needed for collagen
to help hold bones together.
Good Source of Vitamin A
Liver is among the best sources for vitamin A, with beef liver containing 16,899 IU or 338 percent DV. Vitamin A is important for your immune system and good vision. It also helps your lungs, kidney and heart to work properly. Vitamin A found in liver is the preformed or active form, also called retinol. This form can be used directly by your body and does not need to be converted first like vitamin A in plant-based foods.
A deficiency in vitamin A is rare but could occur as a result of an increased demand, such as during infancy, childhood, pregnancy or lactation. Vitamin A has been shown to be especially useful for children with certain diseases or conditions in developing countries.
The World Health Organization reported that severe measles is more likely among young children deficient in vitamin A, and supplementation of the vitamin may prevent eye damage and reduce the number of deaths from measles. Furthermore, results of a Spanish study published in Revista De Salud Publica in May-June 2014 concluded that an intake of vitamin A was a cost-effective approach to reducing diarrhea, malaria and mortality in young Colombian children.
Health Risk of Vitamin A
Because vitamin A is fat soluble, your body stores excess amounts that can accumulate in your body. You should not consume more than the recommended tolerable upper intake level (UL) of 3,000 micrograms daily. Excessive vitamin A can lead to toxicity, known as hypervitaminosis A. Following excessive intake over time or a massive single dose of vitamin A, symptoms of hypervitaminosis A can lead to increased pressure on the brain, dizziness, nausea, headaches, irritation of the skin, joint and bone pain, coma and even death.
The National Institutes of Health suggests that more than 1,500 micrograms per day might reduce bone mineral density and raise your risk for fractures. Taking more that the UL of preformed vitamin A can cause congenital birth defects, including malformations of the eyes, skull, lungs and heart. NIH recommends that women who might be pregnant should limit the amount of liver they consume.
- Berkeley Wellness: "How Nutritious Is Liver?"
- USDA Food Composition Database: "Beef, Variety Meats and By-Products, Liver, Raw"
- USDA Food Composition Database: "Lamb, Variety Meats and By-Products, Liver, Raw"
- USDA Food Composition Database: "Chicken, Liver, All Classes, Raw"
- The New York Academy of Sciences: Annals: "The Importance of Dietary Protein for Muscle Health in Inactive, Hospitalized Older Adults"
- Journal of Chiropractic Medicine: "Therapeutic Benefits of l-Arginine: An Umbrella Review of Meta-Analyses"
- NIH PubChem: "L-Threonine"
- NIH PubMed: "Valine"
- Dietary Guidelines: "Limit Calories from Added Sugars & Saturated Fats & Reduce Sodium Intake"
- USDA Choose My Plate: "Dietary Guidelines: Do I Still Need to Watch My Cholesterol Intake?"
- American Heart Association: "Understanding & Managing Cholesterol"
- Michigan Medicine: "Antioxidants and Free Radicals"
- Nutrition Journal: "Reducing Occupational Stress With a B-Vitamin Focussed Intervention: A Randomized Clinical Trial: Study Protocol"
- American Bone Health: "Minerals for Bone Health"
- National Institutes of Health: "Magnesium"
- National Institutes of Health: "Calcium Fact Sheet for Consumers"
- National Institutes of Health: "Potassium"
- National Institutes of Health: "Vitamin A"
- World Health Organization: "Measles"
- Revista De Salud Publica: "Cost-Effectiveness Analysis (CEA) Regarding Vitamin A in Children Aged Less Than 5 Years-Old in Colombia"
- National Academies Press: "Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc"
- National Institutes of Health: "Selenium"