The liver is one of the body's most remarkable organs — uniquely capable of regenerating up to 75% of its mass after damage. It performs over 500 distinct functions, from filtering toxins and producing bile to synthesising proteins and regulating blood sugar. But this regenerative capacity has limits.
Each unit of alcohol takes the liver approximately one hour to process. When alcohol arrives faster than the liver can metabolise it, the excess circulates in the blood — causing the familiar effects of intoxication. Over time, regular excess intake leads to a cycle of damage and attempted repair that, in chronic cases, produces scarring (fibrosis).
Liver fibrosis is graded F0–F4. F0 means no scarring; F4 is cirrhosis, which is largely irreversible. The progression from F0 to F4 typically takes 15–20 years of heavy drinking — but early stages (F1–F2) can be reversed if alcohol intake is reduced sufficiently.
NAFLD is now the most common liver condition in the UK, affecting around 1 in 3 people — most without any symptoms. It's driven by poor diet, obesity and sedentary lifestyle, and can progress to the same fibrosis pathway as alcohol-related liver disease. Unlike alcohol damage, NAFLD can be reversed with diet and exercise in its early stages.