Nonalcoholic fatty liver disease (NAFLD) is subdivided into nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH). In the United States, prevalence of NAFLD is 10% to 46% of the population. Worldwide prevalence is 6% to 35% (median 20%). There is a need to increase understanding of liver disease and its many causes, which will help to improve patient outcomes and reduce the stigma many patients experience. This article discusses epidemiology, etiologies, suspected pathogenesis, and risk factors, along with conventional and naturopathic therapeutic treatment options.
Nonalcoholic Fatty Liver Disease
In clinical reality, nonalcoholic fatty liver disease typically comes to the attention of the healthcare practitioner because laboratory testing reveals elevated liver aminotransferases.
- Weight loss for patients who are overweight or obese;
- Hepatitis A and B vaccinations, except in those with serologic evidence of immunity21;
- Treatment of risk factors for cardiovascular disease; and
- Abstention from alcohol.
- Tocotrienols: 200 mg twice daily with food.34 Gamma-tocotrienol, but not alpha-tocopherol, attenuates triglycerides accumulation by regulating fatty acid synthase and carnitine palmitoyltransferase enzymes, leading to a reduction of hepatic inflammation and endoplasmic reticulum stress.35
- N-acetyl-cysteine (NAC): 600 mg twice daily, best taken on an empty stomach.36 NAC blocks the propagation of lipid peroxidation.37
- Omega 3 essential fatty acids: 2 g to 4 g daily.38 Omega 3 polyunsaturated fatty acids are known to downregulate sterol regulatory element binding protein 1c and upregulate peroxisome proliferator activated receptor α, which would favor fatty acid oxidation and reduce steatosis.39
- Silybum marianum (milk thistle): 280 mg to 360 mg daily.40 Phytosomes provide the greatest bioavailability.41 Silymarin interferes with leukotriene formation in Kupffer cell cultures, thus inhibiting hepatic stellate cell activation.42
- L-carnitine: 1 g twice daily.43 L-carnitine plays a critical role in fatty acid oxidation of energy regulation. It serves as a carrier to facilitate the transport of long-chain fatty acids through the mitochondrial membrane and to undertake free fatty acid b-oxidation.44
- Choline: 250 mg to 1,000 mg daily.45 The precise mechanism of choline is unknown, except for its methyl donor properties and the observation that those with genetic polymorphisms involved in choline biosynthesis are associated with an increased risk of developing fatty liver.46
- Betaine: 20 g daily (1-6 g/d may beneficial if used in conjunction with other therapies).47 Betaine, when used in rats with alcohol-induced steatohepatitis, led to an increase in S-adenosyl-l-methionine, which in turn led to a reduction in hepatic steatosis.47
- Vitamin E (as RRR-α-tocopherol): 400 IU twice daily with food.48 Although well studied, I don’t utilize this treatment by itself due to increased risk for adverse cardiovascular events49 and gamma-tocopherol depletion50 at this dose. Mixed tocopherols have also shown efficacy in NAFL.35 Vitamin E is an effective defense mechanism against lipid peroxidation.51 Lipid peroxidation is increased in NAFLD and can promote inflammation and tissue damage.52
Given the relatively high US prevalence of non-alcoholic fatty liver disease, along with its strong correlation in conditions such as metabolic syndrome, types I and II diabetes, obesity and dyslipidemia, evidence-based naturopathic strategies and interventions lay the framework for these treatments to take center stage.
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