Rats were given a cancer causing chemical known as N-nitrosomethylbenzylamine (NMBA).
NMBA causes cancer of the esophagus. Scientists freeze dried blackberries,
strawberries and black raspberries. Different rats were supplemented
with one of these berry powders before, during, and after being
exposed to NMBA. At 25 weeks after exposure the rats were examined
and it was found that all three of the berry powders decreased the
number of esophageal tumors (papillomas – tumors on stalks
in the esophagus that are precursors to squamous cell carcinoma)
from 24% to 56% compared to rats not given the berries. The berry
powders prevented NMBA from damaging DNA. In a second study the
animals were first exposed to NMBA and then given either the strawberry
or the black raspberry powder. They decreased the formation of tumors
by 31% to 64% when administered after exposure to the chemical.
Berries therefore inhibit three steps in the cancer process; initiation,
promotion, and progression to cancer. The study appears in the current
issue of the journal Nutrition and Cancer.
Commentary by Jerry Hickey, R.Ph.
Studies show it is not the caffeine which helps decrease
the risk of developing diabetes but probably the polyphenols.