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Liver Health 25 August 2009

It is crucial we maintain our liver in optimal health. The main functions of the liver include:

• detoxification
• cholesterol control
• blood sugar control
• hormone and enzyme production
• immunity
• metabolism of food
• protein synthesis
• production of anabolic repair chemicals.

No health program will work well if the liver is not in top shape. Unfortunately it is constantly assaulted by alcohol, caffeine, drugs, food additives, viruses and environmental toxins. Toxins (known as xenobiotics) can range from car exhaust and amines produced from barbecueing meat to dry cleaning chemicals and xenoestrogens in plastic wraps.

The liver is the body’s main way of detoxifying xenobiotics as well as intrinsic toxins formed from metabolism. Understanding how the liver does this is crucial to maintaining an optimally functioning liver. The liver is actually made up of rows of cells separated by fluid spaces through which blood flows. This system acts as a filter removing dead cells, microorganisms, chemicals and drugs. After filtration, the liver then detoxifies the chemicals. Essentially this is a two-step process, known as Phase 1 and Phase 2. Most environmental toxins are fat soluble which means they dissolve only in oily solutions such as fat tissues and cell membranes and not water. This makes it hard for the body to eliminate them and they can be stored there for years. Organs particularly effected are the brain and endocrine organs. Neurological disorders and hormonal imbalances can therefore occur with environmental toxin accumulation. Many of the toxins are carcinogenic and can lead to cancer.

The two phases together are designed to convert fat soluble toxins into water soluble molecules that can be excreted in the urine and bile. Unfortunately, the molecules produced during Phase 1 can actually be more toxic than the original molecules. This is because the chemicals added to the original molecules enable the Phase 1 products to act like free radicals in the liver. As long as Phase 2 is functioning well, the potentially damaging Phase 1 products are quickly converted into harmless molecules and excreted. Phase 2 adds another molecule such as cysteine, glycine or sulphur to the Phase 1 compound to render it both harmless and water soluble. Illness develops if there is a problem with either phase because the body cannot detoxify appropriately. Both phases become less efficient with age. There are also some people who are either genetically rapid or slow metabolisers. Nutritional deficiencies and liver pathology can also interfere with either phase. The main enzyme system responsible for Phase 1 detoxification is known as the Cytochrome P-450 system. Excessive toxic chemicals such as pesticides can disrupt this enzyme system and actually increase its activity, resulting in large amounts of damaging free radicals being produced. Other chemicals causng an increase in Cytochrome P-450 activity include caffeine, alcohol, dioxin, organophosphates, paint fumes and exhaust fumes. Maximising the efficiency of the livers detoxification phases is crucial for health and vitality. There is no point in having youthful levels of anabolic hormones, if the organ which carries out their anabolic instructions is not working properly. Remember that liver function tests commonly ordered by your doctor don’t actually measure liver function — they measure levels of enzymes released by damaged liver cells. You can be a long way down the track of disordered function before you will ever see any evidence of cellular damage.

The progressive levels of liver damage look something like this:

1. Normal liver function.
2. Mildly abnormal liver function.
3. Severely abnormal liver function.
4. Fatty liver.
5. Mildly abnormal cellular damage.
6. Severely abnormal liver damage.
7. Cirrhosis.
8. Liver cancer.

So a person will be at level 4 before even registering as having a liver problem on a routine blood test and usually it’s actually at level 5 before any action is taken. If you really want to know how your liver is functioning, some laboratories do a “functional liver detoxification profile“ (FLDP) which is a much better test.

Maintaining a healthy liver is not complicated. As discussed, the liver essentially works as ais a large filter followed by detoxification. Long-term health of any filter is dependent upon reducing the amount of debris filtered and regular cleaning. To optimise liver function:

1. Minimise alcohol consumption. That’s a maximum of one drink per day. If you have impaired liver functioning, avoid alcohol altogether.
2. Avoid hepatitis.
3. Reduce exposure to pollutants, pesticides and herbicides. Many of the common herbicides depress the function of cytochrome P450 and other enzymes crucial for detoxification.
4. Consume a largely plant based diet and use organic fruit and vegetables. Reduce consumption of refined carbohydrates, deep fried and processd foods.
5. Avoid coffee.
6. Minimise prescription drug use and avoid recreational drugs.
7. Regularly cleanse the liver (see cleansing fast).

There are many products on the market promising to cleanse and improve liver function. While this is a good idea, the liver is a complex organ and no one liver supplement can do this. The liver is a complex organ with many different phases to its function. Many products, while good for improving one phase 1 of liver detoxification will have no effect or actually make Phase 2 worse. Nutrients specifically required for Phase 1 detoxification include vitamins E, C and the B group, glutathione and caretenoids. Specifically required for Phase 2 include the amino acids glutamine, glycine, taurine, cysteine and organic sulphur compounds (such as eggs, garlic, onions and broccoli).

A cleansing fast will always help the liver but I always suggest a FLDP before any long term liver supplementation so it can be focused and specific. Common liver support products I may use for which there is good evidence for include milk thistle, silymarin (an extract of milk thistle), goji, schizandra, rhodiola rosea, DHEA and N-acetyl-cysteine. Brocolli extract has also been shown to increase production of Phase 2 detoxification and antioxidant enzymes. Glutathione is the body’s chief intrinsic antioxidant and is responsible for much of the liver’s detoxification function. Several amino acids have been shown to increase glutathione levels (glutamic acid, cysteine and glycine) and some herbs increase its activity, particularly curcumin. For more information on glutathione, see Free Radicals.