Does nicotine affect your liver and kidneys?

September 28, 2025 •

4 min read

According to the Centers for Disease Control and Prevention, smoking contributes to preventable illness and mortality in the United States. The liver and kidneys are particularly vulnerable, and growing evidence confirms that nicotine does affect your liver and kidneys, contributing to inflammation, oxidative stress, and tissue damage.

Quick Summary

Yes, nicotine negatively impacts the liver and kidneys by causing inflammation, oxidative stress, and reduced blood flow, contributing to the development and progression of chronic diseases like liver fibrosis, fatty liver disease, and chronic kidney disease.

Key Points

Liver Damage: Chronic nicotine use causes oxidative stress and inflammation in the liver, which can lead to fat accumulation, fibrosis, and scarring (cirrhosis).
Kidney Damage: Nicotine is toxic to kidney cells (podocytes) and constricts blood vessels, reducing blood flow and impairing filtering function.
Risk of Disease Progression: Nicotine accelerates the progression of chronic conditions like nonalcoholic fatty liver disease (NAFLD) and diabetic kidney disease.
Increased Cancer Risk: Long-term nicotine exposure increases the risk of liver and kidney cancers due to toxic and oncogenic effects.
Systemic Effects: The damage is caused by both direct cellular toxicity and indirect effects, such as nicotine-induced vasoconstriction and systemic inflammation.
Quitting Improves Health: The negative effects are reversible, and quitting nicotine can improve liver and kidney health and slow the progression of related diseases.

The Liver's Role in Nicotine Metabolism

The liver is the body's primary detoxification center, and it plays a major role in metabolizing nicotine. When nicotine enters the body, the liver works to break it down, producing a number of metabolites, most notably cotinine. This process involves enzymes from the cytochrome P450 family, particularly CYP2A6. While this is a normal metabolic function, chronic exposure to nicotine forces the liver into a constant state of high activity, which can lead to significant stress and damage over time.

Mechanisms of Liver Damage

Chronic nicotine consumption can cause liver damage through several key mechanisms:

Oxidative Stress: Nicotine metabolism generates reactive oxygen species (ROS), which can overwhelm the body's antioxidant defenses, leading to cellular damage. This stress activates cells that cause fibrosis.
Inflammation: Nicotine increases pro-inflammatory cytokines, which contribute to liver cell injury. This chronic inflammation is a precursor to many liver diseases.
Fibrosis and Scarring: Oxidative stress and inflammation activate stellate cells, which produce excessive fibrous tissue, leading to liver scarring, or fibrosis. In its severe form, fibrosis progresses to cirrhosis, a permanent condition.
Fat Accumulation: Nicotine can disrupt lipid metabolism, causing fat to accumulate in the liver and potentially leading to nonalcoholic fatty liver disease (NAFLD).

Liver Disease and Nicotine Use

Research has linked smoking, and by extension nicotine, to several liver conditions:

NAFLD and NASH: Studies show that smoking is an independent risk factor for NAFLD, with a dose-response relationship between pack-years and the progression of fibrosis. Nicotine exposure promotes lipid accumulation and inflammation, particularly in cases of nonalcoholic steatohepatitis (NASH).
Liver Cancer: Nicotine and other tobacco compounds are carcinogenic, increasing the risk of hepatocellular carcinoma (HCC). Smoking is also linked to the progression of liver cancer in individuals with underlying conditions like hepatitis B or C.
Primary Biliary Cholangitis (PBC): Studies have found a dose-dependent relationship between smoking intensity and the likelihood of advanced fibrosis in patients with PBC.
Post-Transplant Complications: For liver transplant recipients, smoking can increase the risk of vascular complications, malignancy, and mortality.

Nicotine's Effects on Kidney Health

The kidneys are also responsible for filtering and excreting nicotine and its metabolites. Similar to the liver, this process is not without consequences, and chronic exposure can lead to significant renal damage.

