Ep. 12 – Refined fiber and liver cancer
Can refined fiber cause liver cancer? That’s what a recent health headline seemed to suggest. Dr. Chet Zelasko will get into the details of this study to find out if it’s true for everyone on this edition of Straight Talk on Health
Welcome to Straight Talk on Health, I'm your host Dr. Chet Zelasko. Together with WGVU in Grand Rapids, Michigan I examined the latest and greatest in the world of health. Whether it's research that makes headlines, another miracle diet, a new supplement or an exercise trend, I look at the science behind them and then let you know whether it's real or made up. You can check out other things that I do on my website drchet.com and please sign up for my free e-mail.
When we talk about health headlines, how about one that says "diets high in processed fiber may increase cancer risk" - and you've got to be thinking, wait a minute. Fiber can cause cancer? What is that all about? Well, that happened to be the health headline from one of the news feeds I get. Now, part of the problem with some of the news feeds that are out there, if you subscribe to them is that they just take the public relations department promotion and just publish that. That's not really going into detail because the person that interviewed the scientist involved in the research for the press release is from the University. In this case, it's Temple University. Scratch that: University of Toledo, I knew it was a T word. I knew it. And this is something that this scientist has been researching for many, many years and it was curious to them.
Now, one of the things that caught my attention about this, this is not the first time that in this case something like inulin has caught my attention. There are plenty of things that are different types of fibers that have been extracted from plant material and then have been used as fillers or other things in processed foods. To me. I like inulin the best because it is a prebiotic and a probiotic. First, it works as a probiotic because it's food for the good critters that live in your digestive system. But it's also it acts like fiber. And that's the role that is important to me. So the prebiotic is the helps with the digestive system, the probiotic, the prebiotic qualities of it help feed the good bacteria.
You know, it's curious. Doesn't feed the bad bacteria. You know what they need? Refined carbohydrates. Where are we finding inulin more and more often in refined carbohydrates. So when you look at the type of research that they did, we want to see exactly how they did it to be able to determine did they do something that something for us to be concerned about? Or not? Now to me, I used inulin every day together with cilium husks and I will continue to use it. Chicory root, you know that little purple flower? That seems like a weed that's growing next to roads. Well, that's one source of wild chicory root and for some reason that seems to appeal to me and most inulin that you funding, at least if you buy a new and separate comes from chicory root. But it any fruit and vegetable may be able to have that in there.
Now the thing that really addressed the big issue is that process fiber, according to this study, seem to cause a particularly nasty type of liver cancer called paddle cellular carcinoma. Now, we know one thing, headlines are meant to grab your attention. But everything isn’t the way it always appears to be. So let's start with some facts, in United States, 28,600 men and 12,660 women will be diagnosed with all forms of liver cancer in 2022, well, it's not in the top 10 types of cancer. The U.S. has a population of 330 Million. So that's not a huge number. The rates are much higher in less developed countries. And I made a slight mistake. It is in the top 10 of cancers.
Now, here's something else that's a number. The typical intake of all types of fiber is about 14 grams on average. And that's less than half of what the fiber intake should be. Now, depending on your diet, fiber intake should be about 1.4% of the dietary intake by volume. Now, I've always come to the conclusion that all Americans need to increase their fiber intake by eating foods containing fiber and using supplemental fiber or if they need to. Now, what did this research say before you all go out and start getting more fiber? Well, the critical thing it was a genetic defect. That was the underlying problem based on observational studies, researchers examined the role of soluble fiber on metabolic syndrome in mice. Now that makes sense. Increasing fiber is one of the things that you're taught to do. If you have metabolic syndrome and metabolic syndrome for those of you that don't know is a precursor of type 2 diabetes as well as cardiovascular disease. But they didn't just check any type of mice. They used one with the specific defective gene called toll like receptor 5 tlr 5. These mice develop metabolic syndrome when they eat the typical Western diet. So researchers used several types of soluble fiber, including inuliun impact. And while the symptoms associated with metabolic syndrome, in other words, elevated blood sugar, elevated cholesterol, all those things decreased. They discovered that close to half of these tlr 5 mice developed liver cancer.
Well, the normal controls, which are your wild field mice did not. Why? Well based on prior researcher, researchers suspected that something was causing bile acids to enter the bloodstream. Why? Because those mice were [unintelligible] . You know, I know for life and you pretend to understand how you can tell most is jaundiced. But evidently, just like we do, they turn yellow. There's a strain of mice. The number doesn't really matter. That has a defect which causes portosystemic shunt and what that is, it's an abnormal vein, connecting the blood supply. Returning from the intestines to the vain, returning blood to the heart, bypassing the liver.
Now, what happens if that occurs, whether it's in a mouse or human being by last its buildup in the bloodstream that damages the liver and that's what causes liver cancer. The use of high soluble fiber diets speeds up that process because of the fermentation of the fiber by probiotics. So that's why the results associated fiber with cancer. But is it a risk in human beings? I don't think it's a huge risk simply because that portosystemic shunt shouldn't in humans. The risk is about one 30,000. And also remember, you have to have a group of people that are going crazy on fiber intake. It would have to exceed no more than double of what the typical intake would be. But if you wanted to know, just for sure, all you have to do is get a blood test for [by lessons]. If you're [by last that] are higher, then that may put you at that risk. We're not normal fiber intake, but for excessive fiber intake because that was the problem. They gave those mice 10% of their daily intake as fiber to start with in another study, the insulin content alone was 7 and a half percent of their total dietary intake.
Well, that's much more than the 1.4% most humans are supposed to have. And we in that we only get half of that to begin with. I don't see it as a big problem. Is it absolutely true? Yes. Is it relatively meaningless? Also, correct. But I wrote to one of the authors because I wasn't satisfied and they wrote because there was a little thing in there that they had looked at the atbc study. That's the elf to call for beta carotene study and cigarette smokers and what they found and they had dietary data on them. And this is a study from back in the late 80's early 90's and they followed this group of people. And what they found is that those that had reported a higher than normal fiber intake also had an increased risk of liver cancer. The problem being they didn't specifically look at the types of fiber there were available because fiber research is not as advanced as it is today.
And we didn't have as many choices way back then. So what does this mean? You don't have to worry in my opinion about fiber causing liver cancer. What you do have to worry about is making sure that you eat a better diet. And if you are concerned that you might be at risk for some reason, have your bile acid checked called my physician and asked if we could do that. Blood test haven't done it yet. But the extent that we go in for a blood draw, that's where we're going to do just to eliminate the possible. Is it probable not unless we eat a whole lot more junk food because that's typically where you funding not necessarily junk but processed food is where you find high amounts of soluble fiber. It doesn't mean stop eating your fruits or vegetables nor all those hold rate. That's it for that show until next, this is Dr. Chet Zelasko Go saying Health is Jace. People choose wisely today and every day.
Narr: Straight Talk on Health with Dr. Chet Zelasko is recorded in the studios of WGVU Public Radio in Grand Rapids, Michigan. The views and opinions expressed on Straight Talk on Health are not necessarily those of WGVU, its underwriters or Grand Valley State University. Episodes are found at wgvunews.org or wherever you get your podcasts, please rate and subscribe.