Does Your Phone’s Radiation Harm You? What the Science Says

Should you be worried about sleeping with your phone beside your head? What about keeping it in your pocket? Can 5G cause cancer? Does Wi-Fi damage the body?

Many of us have asked these questions, and honestly, it is not difficult to understand why. Almost everywhere you turn, someone is warning you about phone radiation, whether it is a forwarded WhatsApp message from a concerned relative or an elder’s warning passed down as common sense. Some of these claims contain a little bit of truth. Some are exaggerations, while some are simply myths. So, what does the science actually say? Let’s talk about it without the fearmongering.

First, what exactly is phone radiation?

The word radiation sounds scary because we usually associate it with things like X-rays, nuclear accidents and cancer, but radiation is a much broader term. Sunlight is radiation; heat is associated with electromagnetic radiation, and radio and television signals are radiation too. The important question is what kind of radiation we are talking about. Mobile phones use radiofrequency electromagnetic fields (RF-EMF), a form of non-ionising radiation. That is very different from ionising radiation such as X-rays and gamma rays, which carry enough energy to damage DNA directly. The radiofrequency radiation from mobile phones does not have that kind of energy. That does not mean we should automatically declare it a hundred percent harmless; it means we need to study it based on what it actually does, rather than simply reacting to the word radiation.

So, Does Your Phone Cause Cancer?

This is probably the biggest concern, and the latest research is reassuring. A major WHO-commissioned systematic review published in 2024 examined 63 studies from 22 countries, looking at mobile-phone RF exposure and cancers of the brain and nervous system.

The researchers found no association between mobile-phone use and glioma, meningioma, acoustic neuroma, pituitary tumours or salivary-gland tumours, and no evidence that the risk increased with longer duration of use, cumulative call time or number of calls. They concluded there was moderate-certainty evidence that mobile-phone exposure to the head likely does not increase the risk of several major brain and head tumours.

A second WHO-commissioned systematic review published in 2025 looked at other cancers, including leukaemia, non-Hodgkin lymphoma and thyroid cancer. Again, the researchers found no association with mobile-phone use, including among people who had used mobile phones for ten years or more. This does not mean scientists have proven that phones can never contribute to cancer; science rarely works in such absolute terms. But the evidence we have today does not support the claim that normal mobile-phone use causes cancer. The National Cancer Institute similarly states that the evidence to date suggests cell-phone use does not cause brain or other cancers in humans.

But wasn’t phone radiation classified as “Possibly Carcinogenic”?

Yes, and this is where a lot of confusion comes from. In 2011, the International Agency for Research on Cancer classified radiofrequency electromagnetic fields as Group 2B, possibly carcinogenic to humans. That classification is often presented online as WHO says phones cause cancer, but that is not what it means. Possibly carcinogenic means there was limited evidence and enough uncertainty that a cancer risk could not be completely ruled out. It does not mean that phones were proven to cause cancer.

Since that classification, considerably more research has been published, and the newer WHO-commissioned reviews have not found an increased cancer risk from ordinary mobile-phone exposure. That distinction matters.

What about sleeping with your phone beside your head?

This is one of those situations where the advice can be sensible even when the reason given online is wrong. There is no convincing evidence that sleeping beside your phone causes brain damage. The WHO says there is no consistent evidence of adverse effects on sleep from RF exposure, and a 2024 systematic review of experimental studies found no significant effect of RF exposure on sleep disturbances.

But there are other reasons not to sleep with your phone under your pillow: the notifications, the temptation to check social media, the late-night scrolling, the bright screen, and the interruption of your sleep. Practically speaking, you also should not put an electronic device under your pillow or blanket while it is charging, because of heat and fire risks. So if you prefer to keep your phone across the room at night, that is a good habit. Just do not tell yourself that you are doing it because your phone is radiating your brain with cancer. There isn’t good evidence for that claim.

What about keeping your phone in your pocket?

This is where the answer becomes more nuanced. There has been concern that RF exposure could affect male fertility, particularly sperm quality, and researchers have actually looked at this question quite seriously.

A 2024 WHO-commissioned systematic review examined human studies involving mobile-phone RF exposure and male fertility, looking at sperm concentration, morphology, motility and total sperm count. Only nine relevant human observational studies were included, and their conclusion was that the evidence is very uncertain.

The studies had important problems, including inaccurate measurement of exposure, small numbers of studies and potential bias, so the researchers said the current evidence was too uncertain to determine whether mobile-phone RF exposure affects male fertility.

This means two extreme claims are both inappropriate. We cannot say your phone definitely causes infertility, but we also cannot confidently say that scientists have completely ruled out any effect on sperm. There is still a question worth researching. There is also laboratory and animal research suggesting possible effects on sperm under some exposure conditions, but many of those experiments used exposure levels different from typical human exposure.

So if you are trying to conceive, is there anything wrong with keeping your phone out of your trouser pocket when practical? Not really; you can put it in a bag or somewhere else, but that is a precaution, not evidence that your phone is making you infertile.

What about women and pregnancy?

This is another area where people understandably worry. A 2024 systematic review examined RF exposure and pregnancy outcomes, including miscarriage, preterm birth, low birth weight, small-for-gestational-age babies and congenital abnormalities. The researchers found that the available evidence was very uncertain, mainly because of limitations and potential bias in the studies, and concluded that better-designed research is needed before firm conclusions can be made.

So again, we should not turn uncertainty into fear. There is currently no good evidence that ordinary phone use causes birth defects or miscarriage, but because the evidence for some pregnancy outcomes is limited, continuing to study the question is reasonable.

