Do Cell Phones Cause Brain Tumors?

What does the world’s leading authority on carcinogens have to say about mobile phones?

Do cell phones cause cancer? That’s a question billions of people would like to have answered and one I address in my video Cell Phone Brain Tumor Risk?. That’s why we have the World Health Organization’s International Agency for Research on Cancer (IARC), the recognized authority on determining what is and is not carcinogenic. There are five categories: Group 1 carcinogens are agents that we know with the highest level of certainty do cause cancer in human beings, Group 2A probably cause cancer, Group 2B possibly cause cancer, we’re not sure about agents categorized as Group 3, and Group 4 agents probably don’t cause cancer.

In May 2011, 30 scientists from 14 countries met at the IARC to assess the carcinogenicity of the radiation emitted from cell phones and concluded that, given the limited amount of available evidence, cell phones are “‘possibly carcinogenic to humans’ (Group 2B).” So they’re not classified as a Group 1 carcinogen that’s known definitively to be cancer-causing, like plutonium, or processed meat, or as probable carcinogen, like DDT, Monsanto’s Roundup pesticide, or some regular meat, but they are classified as a possible carcinogen, ranked similarly as preserved vegetables like kimchi. 

Now, this classification was made more than five years ago. Evidence continues to mount, and the latest two 2017 systematic reviews found a 33 percent increase in odds of brain tumors with long-term use and showed 46 percent higher odds for tumors on the phone side of your head—and the reviews included the industry-funded studies that have been accused of being biased and flawed, and underestimating the risk, as opposed to independent studies free from “financial conditioning.” How’s that for a euphemism? Given this, some scientists are pushing to have the IARC reclassify cell phones as probable carcinogens or even bump them all the way up into Group 1, at least for brain cancer and acoustic neuroma, a type of inner ear tumor. 

But the IARC classification for cell phones currently remains at possible carcinogen. What does that mean? What do we do with that information? Well, given the uncertainty, we could follow “the precautionary principle” and use simple personal measures to reduce our exposure, like not putting the phone directly up to our head all the time. Indeed, the “main concern about cell phones is that they are usually held close to the head,” which is considered particularly important for children. There’s no evidence of finger cancer, though, so you can keep texting away. 

Other potential personal recommendations include waiting a moment before putting your cell phone to your ear, if you don’t have a headset, because “when the cell phone establishes a connection, the emission is high.” And don’t fall for those anti-radiation gizmos, those “so-called protection covers,” as they may make things worse by forcing the phone to boost the signal.

Not all agree, however, with this precautionary approach. Employees at two cell phone industry trade organizations emphasize “there are many aspects of human activity that are not ‘totally without adverse health effects,’—for example, transport (including aviation) and hot showers,” so they suggest we should just accept the risk as being worth it. Wait. Hot showers? As in we might scald ourselves or something? In any case, they further suggest that we shouldn’t put forth any recommendations because “such judgment should be made by parents on a personal basis for their own children,” and, if we do put out guidelines or something, people might get nervous and we all know “anxiety itself can have deleterious health consequences.” So, basically, the cell phone industry cares so much about your health that it doesn’t want you worrying your pretty little head.

Nevertheless, all of this is openly discussed in the risk analysis literature. “From a public health perspective, it might be reasonable to provide cell phone users with voluntary precautionary recommendations for their cell phone handling in order to enable them to make informed decisions”—but what if the public can’t handle the truth? We don’t want to freak people out. There’s still “scientific uncertainty” and we don’t want to “foster inappropriate fears.” For example, brain cancer is rare to begin with. You only have about a 1 in 15,000 chance a year of getting a brain tumor,  so even if cell phones double your risk, that would only take you up to a 1 in 7,500 chance. You may be more likely to get killed by a cell phone in the hands of a distracted driver than by cancer. So, whether health authorities want to inform the general public about precautionary possibilities really remains more of a political decision.


For more on cell phones and Wi-Fi, see:

What was that about meat and cancer? See my video Carcinogens in Meat. And, to learn more about the IARC’s decision and the industry’s reaction, see:

What about cancer risk of medical diagnostic radiation? See:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

Can Cell Phone Radiation Damage Your DNA?

Do mobile phones cause brain tumors? Whenever a trillion-dollar industry is involved—whether it’s Big Food, Big Tobacco, Big Pharma, or Big Telecom—there’s so much money that the science can get manipulated.

When it comes to the potential human health effects of cell phone use, certainly, you might end up with a crick in your neck if you text excessively or even break your neck or the neck of someone you may hit if you text while driving. On the other hand, think of the countless lives that have been saved on the road, because people are now able to so quickly phone in emergencies. 

