How the Liver Changes with Age
Despite its remarkable regenerative abilities, the liver is not immune to the aging process. As we get older, several physiological and structural changes take place that can compromise its function over time. These changes affect both the liver's macroscopic structure and its cellular components.
- Decreased Size and Blood Flow: Studies have shown that the liver's volume can decrease by 20–40% in older adults. This is accompanied by a significant reduction in hepatic blood flow, which can decrease by approximately 35% in individuals over 65 compared to those under 40. Less blood flow means less efficiency in processing substances.
- Cellular and Structural Alterations: On a microscopic level, liver cells (hepatocytes) can become larger and accumulate lipofuscin, an 'age pigment,' due to impaired cellular waste removal processes like autophagy. The number and function of mitochondria within the cells also decline, impacting energy production.
- Changes to Sinusoidal Endothelial Cells: The liver's microvasculature, particularly the liver sinusoidal endothelial cells (LSECs), undergoes a process called 'pseudocapillarization'. This involves a reduction in the tiny pores (fenestrations) that facilitate exchange between the blood and liver cells. This change can impair the liver's ability to take up lipids and other substances from the blood effectively.
- Reduced Regenerative Capacity: The liver's famed ability to regrow and repair itself after injury diminishes significantly with age. This delayed healing makes older livers more vulnerable to damage from infections, toxins, and alcohol.
Age-Related Risks and Liver Diseases
The physiological changes of an aging liver increase the risk and progression of several liver diseases. While the liver is resilient, it becomes more vulnerable to various stressors over time.
Increased Risk of Fatty Liver Disease
Non-alcoholic fatty liver disease (NAFLD), now often referred to as metabolic dysfunction-associated steatotic liver disease (MASLD), is strongly associated with aging. As older adults are more prone to cardiometabolic risk factors like obesity, diabetes, and dyslipidemia, MASLD prevalence increases with age. An aging liver is less efficient at metabolizing fats, leading to lipid accumulation and a higher likelihood of MASLD progressing to inflammation, fibrosis, or cirrhosis.
Impact of Alcohol-Related Liver Disease
Excessive alcohol consumption can have a more severe impact on an older liver. With reduced metabolism and a diminished hepatic reserve, older adults are more vulnerable to alcohol toxicity. In fact, elderly patients with alcohol-related liver disease often present with more advanced stages than younger individuals. Social isolation or bereavement can also contribute to increased alcohol use disorder in seniors.
Polypharmacy and Drug-Induced Liver Injury (DILI)
Seniors often take multiple medications for chronic conditions, a practice known as polypharmacy. Since the aging liver metabolizes drugs more slowly, the risk of drug buildup and drug-induced liver injury (DILI) increases. Medications that are normally safe in younger adults may require lower dosages in seniors to prevent side effects. This is a particular concern with many commonly prescribed drugs and over-the-counter supplements.
Comparison: Young vs. Aged Liver
To illustrate the differences, here is a comparison of a healthy young liver and a typical aged liver.
| Feature | Young Liver | Aged Liver |
|---|---|---|
| Size & Volume | Standard volume and weight. | Can decrease by 20–40%. |
| Blood Flow | Efficient and robust hepatic blood flow. | Reduced blood flow, potentially by 35% or more. |
| Regeneration | Remarkable capacity for repair and regeneration after injury. | Significantly reduced regenerative ability and slower repair. |
| Drug Metabolism | More efficient metabolism of medications and toxins. | Slower metabolism, increased risk of drug-related toxicity. |
| Fat Accumulation | Lower risk of fat buildup in hepatocytes. | Increased tendency for fat accumulation, raising MASLD risk. |
| Stress Tolerance | Better able to withstand stress and toxic substances. | Reduced tolerance, making it more vulnerable to damage. |
Steps to Support Your Aging Liver
While some age-related changes are inevitable, lifestyle choices can significantly impact liver health. Proactive steps can help preserve liver function and reduce the risk of disease.
- Maintain a Healthy Weight: Obesity is a major risk factor for fatty liver disease, which is more common with age. A balanced diet and regular exercise can help control weight and reduce liver fat.
- Limit Alcohol Consumption: Moderating or avoiding alcohol is crucial, as the aging liver is less resilient to its toxic effects.
- Manage Medications Carefully: Discuss all prescription, over-the-counter, and herbal supplements with your doctor. Regular blood work and adjustments to dosages may be necessary to prevent DILI.
- Stay Hydrated: Drinking plenty of water supports kidney and liver function.
- Eat a Balanced Diet: Focus on whole foods rich in fiber, lean protein, and healthy fats while limiting processed foods, sugar, and saturated fats.
- Regular Exercise: Physical activity improves circulation, aids digestion, and can help reduce liver fat.
- Get Vaccinated: Vaccinations for hepatitis A and B can protect the liver from viral infections.
Conclusion
The liver does indeed get weaker with age, undergoing predictable structural and functional changes. While this is a normal part of aging, it increases the liver's vulnerability to diseases like MASLD, alcoholic liver disease, and drug-induced injury. However, by adopting a proactive approach to health—including maintaining a healthy weight, limiting alcohol, and carefully managing medications—it is possible to support your liver and maintain its function well into your later years. Regular check-ups are also vital for monitoring liver health and addressing any potential issues early.
To learn more about the scientific basis of liver aging and disease, see this detailed review: Liver, ageing and disease.
