Available year-round, lovers of calf's liver hold this food in very high regard not only for its tremendous storehouse of nutrients but for its delicious taste and texture.
Calf's liver is less likely to have the accumulations of toxins such as pesticides, hormones and antibiotics found in the liver of older animals. Selecting organic calf's liver provides the greatest assurance that the liver is free of these toxins. Calf's liver also is more tender and has better flavor than beef liver.
Calf's liver is an exceptionally nutrient-dense food as it is an excellent source of vitamin B12, vitamin A, copper, folate, riboflavin, and selenium; a very good source of zinc, vitamin C, protein, niacin, and phsophorus; and a good source of vitamin B5, vitamin B6 and iron. Although calf's liver is also high in cholesterol and saturated fat, its concentration of so many beneficial nutrients makes it an extremely healthful food. Here are some of the most important reasons why individuals who eat meat should make calf's liver a frequent choice.
Cardiovascular Benefits
First of all, calf's liver is a very good source of protein, providing 49.1% of the daily value for protein in just 4 ounces. In addition to being a very good source of protein, calf's liver is an excellent source of vitamin B12, folate, and riboflavin, as well as a very good source of niacin and a good source of vitamin B6.
Vitamin B12, B6 and folate are all needed by the body to convert the potentially dangerous chemical homocysteine into other, benign molecules. Since high homocysteine levels are associated with an increased risk of heart attack and stroke, getting plenty of B12, folate and B6 in your diet is important. In addition to these three B vitamins, a fourth B vitamin, riboflavin is needed since it is necessary for the proper functioning of B6. Without riboflavin's assistance, vitamin B6 cannot change into its active form.
But that's not the only reason to value riboflavin for cardiovascular health. Riboflavin is also a cofactor in the reaction that regenerates glutathione, one of the body's most important antioxidants. Among its many beneficial activities, glutathione protects lipids like cholesterol from free radical attack. Only after cholesterol has been damaged by free radicals does this fat-containing molecule pose a threat to blood vessel walls.
Lastly, niacin, yet another B vitamin with cardiovascular benefits, has been used for years to safely and effectively lower high cholesterol levels, which is also important in atherosclerosis and diabetic heart disease.
A four-ounce serving of calf's liver provides an amazing 689.8% of the daily value for vitamin B12, 215.2% of the DV for folate, 129.4% of the DV for riboflavin, and 28.0% of the DV for B6, and 48.0% of the DV for niacin.
B Vitamins for Energy
As noted above in relation to its cardiovascular benefits, calf's liver is a very good source of niacin and a good source of vitamin B6. In addition, calf's liver is a good source of another B-vitamin, pantothenic acid. This particular mix of B-complex vitamins makes calf's liver a helpful food in supporting energy metabolism throughout the body, because these three vitamins are involved as cofactors that help enzymes throughout the body guide metabolic reactions.
All three B vitamins are important for energy production. Niacin is essential for the conversion of the body's proteins, fats, and carbohydrates into usable energy. Niacin helps optimize blood sugar regulation via its actions as a component of a molecule called glucose tolerance factor, which optimizes insulin activity. Vitamin B6 is essential for the body's processing of carbohydrate (sugar and starch), especially the breakdown of glycogen, the form in which sugar is stored in muscle cells and to a lesser extent in our liver. Pantothenic acid also plays an important role in the prevention of fatigue since it supports the function of the adrenal glands, particularly in times of stress. A four-ounce serving of calf's liver supplies 48.0% of the daily value for niacin, 28.0% of the DV for vitamin B6, and 25.9% of the DV for pantothenic acid.
