Which Deficiency Causes Lung Cancer? The Role of Nutrition and Genetics

December 15, 2025 •

4 min read

According to the World Health Organization, lung cancer remains the leading cause of cancer-related death globally, and while smoking is the primary risk factor, other causes are also being investigated. A growing body of research suggests that certain genetic conditions and specific nutritional deficiencies can increase a person's risk of developing this deadly disease, highlighting the complex relationship between diet, genetics, and lung health.

Quick Summary

The link between specific deficiencies and lung cancer is multifaceted, involving genetics like AAT deficiency and nutritional factors. While vitamin D and selenium deficiencies are associated with higher risk, other micronutrients like B vitamins require careful consideration, particularly with high-dose supplementation.

Key Points

Alpha-1 Antitrypsin Deficiency (AATD): A genetic condition, not a nutritional one, that significantly increases the risk of lung cancer, especially in smokers.
Vitamin D Deficiency: Strongly correlated with an increased risk of lung cancer and poorer survival rates, likely due to its role in regulating cell growth and immunity.
High-Dose B Vitamin Supplementation: Linked to an increased risk of lung cancer, especially in male smokers. Excessive intake, often from supplements, appears problematic rather than dietary intake.
Selenium Levels: Low selenium status is associated with higher cancer risk in populations with low baseline levels. Selenium functions as an antioxidant, but its effect is complex and dose-dependent.
Complex Interactions: The risk associated with genetic and nutritional deficiencies is often amplified by environmental and lifestyle factors, with tobacco smoke being the most significant modifying factor.
Nutrient-Rich Diet: A varied diet rich in fruits, vegetables, and other whole foods is the most recommended approach for obtaining protective micronutrients like antioxidants.

No Single Deficiency Directly Causes Lung Cancer

It's important to clarify that no single nutritional deficiency is a direct or sole cause of lung cancer. Instead, researchers have identified several nutritional and genetic factors that may increase risk, especially when combined with major risk factors like tobacco smoke. The development of lung cancer is a complex process influenced by a combination of genetic predispositions, environmental exposures, and overall physiological health.

The Role of Alpha-1 Antitrypsin (AAT) Deficiency

Unlike nutritional deficiencies, Alpha-1 Antitrypsin Deficiency (AATD) is a rare genetic disorder proven to be a specific risk factor for lung disease, including an increased risk of lung cancer. AAT is a protein that protects the lungs from damage caused by inflammation. A genetic deficiency in this protein can lead to a protease-antiprotease imbalance, leaving lung tissue vulnerable to damage and increasing the risk of both emphysema and lung cancer, particularly in smokers or former smokers. Research has explored the link, suggesting that AAT deficiency may increase the risk of developing adenocarcinoma and squamous cell carcinoma.

Vitamins and Their Complex Association with Lung Cancer

Several vitamins and micronutrients have been studied for their potential link to lung cancer risk. While some, like vitamin D, show a protective effect, others, such as high-dose beta-carotene and certain B vitamins, have demonstrated unexpected risks under specific conditions.

Vitamin D Deficiency

Numerous studies indicate a significant association between low circulating levels of vitamin D and an increased risk of lung cancer incidence and mortality.

Inhibits cancer cell growth: Vitamin D can bind to the vitamin D receptor (VDR) to inhibit cancer cell proliferation and promote apoptosis (programmed cell death).
Supports immune function: It also helps regulate immune function, which is critical in fighting against cancer cells.
Linked to smokers: Tobacco smoke is known to lower vitamin D levels, and lung cancer patients often have low concentrations of this vitamin. Correcting a vitamin D deficiency may hold therapeutic potential.

The Vitamin B Paradox

For some B vitamins, the story is more complex. While B vitamins are crucial for cellular metabolism, high-dose, long-term supplementation has been linked to an increased risk of lung cancer, particularly in men who smoke.

Vitamin B6 and B12: One cohort study found that male smokers taking high-dose B6 and B12 supplements for over a decade had a significantly higher risk of lung cancer than non-users.
Beta-carotene: Similarly, early studies on beta-carotene supplementation in smokers were halted due to an increased incidence of lung cancer in the supplement group.

Selenium's Role

Selenium is a micronutrient with antioxidant properties that play a significant role in protecting against oxidative stress, a process that can lead to DNA damage and cancer.

