A high-vegetable diet during active surveillance for prostate cancer

Evidence label: No demonstrated cancer-control benefit · Clinical goal: delay progression in early prostate cancer managed with active surveillance

Evidence at a glance

Population: 478 men with localized prostate cancer on active surveillance.
Intervention: telephone counseling to reach at least seven daily vegetable servings, including cruciferous vegetables and tomato products, versus written dietary information.
Result: the intervention changed eating behavior but did not reduce clinical progression over two years.

What was studied

The phase III MEAL trial randomized 478 men: 237 to a structured telephone-counseling program and 241 to usual written information. The primary analysis included 443 participants.

Progression was a composite of prostate-specific antigen changes, biopsy findings or treatment for prostate cancer. This is a cancer-control endpoint, not a symptom or biomarker-only question.

What the evidence shows

There were 245 progression events: 124 in the counseling group and 121 in control. The unadjusted hazard ratio was 0.96 (95% CI 0.75–1.24); the adjusted hazard ratio was 0.97 (95% CI 0.76–1.25).

The intervention successfully increased vegetable intake, but that behavioral change did not translate into less progression during the study period.

Limits and uncertainty

Follow-up was two years, and the composite endpoint includes several kinds of progression. The trial does not answer whether a generally healthful diet affects cardiovascular health, longer-term outcomes or other cancers.

The result tests this intensive dietary program in this population; it does not show that vegetables are harmful or unimportant for overall nutrition.

Safety and practical context

A food-based vegetable pattern is generally compatible with prostate-cancer care, but major dietary changes can affect weight, bowel symptoms and anticoagulation management. Supplements or extracts are not equivalent to the foods tested.

Do not delay recommended monitoring, biopsy or treatment because of diet.

Questions for the care team

What is the purpose of changing my diet—general health, weight, treatment tolerance or cancer control?
Could this plan unintentionally cause weight loss or conflict with another medical condition?
What active-surveillance tests and decision points still apply?

Sources

Literature searched: October 14, 2026 · Record appraised: October 14, 2026

Educational evidence summary, not personal medical advice. Supportive approaches should complement—not replace—appropriate cancer treatment and symptom management.