Cancer Protection
Diets high in vitamin B12-rich foods, especially if they are low in fat, are also associated with a reduced risk of colon cancer. And, calf's liver is also an excellent source of selenium and a very good source of zinc. Selenium helps reduce the risk of colon cancer since it is needed for the proper function of glutathione peroxidase, an important internally produced antioxidant that not only protects the cells of the colon from free radicals and cancer-causing toxins, but has also been shown to reduce the severity of inflammatory conditions like asthma and rheumatoid arthritis. Selenium is incorporated at the active site of glutathione peroxidase, which is particularly important for cancer protection. Glutathione peroxidase is used in the liver to detoxify a wide range of potentially harmful molecules, which might otherwise wreak havoc on any cells with which they come in contact, damaging their cellular DNA and promoting the development of cancer cells. For this and other reasons, foods rich in selenium are also associated with a reduced risk for colon cancer. Accumulated evidence from prospective studies, intervention trials and studies on animal models of cancer have suggested a strong inverse correlation between selenium intake and cancer incidence. Selenium has been shown to induce DNA repair and synthesis in damaged cells, to inhibit the proliferation of cancer cells, and to induce their apoptosis, the self-destruct sequence the body uses to eliminate worn out or abnormal cells. Just four ounces of calf's liver supplies more than 82.6% of the daily value for selenium. Calf's liver is also a very good source of zinc, which along with vitamin A, another nutrient for which calf's liver is an excellent source, is essential for the health of epithelial tissues, including the endothelium--the lining of the blood vessels. These two nutrients provide another way in which calf's liver can help to prevent the blood vessel damage that occurs in atherosclerosis. Four ounces of calf's liver provide way more than 100% of the daily value for vitamin A-609.7% in fact, plus 72.0% of the daily value for zinc. Protection against Emphysema If you or someone you love is a smoker, or if you are frequently exposed to secondhand smoke, then making vitamin A-rich foods, such as calf's liver, part of your healthy way of eating may save your life, suggests research conducted at Kansas State University. While studying the relationship between vitamin A, lung inflammation, and emphysema, Richard Baybutt, associate professor of nutrition at Kansas State, made a surprising discovery: a common carcinogen in cigarette smoke, benzo(a)pyrene, induces vitamin A deficiency. Baybutt's earlier research had shown that rats fed a vitamin A-deficient diet developed emphysema. His latest animal studies indicate that not only does the benzo(a)pyrene in cigarette smoke cause vitamin A deficiency, but that a diet rich in vitamin A can help counter this effect, thus greatly reducing emphysema. In his initial research, Baybutt took just weaned male rats and divided them into two groups, one of which was exposed to cigarette smoke, and the other to air. In the rats exposed to cigarette smoke, levels of vitamin A dropped significantly in direct correlation with their development of emphysema. In the second study, both groups of rats were exposed to cigarette smoke, but one group was given a diet rich in vitamin A. Among those rats receiving the vitamin A-rich foods, emphysema was effectively reduced. Baybutt believes vitamin A's protective effects may help explain why some smokers do not develop emphysema. "There are a lot of people who live to be 90 years old and are smokers," he said. "Why? Probably because of their diet…The implications are that those who start smoking at an early age are more likely to become vitamin A deficient and develop complications associated with cancer and emphysema. And if they have a poor diet, forget it." If you or someone you love smokes, or if your work necessitates exposure to second hand smoke, protect yourself by making sure that at least one of the World's Healthiest Foods that are rich in vitamin A, such as calf's liver, is a daily part of your healthy way of eating.(October 21, 2004)
Optimizing Immune Function
The large dose of vitamin A and zinc supplied by a serving of calf's liver can significantly help immune system function. Vitamin A is critically important for the health of epithelial and mucosal tissues, the body's first line of defense against invading organisms and toxins. The epithelium is a layer of cells forming the epidermis of the skin and the surface layer of mucous and serous membranes. All epithelial surfaces including the skin, vaginal epithelium, and gastrointestinal tract rely upon vitamin A. When vitamin A status is inadequate, keratin is secreted in epithelial tissues, transforming them from their normally pliable, moist condition into stiff dry tissue that is unable to carry out its normal functions, and leading to breaches in epithelial integrity that significantly increase susceptibility to the development of allergy and infection.
So, when our vitamin A levels are low, we are much more susceptible to infections such as recurrent ear infections or frequent colds, or we may wind up with an immune system that is overactive, leading to autoimmune diseases like rheumatoid arthritis. In fact, low vitamin A levels in Third World countries are blamed for the huge amounts of complications and deaths due to childhood diseases like measles. When children in these areas are given adequate amounts of vitamin A, the number of deaths from these illnesses drops dramatically, just one demonstration of the importance of vitamin A for strong immune function.
Zinc, the most critical mineral for immune function, acts synergistically with vitamin A, promotes the destruction of foreign particles and microorganisms, protects against free-radical damage, is required for proper white cell function, and is necessary for the activation of serum thymic factor--a thymus hormone with profound immune-enhancing actions. Zinc also inhibits replication of several viruses, including those of the common cold.
Calf's liver's supply of these two nutrients alone provide reason enough to rely on this healthful food for immune support, but the same four-ounce serving of calf's liver also contains 58.6% of the daily value for vitamin C.
One of the best known antioxidant and immune supportive nutrients, vitamin C is vital for the proper function of the immune system. The primary water-soluble antioxidant in the body, vitamin C disarms free radicals, thus preventing damage in the aqueous environment both inside and outside cells. Inside cells, a potential result of free radical damage to DNA is cancer. Especially in areas of the body where cellular turnover is especially rapid, such as the digestive system, preventing DNA mutations translates into preventing cancer. This is why a good intake of vitamin C is associated with a reduced risk of colon cancer.
