New research on cancer and aging suggests that adding more broccoli and green tea to your diet can help control genes that play a key role in cancer development.
Aging, cancer and diet are part of exciting new research led by Trygve Tollefsbol, PhD, Professor of Biology and Senior Scientist at the Comprehensive Cancer Center and Center for Aging at the University of Alabama at Birmingham.
Dr. Tollefsbol is studying telomeres, repetitive stretches of DNA located at the ends of chromosomes. Telomeres protect chromosomes the way the plastic tips of shoelace keep them from unraveling. Each chromosome contains DNA, which holds the genetic blueprint of a cell.
Cell division is needed to grow new skin, blood, bone and other cells. In many types of cells, telomeres get a little bit shorter every time a cell divides. Eventually, when the telomeres become too short, the cell no longer divides or it dies. (The rate at which this happens may contribute to the rate at which we age, but this research is only in the early lab-level stage.)
An enzyme (a protein in our bodies) provides instructions for adding telomeres to the ends of chromosomes. This enzyme is called telomerase. A gene called"hTERT" controls telomerase activity. The more cells divide, the more telomerase is activated. When cancer occurs, most cancer cells that are dividing out of control have telomerase activity that makes them "immortal." They don't age naturally and become mortal as normal cells do.
Normally, hTERT is switched off early in an embryo's development. "It is thought this inactivation protects against cancer," Dr. Tollefsbol explains. Eventually, however, some normal cells may mutate and turn on the hTERT gene, causing telomerase production and predisposing a person to developing cancer.
Dr. Tollefsbol's goal is to treat cancer by selectively inhibiting telomerase so that cancer cells will be destroyed while normal cells remain unaffected.
Dr. Tollefsbol's research is showing exciting results: substances in plant foods may be able to reverse telomere shortening – and cell aging – by controlling telomerase.
The compound sulforaphane in cruciferous vegetables – such as broccoli, cabbage and kale – may inhibit telomerase in cancer cells. "We think it's important in terms of why eating vegetables, especially cruciferous vegetables, can help prevent cancer," he says. Dr. Tollefsbol's lab findings suggest that just a cup of broccoli sprouts a day may help to prevent cancer. He advises eating plenty of cruciferous vegetables (such as broccoli, cabbage and cauliflower) if you can't find broccoli sprouts.
A compound in green tea also appears to keep telomerase inactive, he says. Drinking a few cups of green tea daily seems to control telomerase and may have a cancer-fighting effect.