Protective in low-level populations: Studies, including in Poland where low soil selenium is common, have shown that low selenium levels are associated with a higher incidence of lung cancer.
Complex role: The link is not straightforward, as the benefits of selenium are most apparent in populations with existing deficiencies, and high doses can be toxic.

Diet, Minerals, and Lung Cancer Risk

Beyond specific vitamins, broader dietary patterns and mineral intake can influence lung cancer risk.

Antioxidant-Rich Diets

Diets rich in fruits, vegetables, and other antioxidant-rich foods are linked to a reduced risk of lung cancer. These foods contain a variety of protective compounds, including various vitamins, minerals, and polyphenols.

Iron and Zinc Intake

A study from the Rotterdam Study found that higher dietary intake of both zinc and iron was associated with a reduced risk of lung cancer. The inverse association was particularly significant for heme iron in men.

Comparison of Key Nutritional Factors and Lung Cancer Risk


Factor	Role in Lung Health	Associated Risk/Benefit	Key Caveat
Vitamin D	Regulates immune function and cell growth.	Lower deficiency linked to reduced lung cancer risk and better survival.	Maintaining adequate, not excessive, levels is key.
Selenium	Antioxidant that protects against oxidative stress.	Reduced lung cancer risk in populations with low baseline levels.	Risk-benefit is dose-dependent; high doses can be toxic.
Vitamin B6 & B12	Crucial for metabolism and DNA function.	High-dose supplementation linked to increased risk, especially in male smokers.	High intake should be from food, with caution regarding supplements.
Alpha-1 Antitrypsin (AAT)	Genetic protein protects lung tissue.	Deficiency is a specific genetic risk factor for lung cancer.	Not a nutritional deficiency, but a hereditary condition requiring specialized management.

The Broader Context of Lung Cancer Risk

Ultimately, nutritional deficiencies and genetic predispositions are not isolated factors but interact with other powerful influences, such as smoking, which remains the single greatest risk factor. For individuals with a genetic susceptibility like AAT deficiency, exposure to tobacco smoke significantly amplifies their risk. Environmental factors, such as air pollution and radon exposure, also contribute to the overall risk profile. Therefore, while addressing nutritional status is beneficial, it must be considered within the larger context of a patient's genetics and lifestyle to fully understand and mitigate lung cancer risk.

Conclusion: A Multi-Pronged Approach to Risk

There is no single deficiency that acts as a sole cause of lung cancer. Instead, the disease is influenced by a complex web of factors. Alpha-1 Antitrypsin Deficiency is a direct genetic risk factor, while deficiencies in micronutrients like vitamin D and selenium are associated with increased risk, particularly in specific populations and with certain lifestyles. Conversely, megadoses of some supplements like specific B vitamins may be detrimental. A comprehensive strategy for lung cancer prevention and risk management involves maintaining a balanced, nutrient-rich diet, avoiding tobacco smoke, and understanding one's personal genetic risk factors. These measures work together to support overall lung health and mitigate cancer risk.

Frequently Asked Questions

While not a direct cause, low levels of vitamin D are strongly associated with a higher risk of developing lung cancer and can negatively affect survival outcomes. Maintaining adequate vitamin D levels through diet, sunlight, or moderate supplementation is beneficial.

High-dose supplementation with certain B vitamins, particularly B6 and B12, has been linked to an increased risk of lung cancer, especially in male smokers. Most people can get sufficient B vitamins from a balanced diet, and high-dose supplements should be used with caution and under medical advice.

Some evidence suggests that low baseline selenium levels are associated with a higher risk of certain cancers, including lung cancer, in deficient populations. Selenium's antioxidant properties are thought to be protective, but excessive intake can be toxic.

No, Alpha-1 Antitrypsin Deficiency (AATD) is a rare inherited genetic disorder, not a nutritional one. It causes a protein deficiency that can lead to lung and liver diseases and increases the risk of lung cancer.

No, diet alone cannot prevent lung cancer, but a nutrient-rich diet high in fruits and vegetables can support overall health and may lower risk when combined with other preventive measures. Avoiding major risk factors like smoking is far more impactful.

High-dose antioxidant supplements, such as beta-carotene, have not been proven to prevent lung cancer and have, in some studies involving smokers, been linked to an increased risk. It is generally safer and more effective to get antioxidants from a varied diet.

Genetic factors, such as inherited mutations and specific gene variations, can increase susceptibility to lung cancer, often interacting with environmental and lifestyle factors like smoking or nutrient deficiencies to determine overall risk. AAT deficiency is a clear example of this genetic link.