This is a nice confirmation of something I’ve suspected. That some relatively large molecules pass into the body unchanged in “digestion”; many with biological activity. We all know this from the use of medicines, many of which are fairly large molecules and expected to be absorbed unchanged; yet somehow many folks think things like DNA and RNA and Proteins are all completely and perfectly converted into “raw materials” prior to any getting in…
But it’s just not so.
Digestion, like most processes in our bodies, is an evolved process that is “just good enough” and then doesn’t waste any more energy than needed. Energy being a vital resource, and typically in short supply, to living things. We have various energy conservation strategies. It is so important that most species to NOT evolve a large brain as it is a waste of energy. Humans are very unusual in that regard, but it comes at the cost of massive die offs in times of famine and an inability to just estivate or hibernate. We must be actively seeking calories to keep the brain fed.
So one energy conservation strategy would be to only digest things to the largest sized pieces that can be reused. IMHO that is part of what leads to arthritis, as some of us develop an immune response to “bits” of collagen or other materials from some particular foods. Bits that are just unique enough for the immune system to eventually decide they are “not us”, but are sized such that they can be brought in from food and reused as ‘building blocks’ via chunks that are energy efficient large. A miss match between the digestive “bring in big chunks to be efficient” and the immune system desire for blocks broken down enough to be clearly just ‘raw materials’. So, for me, beef proteins cause an immune response leading to arthritic problems if I eat it more than once a week (or less, some times).
OK, fine theory and all, but not much evidence for it (other than speculation as to a ’cause’ that is a kind of wiggle match to the available evidence of cause / effect).
So along comes this interesting article:
It’s an article about the discovery of an RNA chunk from rice floating around in the blood of animals fed rice. Including people. Not only that, but the microRNA is biologically active.
Now think about that for a minute. A chunk of a PLANT gets passed into the blood unchanged, floats around, and does things.
I took some fair amount of heat from some folks over my assertion that it was time to walk away from GMO foods. (One comment that didn’t get approved said I was “FOS”, or full of it… Telling the host they are ‘full of shit’ does not meet the guidelines of the About box…) I’d stated that my concern was with the potential for the bits of crap inserted into GMO foods to remain active and do “who knows what” in the gut, interacting with gut bacteria and / or having some of it interacting with you. That relatively big bits could be passed wholesale into the body and that could be very “not good”. Things like the BT Toxin.
Well, here we have an ‘existence proof’ of just such a large molecule of biologic material getting into the blood stream and wandering around.
RNAs from rice can survive digestion and make their way into mammalian tissues, where they change the expression of genes.
What’s the News: It’s no secret that having lunch messes with your biochemistry. Once that sandwich hits your stomach, genes related to digestion have been activated and are causing the production of the many molecules that help break food down. But a new study suggests that the connection between your food’s biochemistry and your own may be more intimate than we thought. Tiny RNAs usually found in plants have been discovered circulating in blood, and animal studies indicate that they are directly manipulating the expression of genes.
What’s the Context:
MicroRNAs, or miRNAs, are molecules involved in regulation of gene expression, the transcription of genes into proteins. miRNAs bind to the messenger RNAs that ferry genetic information from DNA to the ribosomes, which translate messenger RNAs into proteins.
When a miRNA binds a messenger RNA, it keeps it from being translated, thus preventing that gene from being expressed.
How the Heck:
This team of researchers at Nanjing University had been studying the miRNAs that circulate in human blood and were surprised to find that some of the miRNAs weren’t homegrown but instead came from plants. One of the most common plant miRNAs was from rice, a staple of their Chinese subjects’ diets. Intrigued, they confirmed with a variety of tests in mice that the miRNA, which, in its native environs, usually regulates plant development, was definitely coming from food.
When they put the rice miRNA in cells, they found that levels of a receptor that filters out LDL, aka “bad” cholesterol, in the liver went down. As it turned out, the miRNA was binding to the receptor’s messenger RNA and preventing it from being expressed, sending receptor levels down and bad-cholesterol levels up. They saw the same effect when they tried it in mice.
Going further, when they fed rice to mice but also gave them a molecule that would turn off the miRNA, the liver receptor bounced back and bad cholesterol levels went down.
