Macronutrients: Protein and Energy
Per 100g, liver is an excellent source of high-quality protein, crucial for muscle repair, hormone production, and overall cellular function. The protein content varies slightly by animal source. For example, a 100g portion of cooked beef liver contains approximately 29g of protein, while cooked chicken liver provides around 26g. In contrast to muscle meats, liver generally contains a moderate amount of fat, with most of its calories coming from protein. A 100g serving of beef liver has about 5.3g of fat, and chicken liver has a slightly higher 6.5g. Carbohydrates are minimal, with most liver types containing only a few grams per 100g, making it a low-carb, nutrient-dense food choice.
Vitamins: The Concentrated Powerhouse
Liver's reputation as a superfood stems from its incredibly high vitamin content. No other single food item provides such a concentrated array of fat-soluble and water-soluble vitamins.
Vitamin A
Per 100g, beef liver delivers an astonishing amount of Vitamin A, often exceeding 500% of the Daily Value (DV). This is a preformed, active version of the vitamin (retinol), which is immediately available for the body's use. Vitamin A is vital for:
- Maintaining healthy vision and preventing age-related macular degeneration.
- Supporting the immune system and fighting off infections.
- Ensuring proper cell growth and reproduction.
B-Vitamins
The liver is particularly renowned for its B-vitamin profile. For example, a 100g serving of beef liver can provide thousands of percent of the DV for Vitamin B12, a nutrient critical for nerve function, red blood cell formation, and DNA synthesis. Riboflavin (B2) and Folate (B9) are also present in significant quantities, both essential for energy metabolism and cell growth.
Other Vitamins
While less concentrated than Vitamins A and B12, liver also offers a good amount of Vitamin B6, pantothenic acid (B5), and a small but bioavailable quantity of Vitamin K, which is important for bone and circulatory health.
Minerals: A Wealth of Essential Elements
Beyond vitamins, liver is a top-tier source of vital minerals. The minerals found in liver are often in the highly bioavailable heme form, meaning the body can absorb and utilize them more efficiently than plant-based sources.
Iron
Liver is one of the best dietary sources of heme iron, a mineral that carries oxygen throughout the body in red blood cells. A 100g serving of chicken liver provides around 11.6mg of iron, while beef liver has slightly less at 6.5mg, both offering a substantial portion of the daily requirement. This is a key benefit for individuals at risk of iron-deficiency anemia.
Copper
Beef liver, in particular, is extremely high in copper, a trace mineral essential for energy production, iron metabolism, and brain function. A 100g portion can provide over 1,000% of the DV. This concentration requires careful moderation in consumption to prevent toxicity.
Selenium and Zinc
Liver contains excellent levels of selenium, an antioxidant that protects cells from damage, and zinc, which supports the immune system and metabolism.
Comparison: Beef Liver vs. Chicken Liver per 100g
While both offer dense nutrition, there are notable differences between common liver types. Below is a comparison of key nutrients per 100g (cooked):
| Nutrient | Beef Liver | Chicken Liver |
|---|---|---|
| Calories | ~191 kcal | ~172 kcal |
| Protein | ~29g | ~26g |
| Fat | ~5.3g | ~6g |
| Cholesterol | ~396mg | ~564mg |
| Iron | ~6.5mg (36% DV) | ~13mg (161% DV) |
| Vitamin B12 | ~71µg (2941% DV) | ~21µg (880% DV) |
| Vitamin A | ~9442µg (1049% DV) | ~4296µg (477% DV) |
| Copper | ~14mg (1587% DV) | ~1mg (59% DV) |
| Selenium | ~36µg (66% DV) | ~88µg (160% DV) |
Risks and Safe Consumption
Despite its benefits, liver must be consumed in moderation due to its high concentration of certain nutrients. Regular, excessive intake can lead to hypervitaminosis A (Vitamin A toxicity), potentially causing bone weakness, headaches, and liver damage. Furthermore, due to its copper content, individuals with Wilson's disease should avoid it entirely. Liver is also high in cholesterol and purines, which can affect individuals with pre-existing conditions like gout. For most healthy adults, one serving of 100g per week is a safe and beneficial amount. The liver is the body's filter, but contrary to a common myth, it does not store toxins; rather, it accumulates nutrients used to process toxins. To minimize exposure to potential contaminants like antibiotics, sourcing liver from ethically raised, organic animals is recommended.
Conclusion
In summary, the nutritional value of liver per 100g is exceptionally high, providing a robust profile of protein, vitamins, and minerals that far surpasses most other foods. Its concentrated doses of Vitamin A, B12, and iron offer significant health advantages, from boosting energy to supporting immune function. However, this potency necessitates mindful consumption to avoid potential toxicity from excessive Vitamin A and copper. By enjoying liver in moderation and sourcing it carefully, it remains a valuable and nutrient-dense addition to a balanced diet.
Sources
- Healthline: 7 Healthy High-Cholesterol Foods
- WebMD: Is Eating Liver Good for You?
- Medical News Today: Beef liver: Nutrition, benefits, and risks
Keypoints:
- Macronutrients: A 100g serving of liver is very high in protein and low in carbohydrates, with a moderate amount of fat, making it a satiating and energy-dense food.
- Vitamin A: Liver is an unparalleled source of preformed Vitamin A, which supports vision, immunity, and cell growth, though excessive intake can be toxic.
- Vitamin B12: The amount of Vitamin B12 in 100g of liver is exceptionally high, vital for nerve function and red blood cell production.
- Heme Iron: As a potent source of heme iron, liver is highly effective at preventing and treating iron-deficiency anemia.
- Copper Content: Beef liver contains extremely high levels of copper, a critical mineral, but its concentration requires moderation to prevent toxicity.
- Moderation is Key: Due to its high concentration of Vitamins A and copper, a single 100g serving of liver per week is generally recommended for healthy adults.
- Sourcing Matters: For safe consumption, it is best to source liver from responsibly raised, organic animals to minimize potential exposure to contaminants.
Faqs: Q: Is it safe to eat liver every day? A: No, it is not safe to eat liver daily. Due to its extremely high levels of Vitamin A and copper, consuming liver daily can lead to a toxic buildup of these nutrients in your body, which can cause serious health issues.
Q: Is liver bad for people with high cholesterol? A: Liver is high in dietary cholesterol, and while dietary cholesterol's impact on blood cholesterol is less of a concern for many, those with high cholesterol or on cholesterol-lowering medication should consult their doctor and moderate their intake.
Q: Is it true that the liver stores toxins? A: No, this is a myth. The liver's function is to filter and process toxins for removal, not store them. Instead, the liver stores essential nutrients like vitamins and minerals.
Q: Which type of liver is the healthiest per 100g? A: While all types are nutritious, beef liver is often considered the most nutrient-dense overall due to its higher levels of various vitamins and minerals, though some types like chicken liver are higher in specific nutrients like iron.
Q: Is liver good for people with anemia? A: Yes, liver is an excellent food for individuals with iron-deficiency anemia, as it is a concentrated source of highly absorbable heme iron and Vitamin B12, which are crucial for healthy red blood cell production.
Q: Why should pregnant women avoid eating liver? A: Pregnant individuals are advised to limit or avoid liver due to its very high Vitamin A content. Excessive intake of preformed Vitamin A can have adverse effects on fetal development and may lead to birth defects.
Q: Can children eat liver? A: Yes, but in very small, carefully controlled amounts. Due to the high concentration of certain minerals, some studies advise limiting consumption for children to no more than once a week.
