The Claim

Persistently poor sleep quality, defined as a Pittsburgh Sleep Quality Index score of 6 or higher over two assessments, is associated with a 13% higher risk of developing incident non-alcoholic fatty liver disease in adults, independent of sleep duration and body mass index.

Source: Decrease in Sleep Duration and Poor Sleep Quality over Time Is Associated with an Increased Risk of Incident Non-Alcoholic Fatty Liver Disease

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
67score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Correlation
1 study reviewed
In plain English

Adults with consistently poor sleep quality, as measured by a standardized sleep questionnaire, have a 13% higher incidence of non-alcoholic fatty liver disease compared to those with better sleep quality, even when accounting for how long they sleep and their body weight.

See the scientific wording

Persistently poor sleep quality, defined as a Pittsburgh Sleep Quality Index score of 6 or higher over two assessments, is associated with a 13% higher risk of developing incident non-alcoholic fatty liver disease in adults, independent of sleep duration and body mass index, indicating that sleep quality may be an independent contributor to liver disease risk.

Why this might work

When sleep is consistently poor, the body's stress system stays turned on, releasing too much cortisol and adrenaline. This makes the liver resistant to insulin, causes fat to build up inside liver cells, and triggers inflammation that damages the liver over time, leading to fatty liver disease.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Decrease in Sleep Duration and Poor Sleep Quality over Time Is Associated with an Increased Risk of Incident Non-Alcoholic Fatty Liver Disease

    People who consistently have bad sleep—like tossing and turning or not feeling rested—are 13% more likely to develop fatty liver disease, even if they sleep the right number of hours and aren’t overweight. This study shows sleep quality itself matters for liver health.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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