Whoever concocted the phrase “You are what you eat” was more accurate about our bodies than he ever knew.
According to researchers, not only do the natural substances in certain plants help keep us safer from problems like cancer and heart disease, in some cases they can intervene in the genetic workings of our cells.
As a matter of fact, detailed studies now demonstrate that the genetic material from plants alters how our genes express themselves and influences the production of proteins in ways that can shrink the risk of cancer. This alteration of genetic expression by outside influences is called “epigenetics.” It’s become a big thing in cancer research.
One epigenetic champion turns out to be broccoli. . .
9 November 2016
Newsletter #655
Lee Euler, Editor
Lee Euler, Editor
From broccoli’s genes to yours
For a while now, researchers have been arguing over the likelihood that genetic material from vegetables like broccoli survive their trip down the digestive tract and enter the body more or less intact and ready to help our genes function.
Until recently the argument for and against this possibility seemed pretty evenly pitched. Evidence goes both ways – with some studies apparently showing the genetic material broken apart by digestion and others finding evidence of this material intact in the bloodstream.
But now the most advanced analyses clearly indicate that after you eat vegetables like broccoli, your blood becomes home to alien genetic material – from the vegetables. And this material – known as microRNA or miRNA – can take part in cellular processes to fight cancer.
Help your genes express themselves better
RNA (ribonucleic acid) is primarily a messenger molecule that cells use to transfer instructions from DNA to other parts of the cell. The instructions are for making proteins that take part in cellular processes. MicroRNAs are small RNA molecules that affect the function of other RNAs in the cell.1
Researchers believe the malfunction of RNA often plays a role in the development of cancer. Consequently, if microRNAs from broccoli or other vegetables can “silence” misbehaving RNA or alter gene expression in other ways, they could lower the risk of cancer.
Now, lab tests in China show that this can be happening after you eat broccoli.2
To further investigate this interaction, researchers at the University of Toronto and other Canadian institutions went beyond the lab and analyzed, in tests on people, what happens to microRNAs from broccoli that could potentially interact with 11 different genetic sites that are involved with the development of lung cancer.
They compared blood samples from people who regularly eat broccoli and other cruciferous vegetables (like cabbage and Brussels’s sprouts) with blood from folks who rarely eat these vegetables. Their analysis confirmed that vegetable microDNA was circulating in the blood of the vegetable consumers.3
While they were at it, they also tested cooking methods to see what best preserved the microRNA in broccoli and could lead to the best health results. What they found confirms what other experts have said is the best way to prepare vegetables: Cook them briefly or eat them raw. In contrast, “long exposure to hot water, steaming and blending degrade microRNAs’ integrity, reducing the potential benefits.”4
Then, in lab tests, the Canadians also showed that the microRNAs from eating broccoli, once in a person’s blood, can enter cells and stop processes that might otherwise lead to cancer.
In general, what they found is that a combination of both the microRNAs from broccoli and other chemicals in the vegetable called isothiocyanates (which includes sulforaphane and diindolylmethane or DIM) seem to be necessary to help coax genetic functions away from cancerous activities.
While the Canadian researchers don’t consider their research to be absolutely conclusive, they do point out that their results show the more broccoli you eat, the more of these microRNAs you probably have circulating in your body – although at some point, if you eat this vegetable every day, the amount your body takes up plateaus and stops increasing.5
Keeping genes under control
However, it isn’t only this genetic material from broccoli that can keep cells and their genes under control and less likely to succumb to cancer. Various studies show that the isothiocyanates in broccoli – even without the microRNA – also can cause epigenetic effects that tame rogue genes – deactivating them and keeping them from being expressed.
Sulforaphane is probably the most investigated isothiocyanate. It’s even extracted and sold as a supplement. Research at the Linus Pauling Institute at Oregon State University demonstrates that sulforaphane can restrict the activity of a group of enzymes that can obstruct the functions of genes that are supposed to stop the development of tumors.6
Aside from inhibiting these troublesome enzymes, sulforaphane can play another epigenetic role by speeding up what’s called DNA methylation (a process that changes the molecular structure of DNA and alters its function).
“It appears that DNA methylation and HDAC [enzyme] inhibition, both of which can be influenced by sulforaphane, work in concert with each other to maintain proper cell function,” says researcher Emily Ho, Ph.D.. “They sort of work as partners and talk to each other.”
According to Dr. Ho, this kind of molecular tag team wrestling involving these processes improves cell functions and keeps cellular division under tight control, preventing the wild kind of reproduction that takes place during cancer.
“Cancer is very complex and it’s usually not just one thing that has gone wrong,” Dr. Ho points out. “It’s increasingly clear that sulforaphane is a real multi-tasker. The more we find out about it, the more benefits it appears to have.”
She further explains that DNA methylation is a normal process that switches off genes, and is part of the process that limits which DNA material gets communicated in each cell. Harmful alterations in methylation can increase the risk of cancer.
“With these processes, the key is balance,” Dr. Ho says. “DNA methylation is a natural process, and when properly controlled is helpful. But when the balance gets mixed up it can cause havoc, and that’s where some of these critical nutrients are involved. They help restore the balance.”
Good news ahead
The really good news about these discoveries is that there is probably much more ahead. Broccoli and other cruciferous vegetables contain a wealth of other chemicals classified as isothiocyanates. These other isothiocyanates have already been shown to help make radiation more effective against tumors,7 slow the growth of cancer8 and kill cancer cells without affecting normal cells.9
Originally, broccoli was cultivated by the ancient Romans, who referred to the plant as the “five fingers of Jupiter” – probably because of its powerful benefits on health. If you put your five fingers around it and eat it raw, your body will absorb most of its isothiocyanates.
If you do cook it, just cook it lightly; don’t steam it for more than four minutes – otherwise you may eliminate some of its most important anti-cancer ingredients.
