Critical Aspects of Health: The Liver and Gallbladder

We have been exploring in detail various bodily systems and nutritional solutions for maintaining the optimal functioning of these systems. Previously, we explored the immune system, the male and female reproductive systems, the gastrointestinal tract, the HPA axis, bones and joints, the visual system and the urinary tract. This month, we will discuss the liver and gallbladder as structures of the digestive system, situations leading to the inefficient functioning of those structures, and the use of key nutraceuticals to help promote healthy liver and gallbladder function.

The Structure and Function of the Liver

Not only is the liver the largest organ in the body, but also it is unquestionably one of the most vital to survival. Hepatocytes or liver cells make up this triangular hepatic organ (from the Greek word for liver, hēpar). The liver has four lobes of unequal size and shape, is reddish brown in appearance, and weighs between 3.2–3.7 lbs. Located in the right upper quadrant of the abdominal cavity, the liver is positioned just below the diaphragm, to the right of the stomach and overlaying the gallbladder. It is connected to two large blood vessels, one called the hepatic artery and one called the portal vein. The hepatic artery supplies arterial blood to the liver, while the portal vein carries venous blood drained from the spleen, gastrointestinal tract and its associated organs.¹

Bile produced in the liver is collected in thin tubes (i.e., bile canaliculi), which merge to form bile ducts. These ducts eventually drain into hepatic ducts, which merge to form the common hepatic duct. The common bile duct is formed by the common hepatic duct and the cystic duct from the gallbladder.¹

The liver has a wide range of functions. Arguably, the most important of these is to filter the blood coming from the digestive tract, before passing it to the rest of the body. Other functions include:

• Playing a large role in the synthesis of amino acids
• Playing a large role in protein metabolism, synthesis and degradation
• Playing a large role in the production of thrombopoietin production (a glycoprotein hormone that regulates the production of platelets by the bone marrow)
• Synthesizing glucose from amino acids, lactate or glycerol (i.e. gluconeogenesis)
• Synthesizing angiotensinogen
• Synthesizing cholesterol
• Forming glycogen from glucose (i.e. glycogenesis, also take place in muscles)
• Producing triglycerides (i.e., lipogenesis)
• Producing coagulation factors
• Producing bile for fat emulsification
• Producing insulin-like growth factor 1 (IGF-1)
• Producing albumin
• Contributing toward the Phase I and II detoxification of toxins and xenobiotics
• Conversion of ammonia to urea
• Breaking down glycogen into glucose (i.e. glycogenolysis)
• Breaking down insulin and other hormones
• Storage of glycogen, vitamin A, vitamin D, vitamin B12, iron and copper¹

The Structure and Function of the Gallbladder

The gallbladder is a relatively small organ that concentrates bile sent to it from the liver, increasing bile potency. Situated immediately below the liver, this organ is about 3.1 inches in length and 1.6 inches in diameter when fully distended. It is divided into three sections; the fundus, the body and the neck. A mucosal fold called Hartmann’s pouch is present at the neck of the gallbladder and is often an area where bile stasis may occur.¹

The gallbladder can store about 50 milliliters of bile. The presence of food containing fat stimulates the secretion of the hormone cholecystokinin (CCK) by the intestinal mucosa, which in turn stimulates the release of bile from the gallbladder to help in the emulsification of dietary fat for digestive purposes.¹

Suboptimal Functioning of the Liver and Nutraceutical Compensation

There are circumstances in which the liver functions suboptimally. Several factors can play a role in this including an unbalanced inflammatory response and oxidative stress to liver tissue. In these instances, specific nutraceuticals may help to promote healthy functioning of the liver.

Imbalanced fat metabolism in the liver may occur when the liver is overburdened and is unable to efficiently detoxify substances resulting from dietary or environmental exposure. Data suggests that easily one-third of all American adults have imbalanced fat metabolism in the liver. Unfortunately, it often causes no signs and symptoms, and sometimes no complications. In some cases, however, the accumulation of fat can result in an imbalanced inflammatory response and impact liver function.² Inefficient liver fat metabolism is often discovered via incidentally elevated liver enzyme levels. There is a strong association with it and being overweight. It can also ultimately impact the efficiency of insulin function.

Milk Thistle has been used for centuries to promote healthy liver function. Pliny the Elder, a Roman Naturalist, described Milk Thistle as being “excellent for carrying of bile.”³ Modern research has revealed that a group of flavonolignans, collectively called silymarin, are considered to be the active compounds in Milk Thistle offering hepatoprotective effects.³ These effects are accomplished via several mechanisms, including antioxidation,⁴ inhibition of lipid peroxidation,⁵ promoting liver detoxification via phase I and II detoxification and glucuronidation,^6-8 and protection of glutathione depletion.⁹ Furthermore, Milk Thistle, combined with vitamin E and phospholipids, has supported liver health and enhanced liver function parameters as demonstrated in a pilot study.^10-11

In addition to Milk Thistle, animal data suggests that beets may be effective against fat deposition in the liver,¹² and trimethylglycine is capable of keeping the liver healthy and enhancing liver fat processing.¹³ Also, animal research has shown that N-acetyl cysteine (NAC) can improve liver fat metabolism, while lipoic acid is an effective antioxidant that can enhance lipid processing by hepatic cells.^14-15

A Healthy, Balanced Hepatic Inflammatory Response

An imbalanced inflammatory response may occur throughout the body due to a broad variety of lifestyle factors, and the liver is certainly not immune to this occurrence. When out of balance, this response may contribute to inefficient liver detoxification. The etiology of hepatic inflammation may be related to toxins and chemicals resulting from dietary or environmental exposures, including alcohol, certain medications, some industrial organic solvents and some plants.

