A new study led by researchers at UCLA Health offers hopeful news for men with early-stage prostate cancer.
The study shows that changing your diet—specifically eating less omega-6 fats and more omega-3 fats, along with taking fish oil supplements—might slow the growth of cancer cells.
The research focused on men with low-risk prostate cancer who chose active surveillance. This approach means the cancer is monitored closely with regular tests, but no immediate surgery or radiation is done.
Many men prefer this option to avoid side effects of treatment. However, within five years, around half of these men eventually need more aggressive therapy. That’s why many are looking for ways to slow cancer growth and delay treatment.
The study, called CAPFISH-3, was published in the Journal of Clinical Oncology. It included 100 men who had either low-risk or favorable intermediate-risk prostate cancer.
These men were randomly split into two groups. One group continued their regular diet. The other group received counseling from a dietitian and followed a special diet low in omega-6 fats and high in omega-3 fats. This group also took fish oil supplements.
Omega-6 fats are commonly found in foods like chips, cookies, mayonnaise, and fried or processed foods. Omega-3 fats are found in fish like salmon, and in fish oil. The goal of the diet was to create a better balance between these two types of fats.
Patients in the diet group were also taught to make healthier food choices, like using olive oil or lemon juice instead of creamy dressings.
The main goal of the study was to see if this diet change would affect the growth rate of cancer cells. To measure this, the researchers used a test called the Ki-67 index. This test looks at how fast cancer cells are multiplying. A lower number means the cancer is growing more slowly.
At the beginning of the study, all participants had a biopsy to measure their Ki-67 levels. After one year, they had another biopsy from the same area of the prostate. The results were clear. The men who followed the diet and took fish oil had a 15% decrease in their Ki-67 score. In contrast, the men who didn’t change their diet saw a 24% increase.
Dr. William Aronson, the lead author of the study, said that this result shows diet can play a meaningful role in prostate cancer management. Even though other cancer markers like the Gleason score didn’t change, slowing cancer cell growth is still a big step.
Dr. Aronson is a professor of urology at UCLA and also works at the West Los Angeles VA Medical Center. He says this finding is important because many men want to take action and feel in control of their health. Changing your diet is a simple step that could delay the need for surgery or radiation.
Still, the researchers say more studies are needed to see if these changes can help in the long term. They hope to run larger trials to learn whether adjusting fat intake can not only slow cancer growth but also improve survival rates.
For now, the study provides strong evidence that a healthy diet, along with fish oil, may help men with prostate cancer manage their condition while on active surveillance.
If you care about prostate cancer, please read studies about 5 types of bacteria linked to aggressive prostate cancer, and new strategy to treat advanced prostate cancer.
For more information about prostate cancer, please see recent studies about new way to lower risk of prostate cancer spread, and results showing three-drug combo boosts survival in metastatic prostate cancer.
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