The team concludes that miRNAs may be a new class of functional components in food, like vitamins or minerals—even in an animal that’s pretty far removed from their home organism, they can manipulate gene expression and have an effect on nutrition.
Never heard of MicroRNA? Well, the first one was figured out in the 1990s, but it took until the 2000s to get some clue about them, so it’s a relatively new discovery.
The first miRNAs were characterized in the early 1990s. However, miRNAs were not recognized as a distinct class of biological regulators with conserved functions until the early 2000s. Since then, miRNA research has revealed multiple roles in negative regulation (transcript degradation and sequestering, translational suppression) and possible involvement in positive regulation (transcriptional and translational activation). By affecting gene regulation, miRNAs are likely to be involved in most biological processes. Different sets of expressed miRNAs are found in different cell types and tissues.
Aberrant expression of miRNAs has been implicated in numerous disease states, and miRNA-based therapies are under investigation.
The implications of this are huge.
From potentially lending support to the notion that eating raw food matters, to idiosyncratic food differences, to potentially things like the particular processes of Kosher food making a difference. (Does the way a cow is bled change what is left in the meat to get into, and adjust, your genetic activity? Does a shellfish have a miRNA that causes problems, missing in scaly fish?)
So one of the recent fad diets has been the “Wheat Belly” diet. It asserts that modern wheat makes folks fat. Modern wheat is quite different from the wheat of 1800. Might part of that be a miRNA that is present in larger amounts, and, perhaps, shuts down fat metabolism or turns on fat storage?
The fact that when another substance was given with the rice, the miRNA was turned off and the cholesterol elevation blocked, also implies that ‘food combining’ is important. Perhaps those traditional combinations (like fish / rice or rice / soy sauce) are not just flavor matching.
Are some of the food that are “cancer fighting” perhaps turning off the particular genes of cancer cells? Can “brain food” be more than just the proteins, fats, and vitamins in them?
Also left open is the question of: “If miRNA makes it through the gut, what else does?”
So in some very fundamental ways “You are what you eat” since it is demonstrated to be turning on, and off, various genes. I can think of no more basic change to “who you are” than comes from changing what genes are active.
Looks to me like the folks advocating for a more traditional and low processed diet just got a fairly large boost. If we evolved, for example, to be properly balanced in energy and growth, when eating a kg or so of raw vegetables per day, maybe “that matters”. Perhaps all those folks “juicing” on things like pureed carrots are not just imagining that it makes them feel better.
For me, it mostly means that I’m going to be paying much closer attention to how I feel after eating particular individual foods. I’m also going to try eating some more, and different, raw foods. Now I don’t expect to notice a lot; but it would be very interesting if something were notable. It also means that if something is “less than fresh” I’m going to be wondering what all the “bugs” in it might have contributed, and do I really want a bit of mold to be turning my genes on and off?
There is also the potential to explain some of the longevity “hot spots” via the foods they eat. For example, the folks in Italy who live to 100+ in good shape while eating pounds of sheep cheese. Perhaps it isn’t just the running around chasing sheep, but “something in the cheese” (Pecorino)… So could having cheese, wine, and bread be more than just some calories?
Pecorino Cheese – the answer to a long life?
By Jennifer Meier,
So did anyone else catch The Oprah Show yesterday? The show is visiting regions of the world where a large percentage of the population lives well into their nineties and beyond. Sardinia, off the coast of Italy, is one of the those regions. Giovannai, a 105 year-old resident of Sardinia shared his secret to longevity: “I eat bread, cheese and dark wine.” He is truly a man after my own heart.
According to Oprah’s sidekick Dr. Oz, the Pecorino cheese that Sardinia is known for is rich in Omega-3 fatty acids. Paired with antioxidant-rich red wine and whole grain bread, a dinner of bread cheese is not something you have to view as a guilty pleasure.
Maybe it’s more than just Omega-3s and antioxidants. Perhaps it’s doing a bit of gene regulation as well…
Me? I think I’m going to pick up some Pecorino, a nice rich Italian whole wheat crusty bread, some olive oil to dip it, and a bit of a decent Italian Red… Oh, and a salad…