Non-Alcoholic Fatty Liver

Data suggest that easily one-third of all American adults have non-alcoholic fatty liver (NAFL), yet it is virtually never discussed in the media for the epidemic that it is—although scientific literature is rife with research examining this condition. For example, in 2,287 subjects from a multiethnic, large urban population sample, nearly one-third of all Americans had NAFL, with prevalence differing among ethnic groups: 45 percent in Hispanics, 33 percent in whites, and 24 percent in blacks.¹ The higher prevalence in Hispanics was due to the higher incidence of obesity and insulin resistance. The prevalence of NAFL was also greater in men than women among whites (42 percent in men; 24 percent in women), but not in blacks or Hispanics. Likewise, in another study of 328 outpatients (18 to 70 years old) from an army medical center, NAFL was prevalent in 46 percent of subjects.²

In addition, there is a greater prevalence of NAFL among diabetics. This was in a study of 2,839 type 2 diabetic outpatients, where the unadjusted prevalence of NAFL was 69.5 percent, and increased with age: 74.6 percent among those aged 60 years or older.³ The age-adjusted prevalence for non-alcoholic fatty liver was 71.1 percent in men and 68 percent in women.³

Although nonalcoholic fatty liver is more prevalent in adults, it is still relatively common for children to have NAFL as well. A study conducted in San Diego county, California found that NAFL was present in 8.1 percent of an estimated 62,827 children age 2-19, adjusted for age and gender.⁴

Clearly, this under-recognized condition is of concern to a substantial percentage of the population. This article will introduce non-alcoholic fatty liver, its symptoms, prevalence, diagnosis and dietary supplements that may be used to promote healthy liver function.

The Liver: Its Crucial Role in Health

The liver is vital to human health, arguably performing the most diverse roles of any single organ. Among its myriad of functions, the liver plays a primary role in the detoxification of exogenous and endogenous biochemicals, including xenobiotic toxins and steroid hormones.^5-7 The liver synthesizes proteins, glucose (from amino acids), glycogen, triglycerides, cholesterol and coagulation factors, as well as stores certain vitamins (A, D and B12), minerals (iron and copper) and glycogen.⁸ This 3.1-3.5 pound organ produces bile, which is necessary to emulsify fats as part of the digestive process. Bile also serves as a vehicle for disposing of toxic molecules that are too large for disposal via urine.^9-10 In addition, the liver’s elegantly specialized tissues are involved in the regulation of a broad variety of high-volume biochemical reactions.¹¹

Given the liver’s multiple and irreplaceable functions, it is clear that interference with liver anatomy and physiology could have devastating effects upon systemic health and wellness. Such is the case with nonalcoholic fatty liver.

Nonalcoholic Fatty Liver

Nonalcoholic fatty liver describes the accumulation of fat in the liver of people who drink little or no alcohol. Unfortunately, NAFL is common, often causes no signs and symptoms, and sometimes no complications. In more serious cases, however, the fat that accumulates in NAFL can cause liver inflammation and scarring. Ultimately, at its most severe, NAFL can progress to liver failure.¹²

NAFL is often discovered via incidentally elevated liver enzyme levels. There is a strong association with NAFL, obesity and insulin resistance. Currently, NAFL is considered by many as the hepatic component of the metabolic syndrome.¹³

Symptoms and Causes

Although most NAFL patients are asymptomatic, there are symptoms that may be common. These include malaise, fatigue and discomfort in the right upper quadrant or diffuse abdominal discomfort. An enlarged liver may also be found on clinical examination. Also, most (80 percent) of NAFL patients have associated features of metabolic syndrome,¹⁴ which may include the presence of two or more of the following:

• Impaired glucose tolerance – Fasting blood glucose level ≥110 mg/dL
• High blood pressure – ≥130/85 mm Hg
• Elevated triglyceride levels – >250 mg/dL
• HDL cholesterol level – <40 mg/dL for men; <50 mg/dL for women
• Abdominal obesity – Waist: >102 cm (40 inches) for men; >88 cm (35 inches) for women¹⁵

In addition, nonalcoholic fatty liver is associated with type 2 diabetes mellitus and high blood pressure.^16-17 Certain medications can also contribute toward the development of NAFL. This includes amiodarone, antiviral drugs (nucleoside analogues), aspirin (rarely as part of Reye’s syndrome in children), corticosteroids, methotrexate, tamoxifen and tetracycline.¹⁸

Diagnosis

Due to the fact that nonalcoholic fatty liver is often asymptomatic, it tends to be found incidentally while testing for an unrelated problem, such as may be the case when testing for elevated aminotransferase levels (liver enzyme) as part of a routine checkup or when monitoring is performed for possible side effects of drugs. In any case, the following tests may be used to confirm the diagnosis:¹⁹

• Blood Tests – Measurements of global liver function and inflammatory activity should be performed, along with additional blood tests to exclude viral hepatitis (liver enzyme levels are normal in a large percentage of NAFL):
  • Serum aminotransferase – Mild to moderate elevation is common (mean range, 100-200 IU/L).
  • AST to ALT ratio – Generally less than 1, but increases as fibrosis advances.
  • Serum alkaline phosphatase and g-glutamyl transpeptidase – May be mildly abnormal.
  • Serum levels of fasting cholesterol and triglycerides, as well as fasting glucose and insulin, should be determined – More than 80 percent of patients with NAFL have some components of the metabolic syndrome.
• Liver Ultrasound – To look for irregularities in the shape and consistency of the liver and for problems of the biliary tract, such as gallstones.
• Computed Tomography (CT) – To provide a detailed view of the liver.
• Liver Biopsy – May be needed in some cases.