Free radical damage to other cellular structures and other molecules can result in painful inflammation, as the body tries to clear out the damaged parts. Vitamin C, which prevents the free radical damage that triggers the inflammatory cascade, is thus also associated with reduced severity of inflammatory conditions, such as asthma, osteoarthritis, and rheumatoid arthritis.
Free radicals also oxidize cholesterol. Only after being oxidized does cholesterol stick to the artery walls, building up in plaques that may eventually grow large enough to impede or fully block blood flow, or rupture to cause a heart attack or stroke. Since vitamin C can neutralize free radicals, it also helps prevent the oxidation of cholesterol.
Minerals that Support Energy Production, Bones, Blood Vessels and Colonic Health
Calf's liver is also an excellent source of copper and a good source of iron.
Copper is an essential component of the enzyme, superoxide dismutase, which is important in energy production and antioxidant defenses. Copper is also necessary for the activity of lysyl oxidase, another enzyme that is involved in cross-linking collagen and elastin, both of which provide the ground substance and flexibility in blood vessels, bones and joints. Copper's involvement in both antioxidant defense and joint tissue production may be why people with rheumatoid arthritis find copper helpful for relieving some of their symptoms. Low dietary intake of copper may also be associated with increased fecal free radical production and fecal water alkaline phosphatase activity, risk factors for colon cancer. Iron is primarily used as part of hemoglobin, the molecule responsible for transporting and releasing oxygen throughout the body. But hemoglobin synthesis also relies on copper. Without copper, iron cannot be properly utilized in red blood cells. Fortunately, Mother Nature supplies both minerals in calf's liver; a four-ounce serving provides 450.5% of the daily value for copper, along with 16.5% of the DV for iron. Calf's liver is also a very good source of zinc. In addition to maintaining prostate health, another reason for older men to make zinc-rich foods, a regular part of their healthy way of eating is bone mineral density. Although osteoporosis is often thought to be a disease for which postmenopausal women are at highest risk, it is also a potential problem for older men. Almost 30% of hip fractures occur in men, and 1 in 8 men over age 50 will have an osteoporotic fracture. A study of 396 men ranging in age from 45-92 that was published in the September 2004 issue of the American Journal of Clinical Nutrition found a clear correlation between low dietary intake of zinc, low blood levels of the trace mineral, and osteoporosis at the hip and spine. (October 18, 2004)
Lovers of calf's liver hold this food in very high regard. This is not just because the liver from a baby cow is a storehouse of nutrients, but because it also has a delicious taste and delicate texture.
In Latin, the scientific name for cow (the source of calf's liver) is Bos taurus.
Cows and calves were first domesticated for beef in the regions of Greece and Turkey about 4,000 years ago. It was not only the muscular parts (the meat) of cows and calves that were consumed, but also the organs, including the liver. Cows and the food that they provide have been revered in many civilizations throughout history, even being considered sacred in India and some parts of Africa.
Today, calf's liver is part of many different cuisines throughout the world. In European countries, including Italy, France, Austria and Germany, it is considered a delicacy. Fegato alla Veneziana (liver and onions) is one of the most famous dishes in the culinary history of Venice, Italy. Calf's liver also plays an important role in Jewish cooking with chopped liver being a very popular and traditional food in this cuisine.
There are a few clues you can look for that will help you choose fresher quality calf's liver. Always examine the sell-by date on the label and choose that with the latest date. Calf's liver should be shiny in appearance and have a pleasant smell.
It is very important to purchase calf's liver that was from an organically raised animal. Because the liver is the body's primary organ for disabling toxic substances, more toxic substances are often found in the liver than in any other body part. Buying organic calf's liver will give you more assurance that the liver you are feeding yourself and your family does not have accumulated toxins, including pesticides, hormones or antibiotic residues. Buying organic will also increase the likelihood that animals were raised in a more humane manner.
Since calf's liver is very perishable, it should always be kept at cold temperatures, either refrigerated or frozen. Refrigerate the calf's liver in the original store packaging, if it is still intact and secure, as this will reduce the amount of handling involved. Calf's liver will keep in the refrigerator for only one or two days.
If you will not be able to cook the liver within one or two days of purchase, you can freeze it in a cold temperature freezer. Using either aluminum foil or freezer paper, wrap the calf's liver carefully so that it is as tightly packaged as possible. It should be able to keep for three to four months in the freezer.
Tips for Preparing Calf's Liver:
In order to ensure even cooking, cut the liver into even sized pieces. Do not overcook the liver because it will tend to become very tough and fibrous.
A Few Quick Serving Ideas:
Braise calf's liver and mushrooms in red wine.
