A dietary intervention focused on increasing omega-3 fatty acid consumption may help slow the progression of prostate cancer in men who opt for active surveillance rather than immediate treatment, according to new research from the University of California, Los Angeles (UCLA).
The study, published December 12 in the Journal of Clinical Oncology, offers promising evidence that dietary modifications could extend the period during which men with low-risk prostate cancer can safely delay more aggressive interventions.
Dietary Intervention Shows Measurable Impact on Cancer Markers
Researchers led by Dr. William Aronson, professor of urology at UCLA and chief of urologic oncology at the West Los Angeles Veterans Affairs Medical Center, conducted a randomized trial involving 100 men diagnosed with low- or favorable intermediate-risk prostate cancer who had chosen watchful waiting approaches.
Half the participants were randomly assigned to continue their normal diets, while the other half received counseling to increase their omega-3 fatty acid intake through fish oil supplements while simultaneously reducing consumption of omega-6 fatty acids commonly found in processed foods.
"Many men are interested in lifestyle changes, including diet, to help manage their cancer and prevent the progression of their disease," noted Dr. Aronson. "Our findings suggest that something as simple as adjusting your diet could potentially slow cancer growth and extend the time before more aggressive interventions are needed."
Significant Differences in Cancer Cell Proliferation
To track the impact of dietary changes, researchers monitored each participant's Ki-67 index, a biomarker that measures the rate at which prostate cancer cells multiply.
After one year, the results were striking:
- Men who increased omega-3 intake showed a 15% decline in their Ki-67 index
- The control group following their usual diets experienced a 24% increase in Ki-67
This 39-percentage-point difference suggests the dietary intervention may significantly slow cancer progression, potentially delaying or preventing the need for surgery, radiation, or drug therapy.
Clinical Context and Implications
The findings are particularly relevant given current prostate cancer treatment guidelines, which increasingly support active surveillance for men with slow-growing tumors. However, approximately half of patients who choose this approach require more aggressive treatment within five years of diagnosis.
"This significant difference suggests that the dietary changes may help slow cancer growth, potentially delaying or even preventing the need for more aggressive treatments," Aronson explained.
The study builds on growing evidence regarding the potential anticancer properties of omega-3 fatty acids. A separate large-scale analysis of over 253,000 participants from the UK Biobank, published in the International Journal of Cancer, found that higher omega-3 levels correlated with lower rates of several cancer types, including colon, stomach, and lung cancers.
Study Limitations and Future Research
Despite the encouraging results, the researchers noted an important limitation: while the omega-3-rich diet positively affected Ki-67 indices, it did not impact Gleason grade scores, another common measurement of prostate cancer progression.
This discrepancy highlights the need for larger, longer-term studies to determine whether dietary interventions can meaningfully extend the period of active surveillance and improve overall clinical outcomes for prostate cancer patients.
The research team emphasized that further investigation is needed to confirm whether increasing omega-3 intake has lasting effects on prostate cancer outcomes and to determine optimal dosing strategies.
Practical Implications for Patients
For men currently under active surveillance for prostate cancer, these findings suggest a potential dietary strategy that could complement medical monitoring. The intervention focused on two key components:
- Increasing omega-3 fatty acid intake through fish oil supplements
- Reducing consumption of omega-6 fatty acids found in processed foods like chips, cookies, and fried items
While this dietary approach shows promise, patients should consult with their healthcare providers before making significant changes to their treatment plans or supplementation regimens.
The study adds to a growing body of evidence suggesting that nutritional interventions may play an important role in comprehensive cancer management strategies, particularly for slow-growing malignancies where delaying progression could significantly improve quality of life.