Mechanisms of Kidney Damage

Nicotine impairs kidney function through various mechanisms:

Vasoconstriction: Nicotine causes blood vessels to narrow, reducing blood flow to the kidneys. This can impair the kidneys' ability to filter waste effectively and contributes to hypertension, a leading cause of kidney damage.
Cellular Toxicity: Nicotine is directly toxic to kidney cells, particularly podocytes, which are crucial for the kidney's filtering function. This toxicity leads to cellular injury and death.
Oxidative Stress and Inflammation: Nicotine induces oxidative stress in kidney tissue, contributing to cellular injury. It also promotes inflammation by upregulating inflammatory enzymes.
Progression of Existing Kidney Disease: For individuals with pre-existing conditions like diabetic kidney disease or chronic kidney disease (CKD), nicotine accelerates disease progression and increases the risk of renal failure.
Proteinuria: Nicotine is associated with an increase in protein in the urine, an early indicator of kidney damage.

Renal Health and Nicotine Use

Chronic nicotine use, whether through cigarettes or e-cigarettes, is a known risk factor for kidney problems. For individuals with diabetes, nicotine significantly increases the risk of renal failure. Quitting nicotine can help slow the progression of kidney damage and improve overall renal health.

A Comparison of Nicotine's Effects on Liver and Kidneys


Feature	Liver Effects	Kidney Effects
Primary Mechanism	Metabolizes nicotine, leading to oxidative stress and inflammation.	Filters nicotine, with damage resulting from vasoconstriction and cellular toxicity.
Cellular Impact	Damages hepatocytes and activates stellate cells, leading to fibrosis.	Is toxic to podocytes and other renal cells, contributing to cellular death.
Major Conditions	NAFLD, fibrosis, cirrhosis, and liver cancer risk are increased.	CKD, renal failure (especially with diabetes), proteinuria, and kidney cancer risk are increased.
Vascular Impact	Reduces hepatic blood flow by increasing endothelin-1, a vasoconstrictor.	Reduces renal blood flow by narrowing blood vessels.
Metabolic Impact	Disrupts lipid metabolism, promoting fat accumulation.	Contributes to hypertension, affecting overall metabolic and renal health.
Effect on Existing Conditions	Worsens conditions like NAFLD, hepatitis, and increases risk for post-transplant complications.	Accelerates progression of diabetic kidney disease and CKD.

Conclusion: The Combined Impact of Nicotine on Organ Health

The evidence clearly shows that nicotine, the addictive agent in tobacco and e-cigarettes, negatively affects both the liver and the kidneys. Through chronic oxidative stress, inflammation, and reduced blood flow, nicotine directly contributes to the damage of these vital organs. For the liver, this can lead to conditions ranging from fatty liver disease to severe cirrhosis and cancer, while for the kidneys, it increases the risk of chronic kidney disease and renal failure. The negative effects are particularly pronounced in individuals with pre-existing health issues like diabetes. Quitting nicotine use is one of the most effective ways to mitigate these risks and support the long-term health of your liver and kidneys.

If you or someone you know is struggling with nicotine addiction, resources are available to help. For guidance and support, visit the CDC website to find help quitting.

Frequently Asked Questions

Yes, vaping can affect your liver and kidneys because most e-cigarette aerosols contain nicotine, which is the primary agent linked to liver and kidney damage. Studies show that nicotine, whether from conventional or electronic cigarettes, causes oxidative stress and inflammation that harm these organs.

Yes, the damaging effects of nicotine on the liver can occur regardless of the delivery method. Nicotine, when metabolized by the liver, can cause oxidative stress and potentially contribute to conditions like fatty liver disease, even in non-smokers who use nicotine replacement products or e-cigarettes.

Nicotine primarily damages the kidneys through two main mechanisms: vasoconstriction and direct cellular toxicity. It narrows the blood vessels, which reduces blood flow to the kidneys, and is also directly toxic to the filtering cells, particularly podocytes.

Some early stage liver damage from smoking may be reversible. The liver has regenerative capabilities, and quitting nicotine use can decrease inflammation and stop the influx of toxins, potentially allowing the liver to recover. However, advanced scarring (cirrhosis) is permanent.

Yes, passive smoking, or exposure to secondhand smoke, has been linked to liver damage. The toxic chemicals can still be absorbed into the bloodstream and processed by the liver, contributing to inflammation and oxidative stress.

Yes, nicotine is especially harmful to diabetic patients. For those with diabetic kidney disease, nicotine significantly increases the risk of renal failure and accelerates disease progression.

While nicotine replacement therapies (NRTs) like patches and gum avoid the thousands of other toxins in tobacco smoke, they still deliver nicotine. Nicotine itself causes harm through oxidative stress and vasoconstriction. The risk is reduced compared to smoking, but chronic use still poses a risk to liver and kidney function.