Too much of a good thing

The Times reports on a new suggestion about what's good for a healthy prostate:

Eating tomatoes and broccoli in the same meal could help men to fight prostate cancer.

A study suggests that when they are both present in a regular diet, the two foods — known for their cancer-fighting qualities — help to reduce tumours more effectively than when they are eaten separately.

Fine, I happen to like both. But how often should it be eaten?:

They suggest that men should regularly consume servings of up to three quarters of a head of raw broccoli and two to three tomatoes to help fight the disease.

John Erdman, Professor of Food Science and Human Nutrition at the university, said that men should consider consuming three to five such servings a week.

Who on earth likes broccoli that much? I guess it does say "up to", so maybe it is not as much as it sounds.