Final answer:
Ethanol is metabolized in the liver to acetyl CoA, which is used for lipid synthesis. Excess ethanol leads to more acetyl CoA than needed for energy, resulting in increased fatty acid production. This excessive lipid synthesis can cause an abnormal accumulation of fats in the liver, also known as fatty liver disease.
Step-by-step explanation:
Ethanol consumption leads to the accumulation of fats in the liver, which is a condition known as fatty liver. When ethanol is metabolized, it is broken down into acetate, which is further converted to acetyl CoA in liver cells. This acetyl CoA is pivotal in lipogenesis, the process that synthesizes fatty acids and cholesterol.
Lipogenesis occurs when the body has an excess of carbohydrates and energy in the form of ATP, leading to an abundance of acetyl CoA. This, in turn, facilitates the production of lipids, including triglycerides and cholesterol, within hepatocytes (liver cells). When consumption of ethanol is chronic or excessive, it introduces more acetyl CoA into the liver than can be used for energy, prompting an increase in lipid synthesis.
Additionally, ethanol metabolism can raise plasma free fatty acids, encouraging the liver to secrete more very-low-density lipoprotein (VLDL), which carries triglycerides and cholesterol into the bloodstream. These metabolic changes can lead to an abnormal rise in the lipid content within the liver, surpassing the normal 5% threshold to potentially 25-30%, resulting in fatty liver disease.