Conventional Treatment

According to the Mayo Clinic, there is no proven, conventional, medical treatment for NAFL,²⁰ although they suggest that excess fat in the liver can often be reduced through:

• Gradual and sustained weight loss
• Exercise and healthy dietary changes
• Tight control of blood glucose levels (for diabetics)
• Bariatric surgery to alter the digestive system and promote weight loss (in some obese patients)
  In addition, if the liver has been severely damaged by NAFL, a liver transplant may be a necessary option.²¹

Integrative Approaches

As previously stated, the liver plays a primary role in the detoxification of exogenous and endogenous biochemicals. This occurs via detoxification pathways in the liver called “phase 1” and “phase 2,”^22-24 which ultimately attaches or conjugates a water-soluble substance onto the toxin to facilitate its excretion via the bile or the urine.^25-26 Given that some of these toxins may play a role in the etiology of NAFL²⁷, this underscores the importance of taking an integrative approach to support and promote liver detoxification mechanisms with the use of key nutraceuticals found in Detox Complex, AL-CoFactors™, Gallbladder Formula and HepatoGen™.

Certain amino acids are used in phase 2 as conjugating agents. These amino acids include glycine, taurine and glutamine.²⁸ Clinically, supplementation with these amino acids has shown great benefit for patients with toxic overload, especially when body cleansing was undertaken contemporaneously.²⁹ Likewise, methyl groups also act as conjugating agents in phase 2.³⁰ MSM or methylsulfonylmethane³¹ and Trimethylglycine or betaine³² are donors of methyl groups, and may be useful as such in biochemical reactions in the liver. In addition, animal research has demonstrated that trimethylglycine is capable of stopping the development of non-alcoholic fatty livers, as well as improving parameters of existing NAFL.³³

Another phase 2 pathway is the glucuronidation pathway. In this pathway, glucuronic acid is attached to certain toxins as well as hormones such as estrogen to facilitate their removal by excreting them via bile into the intestinal tract. The problem is that beta-glucuronidase, a bacterial enzyme found in the intestines, can break the bond that attaches the glucuronic acid to the toxin. Calcium D-glucarate, the calcium salt of D-glucaric acid, a natural substance found in many fruits and vegetables, has been shown to inhibit beta-glucuronidase^34-35, thereby doing much to protect the action of the glucuronidation pathway.

The glutathione conjugation pathway is a major phase 2 pathway through which toxic molecules pass. N-acetyl cysteine (NAC) is the precursor to glutathione³⁶, it stimulates glutathione synthesis and promotes liver detoxification; as well as acting as a powerful scavenger of free radicals.³⁷ In addition, the metabolic antioxidant R-lipoic or alpha lipoic acid has been found to increase glutathione synthesis³⁸ by increasing cellular uptake of cysteine which is required for glutathione synthesis.³⁹ Equally significant is that in animal research, NAC was able to help stop many aspects of the progression of non-alcoholic fatty livers.⁴⁰ Furthermore, lipoic acid was before also able to keep the livers completely healthy.⁴¹

Furthermore, research shows that silymarin from Milk Thistle protects against glutathione depletion⁴², and increases liver glutathione status⁴³, thereby supporting detoxification by the liver.⁴⁴ In addition, Milk Thistle stimulates the production of bile⁴⁵, which is significant since bile acts as a vehicle to excrete toxins into the colon once they have completed phase 2 conjugation. Also, Milk Thistle has been said to have clinical application for fatty liver. This has been demonstrated in a pilot study when Milk Thistle, combined with vitamin E and phosholipids, improved parameters of fatty liver.⁴⁶ Likewise, a number of in vitro studies have investigated Milk Thistle’s role in supporting the health of the liver. For example, in one of these studies, silymarin protected liver cells from cell death induced by saturated fatty acids.⁴⁷

Artichoke has a similar effect to Milk Thistle with regard to stimulating bile flow, which has been demonstrated in several studies.⁴⁸ By this mechanism, Artichoke can also help in the excretion of toxins.

Conclusion

Non-alcoholic fatty liver is a prevalent but under-recognized threat to wellness. Supporting the health of the liver through using key botanicals, amino acids and natural detoxifying agents can ensure this organ continues to fulfill its essential role.

References

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