But what about cancer? Since the turn of the century, there have been studies suggesting up to double the risk of brain tumors with long-term cell phone use on the side of your head you use to talk. That’s important, because the radiation only really penetrates up to a couple of inches into your brain. At 0:48 in my video Does Cell Phone Radiation Cause Cancer?, I show views from the back of the head and the top of the head, and you can see why you might develop cancer on one side of the head over the other.

Since it’s such a local effect, you can see why there are recommendations for using the speakerphone function or a hands-free headset, which can reduce brain exposure by a factor of 100 or more—and this includes Bluetooth headsets. This may be particularly important in children, who have thinner skulls. 

Cell phone radiation isn’t like nuclear radiation, though. It doesn’t damage DNA directly, like gamma rays from an atomic bomb. Yes, but it does appear to be able to damage DNA indirectly by generating free radicals. Out of 100 studies that looked at this, 93 confirmed these oxidative effects of the kind of low-intensity radiofrequency radiation that comes out of cell phones. Okay, but does that oxidative stress translate out into DNA damage? Most studies found it did, detecting signs of genotoxicity, which is damage to our genes, DNA, or chromosomes. A lot of those studies were done in petri dishes or in lab animals, though. I’m less interested in whether Mickey or Minnie is at risk than I am concerned about brain tumors in people. Yes, some population studies found increased cancer risk, but other studies did not. 

Could the source of funding for those studies have anything to do with the different findings? Some of the studies were funded by cell phone companies. Researchers “hypothesized that studies would be less likely to show an effect of the exposure if funded by the telecommunications industry, which has a vested interest in portraying the use of mobile phones as safe.” So, they ran the numbers and—surprise, surprise—“found that the studies funded exclusively by industry were indeed substantially less likely to report statistically significant effects…” 

Indeed, most of the independently funded studies showed an effect while most of the industry-funded studies did not. In fact, industry-funded studies had about ten times fewer odds of finding an adverse effect from cell phone use. That’s even worse than the drug industry! Studies sponsored by Big Pharma about their own products only had about four times the odds of favoring the drug compared to independent researchers. Big Tobacco still reigns supreme when it comes to Big Bias, though. Why do research articles on the health effects of second-hand smoke reach different conclusions? Well, it turns out that studies funded by the tobacco industry itself had a whopping 88 times the odds of concluding it was not harmful. So about ten times more for telecom puts it more towards the drug industry end of the bias spectrum.

There are conflicts of interest on both sides of the debate, though. If it’s not financial conflict, then it may be intellectual, as it can be human nature to show bias towards evidence that supports your personal position. As such, you’ll see flimsy science published, like a study I show at 3:55 in my video that appears to find a “disturbing” and “very linear relationship” between the states with the most brain tumors and the states with the most cell phone subscriptions. Okay, but one could think of lots of reasons why states like New York and Texas might have more brain tumors and more cells phones than the Dakotas, and those reasons have nothing to do with cell phone radiation.

Sometimes, you might even see outright fraud with allegations that the academic researchers who authored two of those genotoxicity papers and the very review I mentioned earlier were involved in scientific misconduct—allegations they deny, pointing out that their lead accuser turned out to be a lawyer working for the telecom industry. 

Whenever there’s a trillion-dollar industry involved, whether it’s the food industry, tobacco industry, drug industry, or telecom industry, there’s so much money involved that the science can get manipulated. Take the nuclear energy industry for example. There were decades of “a high-level, institutional…cover up” about the health consequences of Chernobyl. The official estimates of resulting health problems were a hundred or even a thousand times lower than estimates from independent researchers. Did only 4,000 people eventually die from it or nearly a million? It depends on who you ask and who happens to be funding whomever you’re asking. That’s why, when it comes to cancer, all eyes turn to the International Agency for Research on Cancer, the IARC, which is the official World Health Organization body that independently and objectively tries to determine what is and is not carcinogenic. You can find out what the IARC concluded about cell phones in my video Cell Phone Brain Tumor Risk?.


For more on cell phones and Wi-Fi, check out these other videos:

 

I’ve talked a lot about the corrupting influence of commercial interests on science. See, for example:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

Helpful Foods to Support People with Autism

The sulforaphane found in five cents’ worth of broccoli sprouts has been shown to benefit autism in a way no drug ever has in a randomized, double-blind, placebo-controlled study.