Studies have shown silymarin to be effective for helping to support healthy hepatic inflammatory balance while promoting healthy levels of serum bilirubin, AST, ALT and serum liver enzymes.¹⁷ Research has also demonstrated that supplementation with vitamin B1 and vitamin B12 (with or without folic acid) help maintain balanced hepatic inflammatory responses.^18-20 Other research²¹ suggests that lipoic acid along with milk thistle and other nutraceuticals promoted significant improvements in liver function and overall health.

Supporting Healthy Liver Tissue

Promoting optimal liver health requires a combination of healthy lifestyle factors and consumption of a diet rich in fruits and vegetables. Several herbs and nutrients taken as supplements can also help maintain optimal liver detoxification capacity. European clinical studies have demonstrated that silymarin administration promoted healthy levels of serum liver enzymes and total bilirubin, while supporting healthy liver tissue histology in individuals with excess exposure to dietary toxins.²² Additional research suggests that administration of silymarin also supported a healthy lifespan.²³ Like Milk Thistle, research has shown that Artichoke leaf extract also has hepatoprotective effects.^24-27 The phosholipid, phosphatidylcholine (PC), has been shown to help optimize liver function and enhance hepatic cellular health and healing.²⁸ Animal research further suggests that PC can help promote efficient liver function.^29-31 In a controlled human trial, PC supplementation was found to promote healthy liver function in people requiring detoxification support.³²

Suboptimal Functioning of the Gallbladder and Nutraceutical Compensation

Suboptimal functioning of the gallbladder may occur as the result of bile stasis, and a gallbladder inflammatory response. In these instances, specific nutraceuticals may help to promote healthy functioning of the gallbladder.

Excess cholesterol deposits in the gallbladder can lead to bile stasis when metabolism of lipids is inefficient. Similarly, stasis or reduced flow may also occur with excessive amounts of bilirubin. Such reduction in bile flow is more likely to occur when the gallbladder does not effectively empty bile (such as during pregnancy), in the case of regeneration of liver tissue, and as the result of rapid weight loss, particularly occurring from eating a very low-calorie diet.¹⁶

One part of the nutraceutical approach to supporting healthy gallbladder function includes promoting the healthy flow of bile. Artichoke has a similar effect to Milk Thistle with regard to stimulating bile flow, which has been demonstrated in several studies.³³ In addition, Dandelion root extract has been shown to act as a cholagogue, promoting the flow of bile.³⁴ Other nutraceutical approaches include the use of phosphatidylcholine, vitamin C, magnesium and taurine. Phosphatidylcholine has been found to enhance bile flow and prevent gallbladder inefficiency in both animal and human research.^35-37 The mechanism of action seems to be phosphatidylcholine’s beneficial effect on cholesterol solubility and crystallization.^38-39 Women who have higher blood levels of vitamin C are less likely to form gallbladder deposits. This may be due to the fact that vitamin C helps convert cholesterol to bile acids.^40-42 Vitamin C supplementation was also shown to improve a parameter associated with reduced likelihood of forming gallbladder deposits.⁴³ Likewise, low intakes of magnesium have also been implicated in the formation of gallbladder deposits.⁴⁴ In addition, taurine is involved in bile acid conjugation and healthy bile production.⁴⁵

Healthy Gallbladder Inflammatory Response

Any issues with bile stasis or inefficiency may result in an imbalanced inflammatory response in the gallbladder, which is characterized by poor bile flow and retention of bile.¹⁶ Supplementary nutrients that support both liver and gallbladder efficiency are indicated when such a situation presents itself. These nutrients can ensure that both liver and gallbladder health and function is optimized.

Dietary Supplements for Healthy Liver & Gallbladder Function

As previously discussed, healthy function of the liver and gallbladder may be promoted with key nutraceuticals. Table 1 lists those nutraceuticals and the two products, Liver Support Formula™ and Gallbladder Formula, which provide them. Both products provide nutraceuticals that are beneficial for the liver and gallbladder, so both products may be used concurrently.

Conclusion

The liver performs multiple roles in the body, and the gallbladder stores and concentrates bile for fat digestion. In some circumstances, suboptimal function of these structures may occur. Research has demonstrated that key nutraceuticals may help promote healthy functioning of the liver and gallbladder.

References

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