Did you know that the “sunshine vitamin” might play a role in lung health and cancer prevention? You might think of vitamin D as essential for strong bones, but recent research suggests it may also be linked to lung cancer.

Several MyLungCancerTeam members have mentioned that vitamin D plays a part in their treatment plan. One member wrote, “My husband’s calcium dipped a bit, so I was notified today to go get him some over-the-counter calcium and vitamin D to help enhance his infusion.”

Let’s explore the possible connection between vitamin D and lung cancer and what it could mean for your health journey.

What Is Vitamin D?

Vitamin D is a nutrient that your body needs to make your muscles move, help your nerves send signals, and allow your immune system to fight off bacteria and viruses that can make you sick. Another role of vitamin D is that it helps the body absorb calcium to have strong and healthy bones.

There are two main types of vitamin D — vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Both types are produced naturally from the sun’s ultraviolet rays. Additionally, vitamin D2 is also produced in plants, mushrooms, and yeast while vitamin D3 is produced in animals.

Your body also breaks vitamin D down into its active form, calcitriol (1,25-dihydroxyvitamin D) through vitamin D receptors. This active form influences cells involved in your immune system and is also available as a daily or weekly supplement.

Sources of Vitamin D

Eating nutritious food can ensure your body is getting the right balance of vitamins, which is especially important for people who have lung cancer. Here are some foods that are good sources of vitamin D:

• Beef liver
• Fortified cereal
• Fish (salmon, sardines, herring, swordfish)
• Cod liver oil
• Egg yolks
• Fortified milk and orange juice
• Fortified yogurt

Potential Benefits of Vitamin D Supplementation for Lung Cancer

Although vitamin D may be known for its health benefits, the direct relationship between vitamin D and lung cancer is complex and still not fully understood. Some studies suggest potential benefits, while others show conflicting results. This finding highlights the need for further research.

Beneficial Properties

While research is still developing, some studies suggest that vitamin D might help to treat and prevent lung cancer. This could be due to vitamin D’s anti-inflammatory, antiangiogenic, and antimetastatic properties.

Anti-inflammatory properties are helpful because inflammation can increase lung cancer risk and prevent apoptosis (the natural process where damaged cells die off). When apoptosis doesn’t happen, damaged cells can multiply, leading to cancer growth.

Vitamin D’s antiangiogenic properties may help slow tumor growth by stopping new blood vessels from forming to supply them with nutrients. Vitamin D may also help stop cancer cells from metastasizing (spreading).

Slowing Cancer Progression

There’s limited research on the relationship vitamin D may have on the progression of lung carcinoma. One study noted that vitamin D may slow the progression of cancer but also concluded that there’s not a direct link to lung cancer risk. Most research from observational studies has shown that there isn’t a connection between vitamin D levels and lung cancer or breast cancer. However, high vitamin D levels have been linked to a lower risk of colorectal cancer and bladder cancer.

Another small study from 2024 showed that having normal levels of vitamin D seemed to help slow cancer progression, but it didn’t change how long people with lung cancer lived. A 2018 study found conflicting results that vitamin D supplementation might help prolong survival for people with early-stage non-small cell lung cancer who have low levels of vitamin D.

Essentially, the data is mixed, and more research is needed to understand the effects of vitamin D on cancer progression.

Treating Vitamin D Deficiency

Researchers don’t have a definitive answer on whether vitamin D supplementation is effective for people with lung cancer across the board. However, they agree that if you have low vitamin D levels — called vitamin D deficiency — taking supplements may be beneficial for your overall health. One MyLungCancerTeam member generally noted, “I had no idea a vitamin deficiency could make such a difference.”

It can be difficult to know if you have a vitamin D deficiency because the symptoms aren’t always obvious or you may not have any symptoms. Symptoms may include fatigue, bone pain, muscle weakness or cramps, and mood changes.

Potential Interactions and Side Effects of Vitamin D Supplements

While vitamin D is generally safe, taking too much can sometimes lead to vitamin D toxicity, which can cause harmful side effects like:

• Nausea and vomiting
• Muscle weakness
• Confusion
• Pain
• Dehydration
• Kidney stones

Vitamin D can interact with certain medications, which is why it’s important to always let your doctor know about all the supplements and vitamins you’re taking.

Are Vitamin D Supplements Right for Me?

Because research on vitamin D and lung cancer is contradictory, it’s important to talk with your health care provider, especially if you’re concerned about your vitamin D status. Your doctor can test you for a vitamin D deficiency and recommend treatment tailored to your needs.

Keep in mind that vitamin D is not a substitute for standard lung cancer treatments. Vitamin D supplementation may be recommended as one aspect of comprehensive cancer care only if you have low blood levels of vitamin D. Because research into the link between lung cancer and vitamin D is ongoing, have open communication with your health care team about your concerns so that you and your doctor can be on the same page about your treatment goals.

Find Your Team

On MyLungCancerTeam, the social network for people with lung cancer and their loved ones, more than 14,000 members come together to ask questions, give advice, and share their stories with others who understand life with lung cancer.

Are you living with lung cancer? Has your doctor recommended monitoring your vitamin D levels or taking supplements? Share your experience in the comments below, or start a conversation by posting on your Activities page.