Healthy sauté calf's liver and onions.
Mix together cooked calf's liver, boiled eggs and healthy sautéed onions to make chopped liver spread.
Calf's Liver and Purines
Purines are naturally-ccurring substances found in plants, animals, and humans. In some individuals who are susceptible to purine-related problems, excessive intake of these substances can cause health problems. Since purines can be broken down to form uric acid, excess accumulation of purines in the body can lead to excess accumulation of uric acid. The health condition called "gout" and the formation of kidney stones from uric acid are two examples of uric acid-related problems that can be related to excessive intake of purine-containing foods. For this reason, individuals with kidney problems or gout may want to limit or avoid intake of purine-containing foods such as calf's liver.
Special Handling of Calf's Liver
Special safety precautions are important when handling calf's liver. However, the following recommendations should be used as guidelines when handling any animal flesh involved in a meal.
When you are at the grocery store, purchase calf's liver last. Since raw meats contaminate other grocery items, keep fresh calf's liver apart from other items. Put calf's liver in a plastic bag, so juices won't drip onto other foods.
Store the calf's liver separately from cooked foods, and refrigerate or freeze it immediately after bringing it home. Never leave calf's liver in a hot car or sitting out at room temperature. Packaged calf's liver may be refrigerated in its original wrapping in the coldest part of the refrigerator (usually the bottom back) for three to five days after purchase.
Always wash your hands thoroughly with hot soapy water before preparing foods and after handling calf's liver. Don't let the calf's liver or its juices touch ready-to-go foods, either in the refrigerator or during preparation. Don't put cooked foods on the same plate that held the calf's liver. Always wash utensils that have touched the calf's liver with hot, soapy water before using them for cooked meats. Wash counters, cutting boards and other surfaces any raw meat may have touched. These surfaces may be sanitized by cleaning with a solution of 1 teaspoon chlorine bleach per quart of water.
Never brown or partially cook calf's liver, then refrigerate and finish cooking later, because any bacteria present would not have been destroyed and can multiply.
The Importance of Organic Calf's Liver
Also, as previously explained under How to Select and Store, it is particularly important to select liver from an organically-fed animal.
Calf's liver is an excellent source of the minerals copper and selenium as well as an excellent source of vitamin A, vitamin B2, vitamin B12 and folate. In addition, it is also a very good source of protein, vitamin C, zinc, niacin and phosphorous and a good source of vitamin B5, vitamin B6, and iron.
Introduction to Food Rating System Chart
The following chart shows the nutrients for which this food is either an excellent, very good or good source. Next to the nutrient name you will find the following information: the amount of the nutrient that is included in the noted serving of this food; the %Daily Value (DV) that that amount represents; the nutrient density rating; and the food's World's Healthiest Foods Rating. Underneath the chart is a table that summarizes how the ratings were devised.| Calf's liver, braised 4.00 oz-wt 113.40 grams 187.11 calories | ||||
| Nutrient | Amount | DV (%) | Nutrient Density | World's Healthiest Foods Rating |
|---|---|---|---|---|
| vitamin B12 (cobalamin) | 41.39 mcg | 689.8 | 66.4 | excellent |
| vitamin A | 30485.26 IU | 609.7 | 58.7 | excellent |
| copper | 9.01 mg | 450.5 | 43.3 | excellent |
| folate | 860.70 mcg | 215.2 | 20.7 | excellent |
| vitamin B2 (riboflavin) | 2.20 mg | 129.4 | 12.4 | excellent |
| selenium | 57.84 mcg | 82.6 | 7.9 | excellent |
| tryptophan | 0.25 g | 78.1 | 7.5 | excellent |
| zinc | 10.80 mg | 72.0 | 6.9 | very good |
| vitamin C | 35.16 mg | 58.6 | 5.6 | very good |
| protein | 24.53 g | 49.1 | 4.7 | very good |
| vitamin B3 (niacin) | 9.61 mg | 48.0 | 4.6 | very good |
| phosphorus | 361.75 mg | 36.2 | 3.5 | very good |
| vitamin B6 (pyridoxine) | 0.56 mg | 28.0 | 2.7 | good |
| vitamin B5 (pantothenic acid) | 2.59 mg | 25.9 | 2.5 | good |
| iron | 2.97 mg | 16.5 | 1.6 | good |
| World's Healthiest Foods Rating | Rule | ||||
|---|---|---|---|---|---|
| excellent | DV>=75% | OR | Density>=7.6 | AND | DV>=10% |
| very good | DV>=50% | OR | Density>=3.4 | AND | DV>=5% |
| good | DV>=25% | OR | Density>=1.5 | AND | DV>=2.5% |
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