Study under review: Systematic review and meta-analysis of controlled intervention studies on the effectiveness of long-chain omega-3 fatty acids in patients with nonalcoholic fatty liver disease
Non-alcoholic fatty liver disease (NAFLD) is a condition in which excessive fat (more than 5% of liver weight) accumulates in the liver due to causes unrelated to alcohol. Depending on the method of diagnosis, the prevalence of NAFLD in the U.S. is 21-24%. The primary risk factors for NAFLD are obesity, type 2 diabetes, dyslipidemia, and the metabolic syndrome.
Although NAFLD is a condition associated with adults, there has been a rise in the presence of NAFLD in children over the last several decades. The average prevalence is about 8%, with rates as high as 38% in some groups of children. Despite the prevalence of the disease in adults, and the burgeoning issue in children, there are no therapeutic agents currently approved for managing NAFLD. This is a problem, since NAFLD can ultimately progress to non-alcoholic steatohepatitis (NASH - inflamed fatty liver not due to alcohol).
Long-chain omega-3 fatty acids, specifically EPA and DHA, have been investigated as potential therapeutics for NAFLD because they have been shown to alter expression of genes related to fatty acid metabolism in the liver. Specifically, they have been shown to increase expression of genes related to fatty acid oxidation and decrease expression of genes related to fatty acid synthesis.
There have been a myriad of clinical trials investigating the effect of omega-3 supplementation in both adults and children with NAFLD. Some of these trials have been previously examined in a systematic review and meta-analysis. However, the previous study did not include children and there has been additional research since its publication in 2012. Therefore, the purpose of this study was to perform a contemporary systematic review and meta-analysis on the effect of omega-3 supplementation in adults and children with NAFLD on liver-related outcomes and metabolic risk factors.
NAFLD affects roughly a quarter of the adult population in the U.S., while rates in children are growing at an alarming rate. Omega-3 fatty acids have been shown to directly modulate genes related to fatty acid metabolism in the liver. The present study is a systematic review and meta-analysis examining the effect of omega-3 supplementation in adults and children with NAFLD on liver-related outcomes and metabolic risk factors.
Other Articles in Issue #47 (September 2018)
Betaine: Can it improve body composition and performance in women?
This is the first study to look at betaine's effects on body composition and performance in women who have just started lifting.
Smackdown: Whole grains versus fruits and vegetables effects on inflammation and the gut microbiome
Overweight and obesity can be accompanied by subclinical inflammation, which may be tied in part to the gut microbiome. This study aimed to find out how increasing fruit and veggie or whole grain intake affects these.
Which oils or fats have the best effect on cholesterol?
Different oils and fats can have very different effects on blood lipids. This network meta-analysis explored exactly how different the effects are.
Mini: What’s healthy about chocolate?
We summarize which health claims about chocolate have some evidence to back them up according to a recent umbrella review on the matter.
Cheese reloaded: enter the matrix
Context matters when it comes to macronutrients’ impact on lipid levels.
Gut bugs as bone drugs
What effect can probiotic supplementation have on bone density? This study aimed to find out
Mini: The sports supplements with the highest amount of evidence according to the ISSN
We summarize which supplements have the best evidence base for muscle building and performance enhancement according to the ISSN’s recently updated sports nutrition review.