The fifth generation of cellular network technology, 5G, promises faster data speeds and greater connectivity. Its rollout has brought renewed public discussion regarding its potential health implications, specifically whether the radiofrequency signals used by 5G can affect the human brain. The current scientific understanding of this technology’s interaction with the body provides the necessary context to address these concerns. This article explores how 5G signals interact with biological tissue, reviews the available research on neurological and cognitive effects, and outlines the official safety positions of global health authorities.
How 5G Radiofrequency Energy Interacts with Biological Tissue
5G technology uses Radiofrequency (RF) Electromagnetic Fields (EMF) to transmit data. This RF-EMF is non-ionizing radiation, unlike high-energy ionizing radiation (like X-rays or gamma rays) which can cause DNA damage. Non-ionizing radiation, emitted by 5G, 4G, and Wi-Fi, has energy levels too low to cause molecular damage.
The primary mechanism by which non-ionizing RF energy interacts with biological tissue is the generation of heat, known as the thermal effect. When the body absorbs this energy, it causes localized heating. This thermal effect forms the basis for most safety regulations worldwide, and the absorption rate is measured by the Specific Absorption Rate (SAR).
5G operates across various frequency bands, including higher bands known as millimeter waves (mmWave), ranging from 24 GHz up to 100 GHz. These higher frequencies penetrate biological tissue far less deeply than the lower frequency bands used by older generations like 4G. At 30 GHz, for example, the penetration depth is approximately one millimeter, meaning the energy is largely absorbed by the skin and superficial tissue layers.
The skin and the surface of the eye are the main tissues exposed to these higher-frequency 5G signals, with minimal energy reaching deeper structures, including the brain. This superficial absorption contrasts with the lower-frequency RF fields of 4G and 3G, which could penetrate more deeply into the head. Consequently, higher 5G frequencies are considered less likely to affect the brain directly than previous cellular technology generations.
Research Findings on Neurological and Cognitive Effects
Scientific inquiry into cellular technology’s effects on the brain focuses on two areas: the risk of brain tumors and non-cancer neurological symptoms. Large-scale epidemiological studies tracking cellular phone use have generally not established a link between radiofrequency exposure and an increased incidence of brain cancers, such as gliomas or acoustic neuromas. For instance, a long-term study involving over 776,000 women found no statistically significant association between cellular phone use and the risk of developing most brain tumors.
The International Agency for Research on Cancer (IARC) classified RF-EMF as “possibly carcinogenic to humans” (Group 2B). This classification is based on limited evidence from human and animal studies, not a definitive causal link. Furthermore, the superficial nature of higher-frequency 5G signals suggests that any potential risk would shift from the deeply located brain to the skin, though current evidence does not confirm this.
Regarding non-cancer neurological complaints, such as headaches, dizziness, or perceived cognitive decline, research remains largely inconclusive in establishing a causal link to RF exposure. Human experimental studies using controlled exposure to 5G-relevant frequencies (around 3.5 GHz) have generally shown non-significant changes in the electrical activity of the brain (EEG) in healthy young adults.
One recent study suggested that exposure to a 3.6 GHz 5G frequency before sleep was linked to changes in brain wave activity during the non-rapid eye movement phase, but this effect was only observed in individuals with a specific genetic variation. The authors noted that exposure levels were within international safety limits. Currently, there is insufficient evidence to consistently link typical exposure levels from cellular technology to adverse cognitive or neurological symptoms.
Official Safety Guidelines and Global Health Authority Stance
The safety of 5G and all wireless technologies is overseen by major international and national regulatory bodies. The World Health Organization (WHO) and the International Commission on Non-Ionizing Radiation Protection (ICNIRP) are two of the most influential entities setting global exposure standards.
ICNIRP establishes exposure limits based on preventing the scientifically confirmed adverse health effect of RF energy: the thermal effect. Their guidelines ensure that exposure levels are low enough to prevent substantial heating of human tissue. The organization updated its guidelines in 2020 to specifically address higher frequencies, including those used by 5G, by introducing detailed restrictions for exposures above 6 GHz.
Both the WHO and ICNIRP maintain that, based on a thorough review of the scientific literature, there is no conclusive evidence that RF-EMF exposure from wireless technologies, including 5G, causes adverse health effects when exposure remains below established international guidelines. These guidelines cover the entire radiofrequency range used by 5G and future technologies.
These bodies acknowledge the public interest and the need for ongoing research, especially since 5G deployment is relatively new and involves higher frequencies. However, they consistently state that current exposure levels from 5G infrastructure are typically a small fraction of the maximum limits set by the guidelines, providing a large margin of safety against known biological effects.