Scientists from Université de Montréal have made an exciting discovery about a small fruit from the Amazon rainforest called the camu-camu berry.
This berry is already known for being very healthy—it’s packed with vitamin C and antioxidants, and past studies have shown it can help protect against obesity and diabetes. But now, researchers think it might also play a role in fighting cancer.
The reason for this is a natural substance in the berry called castalagin. This is a type of polyphenol, a group of plant chemicals known for their antioxidant and anti-inflammatory effects.
Antioxidants help the body fight off damage caused by harmful molecules, and anti-inflammatory compounds can reduce swelling and irritation inside the body. But castalagin does something even more interesting—it supports the growth of healthy bacteria in the gut.
Why does this matter for cancer treatment? It turns out that the tiny organisms living in our digestive system, known as the gut microbiome, have a big impact on how our immune system works. A healthy gut microbiome can help the body fight off illness and respond better to medical treatments, including cancer therapies.
The type of cancer treatment this discovery focuses on is called immunotherapy. This treatment helps the body’s own immune system find and kill cancer cells.
One kind of immunotherapy, called immune checkpoint inhibitors (or ICIs), has saved lives for some people with cancers like melanoma and lung cancer. However, these drugs don’t work for everyone—only a small number of patients respond well.
That’s where castalagin might make a big difference. In recent research using mice, scientists gave castalagin to the animals by mouth. The results were promising: castalagin changed the balance of bacteria in the mice’s guts and helped boost their immune response to cancer.
This suggests that taking castalagin could make immunotherapy more effective, especially for people whose bodies don’t currently respond well to it.
The next step is to test this in humans. A clinical trial is about to begin, involving 45 patients with either lung cancer or melanoma. These patients will receive castalagin along with their regular immunotherapy treatment. Scientists hope that this combination will help more patients respond to the therapy and fight off their cancer more successfully.
If this trial goes well, it could change how doctors treat certain cancers. Instead of relying only on drugs, doctors may begin using natural compounds—like those found in the camu-camu berry—to support the body and improve existing treatments. It’s a good example of how modern medicine and natural remedies can work together.
Camu-camu berries have already earned attention for their health benefits, especially due to their very high vitamin C content—higher than almost any other fruit. Now, with this new research, they might prove useful in treating some of the most difficult cancers.
Of course, it’s still early days. More research is needed to understand exactly how castalagin works and how effective it can be in people. But this discovery gives hope that something as simple and natural as a berry from the rainforest could one day help save lives. Scientists are now exploring how nature’s own ingredients could become a powerful part of the future of cancer care.
If you care about cancer, please read studies about vitamin D and bowel cancer, and a cautionary note about peanuts and cancer.
For more health information, please see recent studies about the link between ultra-processed foods and cancer, and everyday foods to ward off pancreatic cancer.
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