And then there is 5G

Few technologies have generated as much fear as 5G. You will see claims that it uses dangerous radiation, damages DNA, causes cancer or even causes infertility. Let’s separate fact from fiction. Five G does use radiofrequency electromagnetic energy, and some 5G technologies operate at higher frequencies than older mobile networks, but higher frequency does not automatically mean ionising or cancer-causing radiation.

5G remains within the non-ionising portion of the electromagnetic spectrum. The National Cancer Institute notes that 5G can use frequencies extending much higher than older generations, but these frequencies are still non-ionising. At sufficiently high RF exposure, the established effect is heating, which is why exposure limits exist, but normal public exposure from wireless technologies is designed to remain below levels that produce significant heating.

The WHO notes that exposures from wireless networks are generally low and that no consistent evidence of harmful health effects has been established at typical public exposure levels. So yes, 5G is higher frequency than some older mobile technologies, but no, that does not make it equivalent to X-rays, and no, it has not been proven to cause cancer or infertility.

What about Wi-Fi?

Your Wi-Fi router also produces RF radiation, but here is something people often forget: distance matters. A router might be several metres away from you, while your phone can be pressed directly against your head during a call, and RF exposure generally decreases rapidly as you move away from the source. So someone might spend hours holding a phone against their head while worrying about the tiny amount of RF energy coming from the router across the room, which does not make much sense from an exposure perspective. The WHO says exposures from wireless networks are generally very low and that studies have not established adverse health effects from the low-level exposures associated with wireless networks. You do not need to sleep in a Faraday cage because you have Wi-Fi.

What about Headaches, Dizziness and “Electromagnetic Sensitivity”?

Some people genuinely report headaches, fatigue, dizziness, sleep problems and other symptoms that they associate with electromagnetic fields. We should not mock people for experiencing symptoms; the symptoms can be very real. The question is whether RF exposure is causing them.

A 2024 systematic review of controlled human experiments included 41 studies involving 2,874 participants, and the researchers found no significant effect of RF exposure on headache, sleep disturbance or general symptoms. Participants generally could not tell whether they were actually being exposed better than would be expected by chance.

Another 2024 systematic review found that short-term RF exposure did not reduce cognitive performance in human experimental studies. That does not mean someone’s headache is not real; it means the evidence does not support RF exposure as the cause.

So, should we simply ignore Phone Radiation?

I would not, but I also would not be afraid of my phone. There is a sensible middle ground. If you want to reduce your RF exposure, you can use speakerphone for long calls, use earphones when convenient, avoid keeping your phone pressed against your body unnecessarily, and put some distance between your phone and your head when you are not actively using it.

If you want very low RF exposure while sleeping, use airplane mode and disable wireless connections, avoid unnecessarily long calls when your phone has a very weak signal since phones may increase their transmission power when connecting to a network, and do not put a phone under your pillow while it is charging. None of these habits requires panic. They are simply easy precautions.

The bigger problem may not be Radiation at all

This is the part I find particularly interesting. We spend hours looking at these devices, lose sleep because of them, become distracted while driving, sit for long periods, and scroll when we should be sleeping. We check notifications hundreds of times, and we sometimes become so attached to our phones that a few minutes without one feels uncomfortable. Those are very real issues.

The National Cancer Institute notes that distracted driving is one of the most consistent health risks associated with cell-phone use. So while we are busy asking whether our phone’s radiation is killing us, we sometimes ignore the much more obvious question: what is our phone use doing to our sleep, attention, relationships and daily life?

The Honest Answer

Here is where I land after looking at the latest evidence. Phone radiation is real, but radiation does not automatically mean danger. The RF radiation produced by mobile phones and Wi-Fi is non-ionising; it does not have enough energy to damage DNA in the same way that X-rays can. The latest large systematic reviews have found no convincing evidence that normal mobile-phone RF exposure causes brain cancer or several other cancers.

The evidence regarding male fertility is more uncertain, but it has not established that mobile phones cause infertility, and the evidence regarding pregnancy outcomes is also uncertain rather than clearly showing harm. Current evidence does not establish that ordinary Wi-Fi or 5G exposure causes cancer, brain damage or other major diseases.

But science should also be humble. Mobile phones have not been part of human life for centuries. Research continues, and scientists remain interested in very long-term exposure and possible effects that may be difficult to detect. So I would not tell you there is absolutely nothing to worry about, and I would not tell you your phone is slowly poisoning you. Both statements go beyond the evidence.

The better answer is much less dramatic: use your phone, enjoy your technology, but use it sensibly. Keep it away from your pillow if that helps you sleep. Use speakerphone when you are on a very long call. Do not keep it unnecessarily pressed against your body. And perhaps most importantly, do not let fear of invisible radiation distract you from the very visible ways your phone can affect your health and your life.

The goal is not to live without technology. The goal is to understand it well enough that technology serves us, not the other way around.

This article is for general information and is not a substitute for medical advice.

Sources

• World Health Organisation, WHO-commissioned systematic reviews on RF-EMF health effects
• National Cancer Institute, Cell Phones and Cancer Risk
• U.S. FDA, Radio Frequency Radiation and Cell Phones
• 2024 systematic review of RF exposure and male fertility
• 2024 systematic review of RF exposure and female reproductive outcomes
• 2024 systematic review of RF exposure and human symptoms
• 2024 systematic review of RF exposure and cognitive performance