The liver is the largest gland in the human body. Located behind the lower ribs on the right side of the abdomen, in healthy adults it weighs about 3 pounds and is roughly the size of a football. At any moment in time, it holds about 13% of the total blood supply, and yet we still do not fully understand all that this organ does for us or exactly how it does it.
More than 500 functions have been identified to date, for example:
* Filtering and refining ingested substances
* Storing iron and certain vitamins, minerals, and sugars
* Removing bacteria from the bloodstream
* Neutralizing and destroying poisonous substances, such as converting ammonia to urea
* Maintaining hormonal balance and blood glucose levels
* Regulating transport of chemicals and nutrients used by the body for energy
* Controlling blood clotting
* Managing production and excretion of cholesterol
* Serving as the main organ of blood formation before birth
* Regenerating its own damaged tissue (the liver is the only organ to do so)
* Producing bile, which enables the digestion of fats
The liver is soft and solid in consistency, dark reddish-brown, and indispensable to life. It is uniquely positioned between the intestines and the heart in such a way that all blood, thick with nutrients, bacteria, and potential toxins from the digestive process, passes through the liver before being sent to the heart for general circulation.
Here, in our chemical processing plant, everything we eat (except for long-chain fatty acids) is processed into the essential chemicals of life. Toxins are removed and converted so that they can be eliminated. Bile is produced to be stored in the gallbladder for use later in processing fats and fat-soluble vitamins (A, D, E, and K).
Internally, the liver has more than 100,000 hepatic lobules, each of which is a small six-sided structure composed of cells (hepatocytes) packed in slabs.
Eighty-five to ninety percent of all blood that leaves the stomach and intestines carries ingested substances directly to the liver, where macrophages (Greek for “big eaters”) or Kupffer cells remove large amounts of debris and bacteria. In the liver, drugs are chemically modified, thus defining the system’s reaction to them.
Liver Diseases
Because the liver is our body’s central refinery, it is affected by ingested chemicals whether they are prescription drugs, street drugs, or an over-the-counter product. In fact, almost every known pharmaceutical has, at one time or another, been implicated as a cause of liver damage. Every drug, industrial solvent, and pollutant, whether inhaled or swallowed, presents a challenge to our metabolism, sometimes resulting in damage to the liver.
Chemicals that damage the liver fall into two groups: predictable toxins and unpredictable ones. Predictable liver toxins regularly cause damage after exposure of a certain strength or duration in a large percentage of the population.
Unpredictable toxins cause damage in only a small percentage of the general public or in people with existing liver disease. Unpredictable damage appears to result from an allergic reaction that targets liver cells. A surprisingly large number of prescription drugs that are considered safe and currently in general use have been shown to cause significant liver damage in some people.
Predictable damage seems to be the result of ingestion of certain chemicals, specifically those that are difficult for the kidneys to excrete. The liver tries to clean up the blood by modifying those chemicals. During the process, other more dangerous toxins are formed and they then attack the liver and damage the cells. Injury can range from destruction of a few cells, which the liver can usually replace, to sudden and acute liver failure that calls for immediate hospitalization and eventual liver transplantation. Examples of known predictable liver toxins are the cleaning solvent carbon tetrachloride and the pain killer acetaminophen.
Acetaminophen is present in many over-the-counter and prescription drugs (e.g., Tylenol[R], Nyquil[R], Excedrin[R]) and is safe for most people when taken as prescribed. When it is taken in excess or over a long period of time, however, serious liver damage is the predictable result. Acetaminophen is toxic at lower doses in individuals who regularly consume more than two drinks a day or in those who may experience an allergic reaction.
Excessive exposure to certain other chemicals, in particular synthetic hormones or steroids, can result in a tumor, an abnormal mass of tissue that forms when cells begin to reproduce at an uncontrolled rate. Of course, the liver can be invaded by both noncancerous (benign) and cancerous tumors; in fact, benign tumors are quite common and usually produce no symptoms.
There are several types of benign tumors, including hepatocellular adenoma, which occurs most often in women of childbearing age and is associated primarily with the use of oral contraceptives, and hemangioma, a mass of abnormal blood vessels. Up to 5 percent of adults are believed to have small liver hemangiomas that are asymptomatic and require no treatment. Cancerous tumors are discussed later.
The U.S. Food and Drug Administration (FDA) Center for Drug Evaluation hosts notes from an international conference that focused on the problem of drug-induced liver injury. Authorities discussed drug testing by pharmaceutical companies, recommending more stringent controls over the testing, marketing, and releasing of pharmaceuticals to the general public, including better drug labeling in order to combat what is cited as a growing national and international problem.
Street Drugs and Alcohol
Illegal drug users and those who consume excessive amounts of alcohol (more than two drinks a day) represent the population group most at risk for life-threatening liver damage. Among the most prevalent liver diseases in this group are hepatitis and alcoholic cirrhosis.
Each year more than 25,000 Americans die of cirrhosis of the liver. It is the seventh leading cause of death in the United States in those between ages 25 and 44 years. Cirrhosis is a chronic disease marked by the gradual destruction of liver tissue, which is slowly replaced with scar tissue. As a result, levels of nutrients and hormones are progressively diminished, filtering of drugs and poisons is inhibited, and production of protein and other vital life substances is blocked.
