A report published in the January 15, 2007 issue of the journal Cancer Research concluded that a diet enhanced with tomato and broccoli powder was better than one containing either nutrient alone at shrinking prostate tumors in rats.
Food science and human nutrition professor John Erdman and colleagues at the University of Illinois and Ohio State University conducted the current research on rats with implanted prostate cancer tumors. The animals were divided to receive diets containing 10 percent broccoli powder, 10 percent tomato powder, or both. Other rats received lycopene (the red pigment in tomatoes and other red fruits) or finasteride (a drug used to treat prostate enlargement), or were surgically castrated.
After 22 weeks of treatment, rats who received the combination of broccoli and tomato powder experienced greater shrinkage of their tumors as determined by tumor weight than animals in any other group. Biopsies confirmed the reduction in proliferation in this group compared to the others, with the exception of the castrated rats whose tumor shrinkage approached that of the broccoli-tomato group.
“As nutritionists, it was very exciting to compare this drastic surgery to diet and see that tumor reduction was similar,” stated research team member and report coauthor Kirstie Canene-Adams. “Older men with slow-growing prostate cancer who have chosen watchful waiting over chemotherapy and radiation should seriously consider altering their diets to include more tomatoes and broccoli.”
“When tomatoes and broccoli are eaten together, we see an additive effect, Dr Erdman explained. “We think it’s because different bioactive compounds in each food work on different anticancer pathways.”
“To get these effects, men should consume daily 1.4 cups of raw broccoli and 2.5 cups of fresh tomato, or 1 cup of tomato sauce, or ½ cup of tomato paste,” Canene-Adams suggested.
Other research conducted at the University of Illinois by Dr Erdman’s colleague Elizabeth Jeffrey discovered that sulfur compounds in broccoli enhance enzymes in the body that degrade cancer-causing substances. “For ten years, I’ve been learning how the phytochemicals in tomatoes affect the progression of prostate cancer,” Dr Erdman stated. “Meanwhile Dr Jeffery has been investigating the ways in which the healthful effects of broccoli are produced. Teaming up to see how these vegetables worked together just made sense and certainly contributes to our knowledge about dietary treatments for prostate cancer.”