Researchers Uncover How a Popular Gym Supplement "Creatine" Could Help the Immune System Attack Cancer

For years, creatine has been known as a popular supplement among athletes, bodybuilders, and fitness enthusiasts. It is widely used to improve strength, increase muscle performance, and support recovery after exercise. Now, a new scientific study suggests that creatine may have another remarkable ability—helping the immune system fight cancer.

Researchers at the University of California, Los Angeles (UCLA) have discovered that creatine does more than support muscles. Their findings show that it can energize important immune cells that play a critical role in identifying and attacking cancer. The study, published in the journal iScience, reveals that creatine helps power dendritic cells, which are often described as the “teachers” of the immune system.

This discovery builds on earlier research from the same team showing that creatine boosts the activity of killer T cells, the immune system’s main cancer-fighting soldiers. The new study shows that creatine supports not only the fighters but also the cells responsible for directing and activating them.

Why Dendritic Cells Matter

The immune system is made up of many different types of cells that work together to protect the body. Among the most important are dendritic cells. These specialized cells search for signs of danger, including cancer cells. When they find a threat, they collect pieces of the tumor and present them to killer T cells, effectively teaching them what to attack.

Without properly functioning dendritic cells, T cells cannot launch an effective response against cancer. This makes dendritic cells a crucial part of the body’s defense system.

Most modern cancer immunotherapies focus directly on activating T cells. While these treatments have transformed cancer care, they do not work for everyone. In fact, only about 20% to 40% of patients respond successfully to current immunotherapy treatments.

Scientists believe that strengthening dendritic cells could help more patients benefit from immunotherapy.

A Clue Hidden Inside Tumors

To better understand how dendritic cells function in cancer, the UCLA research team studied tumors in mice. They examined which genes were most active inside dendritic cells that had entered tumors.

One gene immediately stood out. The gene responsible for producing the creatine transporter—a protein that allows cells to absorb creatine—was much more active in tumor-associated dendritic cells than in those found in healthy tissue.

This finding suggested that creatine might be especially important for dendritic cells operating inside the challenging environment of a tumor.

What Happens Without Creatine?

To investigate further, the researchers created dendritic cells that lacked the creatine transporter. These cells could no longer efficiently take in creatine.

The results were striking.

Without access to creatine, dendritic cells struggled to survive. They became less active and were far less effective at preparing T cells to attack cancer.

When these creatine-deficient dendritic cells were grown alongside T cells in laboratory experiments, the T cells divided less frequently and produced fewer immune-signaling molecules needed to fight tumors.

In simple terms, removing creatine weakened the entire immune response.

Testing the Opposite Approach

After seeing the negative effects of creatine deficiency, researchers wondered whether increasing creatine levels could improve immune performance.

To test this idea, they gave daily creatine injections to mice with melanoma, a serious form of skin cancer.

The results were encouraging.

Tumor growth slowed significantly in the mice receiving creatine. The tumors also contained larger numbers of activated dendritic cells. These energized immune cells released higher levels of chemical signals that attracted additional immune cells into the tumor environment.

This created a stronger and more coordinated attack against cancer.

How Creatine Powers Immune Cells

The team used advanced metabolomics techniques to understand exactly how creatine was helping dendritic cells.

They found that creatine increased levels of ATP, the molecule often called the body’s energy currency. ATP provides the fuel needed for nearly every cellular activity.

Tumors are highly competitive environments where cancer cells consume large amounts of nutrients. Immune cells often struggle to obtain enough energy to function effectively.

Creatine appears to act like a rechargeable battery for dendritic cells. It helps them store and access energy when needed, allowing them to remain active even when nutrients are limited.

This steady energy supply keeps important inflammatory signaling pathways running, enabling dendritic cells to maintain their cancer-fighting functions.

Human Cell Experiments Show Similar Benefits

The researchers did not stop with animal studies. They also tested creatine on human dendritic cells grown in laboratory conditions.

Once again, the results were promising.

Creatine-treated human dendritic cells became more active and better at stimulating human T cells against cancer-related targets.

This finding could be especially important for dendritic cell vaccines, a form of cancer treatment that uses specially prepared immune cells to trigger anti-cancer responses.

Scientists believe that adding creatine during the manufacturing process of these vaccines could potentially make them more powerful and effective.

A New Tool for Cancer Immunotherapy

According to the researchers, creatine may have two major future applications in cancer treatment.

First, it could potentially be used as a supportive supplement for patients already receiving immunotherapy, helping their immune systems respond more effectively.

Second, it could be incorporated into the production of dendritic cell-based cancer vaccines to improve their ability to activate immune responses before being administered to patients.

These possibilities remain theoretical for now, but they highlight the broad potential of this simple and widely available compound.

Important Caution: Not Yet Proven in Patients

Although the findings are exciting, the researchers stress that this work is still in the early stages.

The study was conducted using mice and laboratory-grown human cells. It has not yet been tested in cancer patients, and no conclusions can be drawn about whether creatine supplementation improves cancer outcomes in humans.

Creatine monohydrate has been used safely by many people for decades when taken at recommended doses. However, anyone undergoing cancer treatment should speak with their healthcare provider before taking any supplement.

The experimental approaches described in the study have not been approved by the U.S. Food and Drug Administration (FDA) for cancer treatment.

Looking Ahead

The UCLA team hopes to work with physicians to launch future clinical trials that will test whether creatine can enhance cancer immunotherapy in real patients.

If those studies confirm the current findings, creatine could become a simple, affordable tool for strengthening the immune system’s ability to detect and fight cancer.

For now, the research offers a fascinating new insight into how the immune system works. What was once known mainly as a muscle-building supplement may one day play a role in helping the body wage war against one of humanity’s most challenging diseases.

While much more research is needed, the discovery highlights the growing understanding that energy metabolism is a powerful factor in the fight against cancer—and creatine may be an important part of that story.

Reference: Elliot Kang et al, Creatine uptake promotes dendritic cell activation and enhances antitumor immunity, iScience (2026). DOI: 10.1016/j.isci.2026.115436