New research is strengthening evidence that following mom's admonition
to eat your vegetables may be some of the best health advice around.
A large study of 500,000 American retirees has found that just one
extra serving of fruit or vegetables a day may reduce the risk of
developing head and neck cancer.
Numerous studies have demonstrated that diet plays a role in cancer.
Cancer experts now believe that up to two-thirds of all cancers come from
lifestyle factors such as smoking, diet and lack of exercise.
"It may not sound like news that vegetables protect from cancer, but
there is actually some controversy in the literature. It is important that
we do these large studies," said Dr. Alan Kristal, associate head of the
cancer prevention program at Fred Hutchinson Cancer Research Center in
Seattle.
Researchers at the National Cancer Institute queried men and women aged
50 and older about their diets, then followed participants for five years
to record all diagnoses of head and neck cancer, which is the
sixth-leading cause of cancer-related death worldwide.
Tobacco and alcohol use increase the risk of head and neck cancers,
which affect the mouth, nose, sinuses and throat.
The study found eating six servings of fruit and vegetables per day per
1,000 calories cut the risk of head and neck cancer by 29 percent compared
to eating one and a half servings.
The typical adult consumes around 2,000 calories a day.
"Increasing consumption by just one serving of fruit or vegetables per
1,000 calories per day was associated with a 6 percent reduction in head
and neck cancer risk, said Neal Freedman, cancer prevention fellow at the
NCI.
A second study of food consumption in more than 183,000 residents of
California and Hawaii found that a diet high in flavonols might help
reduce pancreatic cancer risk, especially in smokers.
Flavonols are common in plant-based foods
but are found in highest concentrations in onions, apples,
berries, kale and broccoli.
The study found that people who ate the largest amounts of flavonols
had a 23 percent reduced risk of developing pancreatic cancer compared to
those who ate the least.