You may remember my series of videos, which includes Prevent Cancer from Going on TOR, about target of rapamycin (TOR), the engine-of-aging enzyme. Kids with autism tend to have higher TOR activity in their bodies, and this hyperactive TOR signaling may play a role in causing autism, which makes TOR a potential target to treat autism or even theoretically reverse it if we could target downstream TOR signaling, like between TOR and S6K1, as you can see at 0:29 in my video Best Foods for Autism. In fact, that’s one of the ways sulforaphane, a compound in broccoli and other cruciferous vegetables, kills off prostate cancer cells—by inhibiting the signal transduction between TOR and S6K1. Sulforaphane is also “a potent inhibitor” of breast cancer cells because “it targets downstream elements of the [TOR] pathway.”

So, if broccoli blocks TOR and if we give it to those with autism, maybe it would block some of the synaptic dysfunction that contributes to the features of autism—and that’s in addition to blocking autism pathways four other ways: oxidative stress, lower antioxidant capacity, mitochondrial dysfunction, and brain inflammation. What’s more, this doesn’t only occur in a petri dish. “Importantly, sulforaphane can cross the blood-brain-barrier,” so when you eat broccoli, sulforaphane quickly reaches your brain “to exert its protective effects”—at least it does in theory. You don’t know, of course, until you put it to the test.

You can understand why such a study could attract researchers from such leading institutions as Harvard and Johns Hopkins, and get published in one of our most prestigious journals, the Proceedings of the National Academy of Sciences. What did they find? First, what did they do? “In a placebo-controlled, double-blind, randomized trial, young men (aged 13–27) with moderate to severe ASD [autism] received sulforaphane from broccoli sprouts or an indistinguishable sugar pill. They were dosed according to body weight: Those under 100 pounds got about a tablespoon of broccoli sprouts’ worth of sulforaphane a day, which is about a cup’s worth of broccoli, those weighing between 100 and 200 pounds got about the equivalent of two cups of broccoli or two tablespoons of fresh broccoli sprouts, and those over 200 pounds got three cups’ worth a day or a little under a quarter cup of broccoli sprouts. Why didn’t the researchers use actual broccoli or actual sprouts? If they had, it wouldn’t have been a blinded study. The patients, doctors, and parents would know who was and who wasn’t getting the special treatment, which could introduce bias through the placebo effect. Instead, with this study set-up, no one knew until the end who got the sulforaphane and who got the placebo.

The researchers chose dietary sulforaphane because of its capacity to reverse oxidation, dysfunction, and inflammation, but when put to the test, did it actually work? The placebo didn’t. Give people with autism nothing, and nothing much happens. But effectively secretly sneak them some broccoli, and substantial improvements in behavior, social interaction, and verbal communication occurred. However, it all disappeared once the broccoli was stopped. As you can see at 3:25 in my video, on the Aberrant Behavior Checklist, which includes things such as repetitive behaviors, there was no big change in the placebo group, which is what you’d expect, but the abnormal behaviors plunged in the sulforaphane group—the group who got the sulforaphane found in only about five cents’ worth of broccoli sprouts a day. The study ended in week 18, however, and a month later, things were heading back to where they started.

There were similar findings on a Social Responsiveness Scale: significant improvements were seen until the treatment was stopped, and then the participants went right back to functioning as poorly as those in the placebo group had continued to function. And these weren’t just scores on a page. “The substantial improvements…were conspicuous”—the doctors, parents, and caregivers could see the improvements. No drug has ever been shown to have these kinds of effects. What’s more, these were young men, starting at age 13. One could imagine it working as well or even better with younger children because their brains are still developing. And, is there a downside? “Broccoli sprouts are widely consumed as a food item all over the world by a very large number of individuals, without any reports of adverse effects”—but remember we’re talking about whole foods, not sulforaphane supplements.

Indeed, broccoli sprouts work, but commercial broccoli sprout supplements hardly work at all. As you can see at 4:55 in my video, broccoli has sulforaphane, with the florets more so than the stems, and broccoli sprouts have about ten times more sulforaphane. In comparison, broccoli pills, powders, and supplements have little or none. So, broccoli and other cruciferous vegetables are for all kids, whether they have autism or not, and they may be for pregnant women as well for the potential prenatal prevention of autism in the first place.

This article covers the big finale to my initial three-part video series on autism. For the background that led researchers down this path of clues, check out Fever Benefits for Autism in a Food and Fighting Autism Brain Inflammation with Food. You can also check: Flashback Friday: The Best Foods for Fighting Autism and Brain Inflammation. 

We understand there may be a variety of challenges pertaining to catering to picky palates, sensory and food texture sensitivities, or kids who are reluctant to try new foods, and we hope this evidence-based article can provide some helpful health information to parents and health practitioners. For more tips and tricks, check out How to Get Kids to Eat Their Vegetables.


For more on autism, see:

My video Broccoli: Sprouts vs. Supplements underscores the importance of plants over pills, and Biggest Nutrition Bang for Your Buck tells you how to grow your own.

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations: