Effects of 3.5 GHz (5G) Radiofrequency Radiation on Ghrelin, Nesfatin-1, and Irisin Levels in Diabetic and Healthy Brains
Bektas H, Algul S, Altindag F, Yegin K, Akdag Z, Dasdag S · 2022
At a Glance
Of the 874 peer-reviewed studies in this collection on electromagnetic fields, 701 — 80.2% — reported biological effects. On children's brains specifically the direct evidence is thin and the honest summary is layered: tissue measurements show absorption properties change with age, animal work shows radiofrequency exposure producing DNA strand breaks in brain cells, one large birth cohort links prenatal phone exposure to behavioral difficulties while cautioning the link may be non-causal, and the largest brain-tumor study found no overall increase in risk.
Based on analysis of 903 peer-reviewed studies
Children's brains are fundamentally different from adult brains—not just smaller, but actively developing, forming new neural connections, and undergoing critical periods of growth. This raises important questions about how electromagnetic field exposure might affect the developing brain.
Researchers have approached this question through multiple methods: measuring how much RF energy children's brains absorb compared to adults, studying cognitive outcomes in children with various EMF exposures, and examining brain tissue effects in laboratory settings.
This page presents the scientific evidence on EMF exposure and childhood brain development.
Key Findings
- -701 of 874 studies (80.2%) in this collection found biological effects from electromagnetic field exposure
- -Radiofrequency exposure produced single- and double-strand DNA breaks in rat brain cells at a whole-body absorption rate of 1.2 W/kg, from both pulsed and continuous-wave radiation (Lai and Singh 1996)
- -Tissue dielectric properties decrease with age, most markedly in brain and skull, which is the measured basis for expecting different absorption in children (Peyman 2001)
- -Prenatal phone exposure was associated with emotional and hyperactivity problems at age seven across 13,159 children, an association the authors warn may be non-causal (Divan 2008)
- -The largest brain-tumor study found no overall increased risk — 2,708 glioma and 2,409 meningioma cases across 13 countries — with suggestions of elevated glioma risk at the highest exposures that bias prevents interpreting causally (INTERPHONE 2010)
What the Research Shows
What the Research Shows
Of the 874 peer-reviewed studies indexed here on electromagnetic fields, 701 — 80.2% — reported measurable biological effects. Very few examine children's brains directly. Children cannot be enrolled in controlled radiofrequency exposure experiments, so the evidence comes from animal brain tissue, tissue-property measurement, adult cognitive testing, and observational cohorts.
How Absorption Changes With Age
Peyman and colleagues (2001) measured the dielectric properties of ten rat tissues at six ages across 130 MHz to 10 GHz. Properties decreased with age, and the trend was most apparent in brain, skull and skin, driven by declining water content. Because those properties govern how radiofrequency energy enters and deposits in tissue, younger tissue interacts with these fields differently. This is the measured basis for treating children's exposure as a distinct question — tissue data from animals, not a measured dose to a child's brain.
What Exposure Does to Brain Cells
Lai and Singh (1996) exposed rats at a spatial-averaged power density of 2 mW/cm², producing a whole-body specific absorption rate of 1.2 W/kg, and measured DNA strand breaks in individual brain cells four hours after exposure. Both single- and double-strand breaks increased, with no significant difference between pulsed and continuous-wave radiation. The authors positioned it as support for earlier in vitro and in vivo work showing radiofrequency effects on DNA.
A developing brain is building the structure it will use for life, and DNA damage during that period carries different consequences than the same damage in a mature, slowly dividing tissue. That reasoning is why the animal result gets weighted heavily in discussions of children — it is an inference about vulnerability, not a measured pediatric outcome.
Cognition and Behavior
Preece and colleagues (1999) tested 36 adults under about 1 W mean power at 915 MHz in a randomized cross-over design. Only choice reaction time changed, and it improved. Word, number and picture recall and spatial memory were unaffected.
The behavioral signal in children comes from Divan and colleagues (2008), who followed 13,159 children in the Danish National Birth Cohort to age seven. Children with possible prenatal or postnatal phone exposure showed greater odds of behavioral problems — emotional and hyperactivity difficulties — with the prenatal association stronger and surviving adjustment for confounders. The authors state that the associations may be non-causal and may reflect unmeasured confounding.
Hutter and colleagues (2006) added population evidence in adults, finding effects on wellbeing and cognitive performance among 365 residents near base stations at exposures far below recommended limits, with no known mechanism at those levels.
The Strongest Counter-Evidence
The INTERPHONE study ran an interview-based case-control study across 13 countries with 2,708 glioma and 2,409 meningioma cases and matched controls. It found no overall increase in either tumor type among mobile phone users — in fact reduced odds ratios that its authors attributed to participation bias or other methodological limitations. Suggestions of increased glioma risk appeared at the highest exposure levels, but the authors concluded that bias and error prevent a causal interpretation. That study concerns adults and tumors, not children and development, and it is the most substantial null result in this area.
What This Does Not Establish
Nothing here demonstrates that phone or WiFi exposure impairs a child's brain development. The tissue and DNA work is animal-based at exposures above typical use. The cognitive findings are in adults and are not uniformly negative. The behavioral cohort measures recalled phone use and carries the confounding its authors name.
Reasonable Practice
The steps that follow from this evidence are the ones that would be sensible even if every study above were overturned: keep phones away from children's heads by using speaker mode or wired headphones, favor texting over calling, keep devices out of bedrooms overnight, and use wired connections where devices do not move. Each reduces exposure during the years when the tissue differences are largest, and none costs anything worth counting.
Related Studies (903)
Comparison of ELF-EMFs stimulation with current stimulation on the regulation of LTP of SC-CA1 synapses in young rat hippocampus
Unknown authors · 2021
Both ELF-EMFs and microampere currents significantly reduced long-term potentiation. The effect of 0.1 μA current was similar to 100 Hz/2 mT ELF-EMFs, while 0.2 μA current had a stronger effect than 200 Hz/2 mT ELF-EMFs on high-frequency stimulation LTP.
No Significant Effects of Cellphone Electromagnetic Radiation on Mice Memory or Anxiety: Some Mixed Effects on Traumatic Brain Injured Mice
Unknown authors · 2021
The study examined the effects of cellular radiation on male and female mice, assessing anxiety, spatial memory, and general well-being. Radiation alone did not significantly change anxiety levels or spatial/visual memory. In mice with mild traumatic brain injury, radiation improved visual memory in both sexes but worsened spatial memory in females.
Repeated electromagnetic field stimulation lowers amyloid-β peptide levels in primary human mixed brain tissue cultures
Unknown authors · 2021
Researchers exposed primary human brain cultures at day 7 to 64 MHz electromagnetic fields for one hour daily over 14 days. This treatment significantly lowered secreted Aβ40 and Aβ42 peptide levels compared to untreated cultures. Similar reductions were also observed with one or two hours of daily exposure over 14 days, and with 4 or 8 days of exposure in cultures at a later stage. The minimum specific absorption rate needed for a biological effect was 0.4 W/kg. Exposure did not cause cellular toxicity or change sAPPα levels, indicating the Aβ reduction was not due to a shift to the α-secretase pathway.
Association between estimated whole-brain radiofrequency electromagnetic fields dose and cognitive function in preadolescents and adolescents
Unknown authors · 2021
Researchers conducted a cross-sectional analysis of preadolescents aged 9-11 years and adolescents aged 17-18 years from the Dutch ABCD study (n=1664 preadolescents) and the Spanish INMA project (n=1288 preadolescents and n=261 adolescents). Overall whole-brain RF-EMF doses were estimated from mobile and DECT phone calls, other mobile phone uses, tablet use, laptop use, and far-field sources. Higher overall doses from all sources and from phone calls were associated with lower non-verbal intelligence in Dutch and Spanish preadolescents (-0.10 points per 100 mJ/kg/day increase, 95% CI -0.19 to -0.02), but no doses were related to any other cognitive outcome in Spanish preadolescents or adolescents.
Brain & Nervous SystemNo Effects Found
Effects of 2.45 GHz Wi-Fi exposure on sleep-dependent memory consolidation
Unknown authors · 2021
Thirty young men participated in a double-blind, sham-controlled crossover study with all-night 2.45 GHz Wi-Fi exposure. Declarative memory improved overnight with Wi-Fi exposure, but emotional and procedural memory were unaffected. No sleep-specific physiological parameters changed with exposure, so the behavioral effect lacked physiological support and may be a random finding.
Electromagnetic Waves from Mobile Phones may Affect Rat Brain During Development
Unknown authors · 2021
During operation, mobile phones emit energy in the form of electromagnetic fields that can be absorbed by the user's head. Researchers studied the influence of mobile phone exposure on nervous response by analyzing electrophysiological measurements of brain wave activity. EEG test measurements were taken when the participant was not using and when using a mobile phone.
Estimated whole-brain and lobe-specific radiofrequency electromagnetic fields doses and brain volumes in preadolescents
Estimated whole-brain and lobe-specific radiofrequency electromagnetic fields doses and brain volumes in preadolescents Alba Cabré-Riera et al. · 2020
The study analyzed 2,592 preadolescents aged 9 to 12 years from the Generation R Study in Rotterdam, Netherlands. An integrated exposure model estimated whole-brain and lobe-specific radiofrequency electromagnetic field doses from sources such as phone calls, tablet use, laptop use, and far-field sources. The estimated overall whole-brain dose was 84.3 millijoules per kilogram per day, with the highest lobe-specific dose in the temporal lobe at 307.1 millijoules per kilogram per day. Overall doses from all sources, phone calls, and far-field sources were not associated with global, cortical, or subcortical brain volumes. However, higher whole-brain dose from mobile phone internet use, texting, tablet use, and wireless laptop use was associated with a smaller caudate volume.
The effect of short-term electromagnetic fields caused by mobile phones on the electrical activity of alpha and beta brain waves
Unknown authors · 2020
Testing of behavioral and cognitive development in rats after prenatal exposure to 1800 and 2400 MHz radiofrequency fields
Unknown authors · 2020
Pregnant rats were exposed to radiofrequency fields starting on day 21 of pregnancy, and offspring were tested with Y maze at 3 weeks, open field at 7 weeks, and hippocampal NMDAR expression at 9 weeks. The 1800 MHz and 1800 MHz + WiFi groups showed a downward trend in body weight, and the WiFi group opened eyes earlier than controls. In open field tests, the 1800 MHz + WiFi group had shorter overall path length and delayed stationary time, the WiFi group had shorter path length and increased velocity in the error arm, and the 1800 MHz + WiFi group showed increased central area activity. Both exposure groups down-regulated NR2A and NR2B and up-regulated NR2D, NR3A, and NR3B, while the WiFi group also up-regulated NR1 and NR2C.
Trace elements homeostasis in brain exposed to 900 MHz RFW emitted from a BTS-antenna model and the protective role of vitamin E
Azimzadeh M, Jelodar G · 2020
The study examined the effects of 900 MHz RFW on brain iron, copper, zinc, and manganese concentrations and the protective role of vitamin E. Twenty adult male Sprague-Dawley rats were divided into four groups: control, vitamin E only, vitamin E plus RFW exposure, and RFW exposure only. The rats were exposed to RFW for 30 consecutive days at 4 hours per day while freely moving in the cage. Brain tissue levels of the elements were measured on the last day using atomic absorption spectrophotometry. Exposure significantly increased iron, copper, manganese, and the copper-to-zinc ratio while decreasing zinc, and vitamin E pre-treatment improved iron, copper, manganese, and the ratio but not zinc.
Risk to pollinators from anthropogenic electro-magnetic radiation (EMR): Evidence and knowledge gaps
Vanbergen AJ et al. · 2019
The authors assessed whether artificial light at night and radiofrequency electromagnetic radiation from wireless technologies and power lines threaten pollinators. They found that knowledge of the risk is inconclusive, unresolved, or only partly established because of a lack of high-quality studies. Some studies show artificial light at night can alter pollinator communities, pollination, and fruit set. Laboratory experiments show honey bees and other invertebrates can detect electromagnetic radiation, but do not show it affects insect behavior in ecosystems. Robust evidence of radiofrequency radiation impacts on pollinator abundance or diversity is limited to a single study with mixed results.
(2019): Higher exposure to cell tower RFR was associated with delayed fine and gross motor skills, spatial working memory, and attention among adolescents compared to students exposed to lower levels of cell tower RFR
Meo et al · 2019
Human exposure to radio-frequency radiation has grown more than 100,000-fold since World War II. In 2011, IARC classified RFR as a possible human carcinogen. Three large-scale rodent studies found significantly increased rates of Schwannomas, malignant gliomas, and chromosomal DNA damage from RFR exposures mimicking lifetime human exposures. Compared with an adult male, a cell phone held against a child's head exposes deeper brain structures to greater radiation doses per unit volume, and the child's skull bone marrow absorbs a roughly 10-fold higher local dose. Recent reports suggest that men who keep cell phones in their trouser pockets have significantly lower sperm counts and significantly impaired sperm motility and morphology, including mitochondrial DNA damage.
Low-Field Magnetic Stimulation Restores Cognitive and Motor Functions in the Mouse Model of Repeated Traumatic Brain Injury: Role of Cellular Prion Protein
Unknown authors · 2019
Researchers induced traumatic brain injury in mice using a weight-drop method once daily for three days. Low-field magnetic stimulation was applied for 20 minutes once daily for four days immediately after each injury. Mice receiving the stimulation showed significant improvement in cognitive and motor tests including open field exploration, rotarod, and novel location recognition. The treatment increased cellular prion protein and decreased glial fibrillary acidic protein in cortical and hippocampal regions, and increased neuronal nuclei in the cortex. Proteins related to circadian rhythm decreased in stimulated mice compared with sham-treated mice.
Effect of Static Magnetic Field of Electric Vehicles on Driving Performance and on Neuro-Psychological Cognitive Functions
Unknown authors · 2019
Researchers used a lane change task and reaction time tests to assess driving performance and cognitive functions in 17 students exposed to a 350 μT static magnetic field. EEG recordings were taken during the experiment to monitor brain activity related to performance and cognition. The results showed that the static magnetic field did not considerably affect driving performance or cognitive functions, but a correlation was found between the EEG beta sub-band and reaction time.
Melatonin Modulates NMDA-Receptor 2B/Calpain-1/Caspase-12 Pathways in Rat Brain After Long Time Exposure to GSM Radiation
Unknown authors · 2019
Researchers divided 24 male Wistar albino rats into four groups and exposed one group to 2100 MHz radiation for 30 minutes over a 90-day experiment. Subcutaneous melatonin was injected into a third group and given 40 minutes before radiation to a fourth group. Radiation caused neuronal edema, fewer neurons in hippocampal CA1 and CA3, Purkinje neuron displacement, and dark neurons. Radiation activated the NMDA-receptor 2B/Calpain-1/Caspase-12 pathway, and melatonin did not demonstrate protective effects.
Changes in pyramidal and granular neuron numbers in the rat hippocampus 7 days after exposure to a continuous 900-MHz electromagnetic field during early and mid-adolescence
Unknown authors · 2019
Three-week-old male Sprague Dawley rats were divided into control, pseudo-exposed, and EMF groups, with the EMF group receiving a 900-MHz EMF for 1 hour per day for 25 days. Following exposure, behavioral tests were performed for seven days before the animals were euthanized and their brains removed. Brain sections were stained with toluidine blue and pyramidal neuron numbers in CA1, CA2-3, and hilus and granule neuron numbers in the dentate gyrus were estimated using optical fractionation. The EMF group showed statistically higher numbers of both pyramidal and granule neurons than the pseudo-exposed group, and histopathological examination revealed cytoplasmic disruption in those neurons.
Brain & Nervous SystemNo Effects Found
Uncertainty Analysis of Mobile Phone Use and Its Effect on Cognitive Function: The Application of Monte Carlo Simulation in a Cohort of Australian Primary School Children
Unknown authors · 2019
The study applied Monte Carlo simulation to data from the ExPOSURE study of 412 Australian primary school children. Multiple linear regression models found weak evidence of an association between mobile phone calls and cognitive function. Associations were observed for Go/No Go, Groton maze learning, and Stroop time ratio tasks. When uncertainty analysis was introduced, the results shifted closer to the null hypothesis.
Transduction of the Geomagnetic Field as Evidenced from alpha-Band Activity in the Human Brain.
Wang CX et al. · 2019
Effects of single- and hybrid-frequency extremely low-frequency electromagnetic field stimulations on long-term potentiation in the hippocampal Schaffer collateral pathway.
Zheng Y, Ma XX, Dong L, Gao Y, Tian L. · 2019
Researchers applied single- and hybrid-frequency magnetic fields with an intensity of 1 mT to rat hippocampal slices in vitro to study effects on long-term potentiation (LTP) in synaptic plasticity. The amplitude of fEPSPs decreased significantly under both single- and hybrid-frequency magnetic stimulation. The 15-Hz single-frequency stimulation showed the most significant regulatory effect, but mixing it with higher frequencies significantly weakened that effect. The regulating effect among four different hybrid-frequency ELF-EMF stimulations on LTP showed no significant differences.
A comparative study on influences of static electric field and power frequency electric field on cognition in mice.
Di G, Kim H, Xu Y, Kim J, Gu X. · 2019
Researchers exposed mice to a static electric field (SEF) and a power frequency electric field (PFEF), each at 35 kV/m, for 49 days. The study found that a 35 kV/m SEF did not cause significant influences on learning and memory ability in mice, while a 35 kV/m PFEF caused significant positive effects on learning and memory ability on day 33. Behaviors were assessed using the Morris water maze test, and amino acid neurotransmitter levels in the hippocampus were examined during exposure.
Effect of 900-, 1800-, and 2100-MHz radiofrequency radiation on DNA and oxidative stress in brain
Alkis ME et al. · 2019
Researchers exposed male Sprague Dawley rats to radiofrequency radiation at 900, 1800, or 2100 MHz for 2 hours per day for 6 months to study DNA damage and oxidative stress in blood and brain tissue. DNA damage and oxidative stress indicators were found higher in the radiofrequency radiation exposure groups than in the sham-control group. The researchers concluded that 900-, 1800-, and 2100-MHz radiofrequency radiation may cause oxidative damage, induce an increase in lipid peroxidation, and increase oxidative DNA damage in the frontal lobe of rat brain tissues, and that 2100-MHz radiation may cause formation of DNA single-strand breaks.
National data showed that delayed sleep in six-year-old children was associated with excessive use of electronic devices at 12 years
Kato T, Yorifuii T, Yamakawa M, Inoue S · 2018
Researchers analyzed 9607 adolescents who owned mobile phones in 2013 using a Japanese longitudinal survey that began in 2001. The study examined delayed bedtime at age six and excessive use of mobile phones, television, and video games at age twelve. Delayed bedtime at age six was associated with excessive texting at weekends, with adjusted odds ratios of 1.88 for the 10–11 pm group and 1.98 for the after 11 pm group compared to the before 9 pm group. Later bedtimes were also associated with increased risks of excessive television viewing and video game use.
A prospective cohort study of adolescents' memory performance and individual brain dose of microwave radiation from wireless communication
Foerster et al · 2018
Researchers modeled RF-EMF brain dose for each participant and tracked verbal and figural memory score changes over one year using multivariable linear regression. Higher cumulative RF-EMF brain dose was associated with decreased figural memory scores in the whole sample and more strongly in right-side phone users. Media use unrelated to RF-EMF showed no significant associations with memory changes.
Whole-body pulsed EMF stimulation improves cognitive and psychomotor activity in senescent rats
Unknown authors · 2018
Psychomotility was assessed in an open field, attention in novel object recognition, and spatial learning in the Morris water maze. EMF stimulation increased vertical rearing activity in the open field, improved attention-based discrimination in novel object recognition, and facilitated working memory spatial learning in the water maze. No undesirable side effects were observed even at the highest dose.
What This Means for You
- Children's developing brains may be more susceptible to EMF effects than adult brains.
- Limit screen time and device use, especially for younger children.
- Use speakerphone or wired headphones instead of holding phones to children's heads.
- Shield your child's phone with a radiation-deflecting pouch. SYB Phone Pouch
Further Reading:
Frequently Asked Questions
No study in this collection measured electromagnetic exposure against children's brain development directly. The supporting evidence is indirect: radiofrequency exposure produced DNA strand breaks in rat brain cells (Lai and Singh 1996), absorption-governing tissue properties differ with age (Peyman 2001), and prenatal phone exposure was associated with behavioral difficulties at age seven in a 13,159-child cohort whose authors caution the link may be non-causal (Divan 2008).
The physical basis is real but narrower than usually stated. Dielectric properties governing radiofrequency absorption decrease with age, most markedly in brain and skull tissue, because water content falls (Peyman 2001). That means young tissue interacts with these fields differently. Combined with a developing nervous system's smaller margin for error in repair, it is a reasonable basis for extra caution — not a measured multiplier for a child's absorbed dose.
No. The largest study of mobile phones and brain tumors, INTERPHONE, examined 2,708 glioma and 2,409 meningioma cases across 13 countries in adults and found no overall increase in risk, with suggestions at the highest exposure levels that its authors said bias and error prevent interpreting causally (INTERPHONE 2010). This collection contains no comparable pediatric tumor study.
Use the measures that reduce exposure at no cost: speaker mode or wired headphones instead of the phone at the ear, texting instead of calling where it makes no difference, devices out of bedrooms overnight, and wired connections for anything that stays put. These are worth doing on the strength of the evidence as it stands, and they remain sensible whichever way the science resolves.
Further Reading
For a comprehensive exploration of EMF health effects and practical protection strategies, explore these books by R Blank and Dr. Martin Blank.