Almost all serious disorders of the liver cause the same set of symptoms. The most common include (but are not limited to):
* Abnormal nerve function, sleep disturbances, and mental confusion
* Prolonged generalized itching
* Breast enlargement in men
* Abdominal pain or coughing up or vomiting blood
* Curling of fingers
* Hair loss
* Jaundice
* Muscle loss or unusual change of weight (a decrease of more than 5 percent within two months)
* Poor appetite or fatigue or loss of stamina
* Redness of palms
* Salivary gland enlargement (visible in cheeks)
* Shrinking of testes and general loss of sex drive or performance
* Spider-like veins in the skin
Of course, not all liver disease is drug-induced or alcohol-induced. Other hepatic diseases include viral hepatitis, congenital liver defects, and autoimmune disorders, in which the two metabolic disorders are hemochromatosis (absorption of too much iron) and Wilson’s disease (retention of too much copper in the liver).
When Cancer Strikes
Although there is a much higher incidence of primary liver cancer (originating in the liver) in patients with a chronic liver disorder, in particular those with chronic hepatitis or cirrhosis, it is not the most common form of liver cancer.
Secondary cancer, by far the most common form, has spread from another organ. A metastatic tumor forms in the liver when large progressive tumors within other organs shed cells. These cells move throughout the body through the circulatory system or through the lymphatic system, often lodging in tiny capillaries. The liver, connected to or close to a number of primary organs, is most often infected by metastatic tumors.
Primary cancer is still somewhat of a mystery. It is associated with viral hepatitis and certain parasites, drugs, and environmental toxins. Each year, 1,000 Americans die of primary liver cancers, and chronic carriers of the hepatitis B or C virus are at increased risk. Also at risk are patients with cirrhosis, people exposed to aflotoxin, people over 60 years of age, those with a family history, and men (the risk for men is twice that for women).
Symptoms of both types of cancer include abdominal pain, weight loss, fever, jaundice, nausea and vomiting, and weakness or fatigue.
Diagnostic techniques may include medical examination and liver function tests, abdominal ultrasound, computed tomography (CT), hepatic arteriography (x-rays taken after a substance is injected into the hepatic artery), and liver biopsy. Magnetic resonance imaging (MRI), a diagnostic technique that provides a cross-sectional image of the organs with x-rays or radiation, is also used.
There are several treatment options. Which one your doctor recommends depends on one’s general health, overall liver function, and whether or not the cancer has spread.
Localized cancer (cancer that has not yet spread) is considered to be resectable (able to be surgically removed) or unresectable. When resectable cancer cells can be removed by surgery, there is no evidence that the cancer has spread and the liver is working well. Unresectable cancer cannot be removed, even though it has not spread, because of cirrhosis or other conditions that cause poor liver function or because of the location of the tumor or other health problems.
Orthodox treatment may include any of the following options and others not listed here:
* Radiofrequency ablation. The physician uses a special probe to kill cancer cells with heat.
* Percutaneous ethanol injection. The physician injects alcohol directly into the liver tumor to kill cells.
* Cryosurgery. The physician makes an incision into the abdomen and inserts a metal probe to freeze and kill cancer cells.
* Hepatic arterial infusion. The physician injects anticancer drugs directly into the blood supply to the cancerous area.
* Chemoembolization. The physician inserts a tiny catheter into an artery in the leg. Using x-rays as a guide, the physician moves the catheter into the hepatic artery. Anticancer drugs are injected into the artery, and tiny particles are used to block the flow of blood out of the liver to the heart through the artery. With blood flow blocked, the drug stays in the liver longer.
* Total hepatectomy with liver transplantation. If localized liver cancer is unresectable because of poor liver function, some patients may undergo liver transplantation.
* Chemotherapy and radiation. These measures are used for advanced cancer or cancer that cannot be treated in another way.
Ten Steps to a Healthy Liver
1. Avoid taking unnecessary medications. Be sure to discuss your medication and the health of your liver with your physician. A number of noninvasive liver function tests can be performed to monitor the liver’s reaction to medication.
2. Do not mix medicines without the advice of a physician.
3. Do not take street drugs, and do not drown your liver in alcohol
4. Drink water. When the kidneys are healthy, the liver has an easier job to do.
5. Be careful when using aerosol cleaners. Because the liver must detoxify what you breathe as well as what you eat, make sure that the area is well ventilated when you clean.
6. Be careful when you use bug sprays, paint sprays, and chemical sprays. Wear a mask, and watch what gets on your skin. Your liver also filters toxins that enter through your skin.
7. Eat a well-balanced, nutritionally adequate diet. In fact, proper nutrition is often the only remedy prescribed for mild liver disorders and is an absolute must for acute or chronic diseases.
8. Be careful of the latest fad diet. A diet with too much protein in particular makes more toxic ammonia in the system that the liver must turn into urea to eliminate.
9. Cut down on deep-fried and fatty foods, and minimize your consumption of smoked, cured, and salted foods, which are hard on the system. Try lemon juice instead of salt. Increase your intake of high-fiber foods.
10. Do your homework. Know what you are putting into your system, whether it is food or drugs or an herbal tea. Understand what the substance. or food does for, you, and understand what it does to your liver.