What is the difference between ionising and non-ionising radiation in the body?

Ionising radiation — X-rays, gamma rays — carries enough energy per photon to eject electrons from atoms, which can break chemical bonds and damage DNA. Non-ionising radiation — radio waves, Wi-Fi, infrared, visible light — does not carry enough energy per photon to ionise atoms. ICNIRP limits for non-ionising radiation are thermal: they cap tissue heating, not ionisation. The two categories have different biological endpoints and different limit systems.

How does the body's own electric field compare to external household fields?

The electric field across a cell membrane at rest is on the order of 10 million V/m. External power-frequency fields from household wiring are typically 1–100 V/m at normal distances. The ICNIRP reference level for public exposure to power-frequency fields is 200 V/m. The body's internal electric infrastructure operates at fields many orders of magnitude larger than any typical ambient exposure.

What are biophotons and what do they mean for health?

Living cells emit very low levels of coherent light — roughly 10 to 1,000 photons per second per square centimetre — measurable with photomultiplier tubes. This was documented by Professor Fritz-Albert Popp and colleagues at the International Institute of Biophysics. The emission correlates with cell division and metabolic state. Whether biophoton emission serves a regulatory signalling function or is an incidental by-product of metabolism is not yet resolved; the measurement is established, the functional interpretation is an active research question.

Are the subtle energy fields described in traditions like TCM and Ayurveda the same as the electromagnetic fields measured in the clinic?

No — and it matters to hold that distinction. The electric, magnetic, and photochemical fields described in biomedical physics are measurable with standard instruments and governed by published limits. Qi, prana, and related concepts from traditional systems use a different vocabulary and a different evidence standard; they describe patterns of health and dysfunction that these traditions found clinically useful, but which do not map directly onto measurable electromagnetic parameters. Whether the two frameworks will eventually converge is genuinely unknown. Treating them as identical, or as mutually exclusive, both misrepresent the current state of knowledge.

Health Physics: The Role of Energy in Our Body

I am a medical physicist. Most of my working week is spent managing ionising radiation — X-rays, gamma sources, fluoroscopy. The discipline that governs that work is called health physics, and for most of its history it has meant keeping doses within safe bounds for patients and staff — an accurate description, but a much narrower one than the physics of the body actually deserves.

The same physical forces we measure so carefully in the clinic — electric fields, magnetic fields, electromagnetic radiation, mechanical load, and light — are present in every cell of the body, operating continuously, long before any hospital equipment enters the picture. Every nerve that fires, every heartbeat, every moment you reach for a cup and your bones register the load, every second your eyes translate sunlight into time-of-day for your brain — that is physics in the body. Health physics, in its fuller sense, is what happens when you turn the same measurement discipline outward from radiation safety and ask what else is actually going on.

This article is an invitation into that wider view.

Six forces that run through the body

Before anything gets measured, it helps to name what is there. The body sits inside a set of overlapping physical fields: electric, magnetic, gravitational, electromagnetic, and light. To these five I want to add a sixth layer that today’s instruments cannot yet pin down, but that traditional medical systems have mapped carefully for centuries and that runs through almost every tradition of alternative health. We keep it separate from the first five only because physics has no bench for it yet — not because it is not there.

Electric fields — drive nerve signals, heartbeat rhythms, and ion flows across every cell membrane.
Magnetic fields — emerge from the brain and heart, and live inside the much larger magnetic field of the Earth itself.
Gravitational and mechanical forces — continuous, pervasive, and read by the body through bone, muscle, and the inner ear.
Electromagnetic radiation (non-visible) — radio, microwave, infrared; interacts with tissue differently from visible light, and very differently from X-rays.
Light — the visible spectrum, regulating sleep, hormones, mood, and vitamin D synthesis, with attributes that arguably reach beyond what we can currently measure.
Subtle or traditional fields — known in older systems as Qi, prana, or chakras; organising frameworks widely described in traditional medicine and alternative health, whose mechanisms modern instruments have not yet placed.

Electric fields: the body as an electrical system

A nerve firing is not a metaphor. It is an actual electrical event — a brief reversal of the potential across a thin membrane, from negative to positive and back, travelling down the cell like a wave. The heart coordinates these signals across billions of cells at once, which is what an electrocardiogram records at the skin surface.

What is remarkable is the scale. The field across a single cell membrane is enormous — on the order of ten million volts per metre — because the membrane is so thin. External electric fields from wiring, appliances, or power lines are a tiny fraction of that. It is worth holding that gap in mind in any discussion of electric effects on the body — a point often missing from public debate. Amplitude alone does not rule out other mechanisms by which external fields might act on tissue; it is simply context.

Magnetic fields: the heart, the Earth, and the background you live in

The heart generates the strongest magnetic field your body produces — strong enough to be picked up a metre or more from the chest with sensitive magnetometers, which is the basis of magnetocardiography and the work of the HeartMath Institute on heart coherence. Compared with the Earth’s geomagnetic field, that cardiac field is still vanishingly small — roughly a million times weaker. The geomagnetic field is the magnetic context the body has always lived in; it changes on its own rhythms and is perturbed by solar activity, which is where the story starts to get interesting.

The body's magnetic context is not only internal; it sits inside Earth's changing geomagnetic field.

Some magnetic fields are also used therapeutically. Pulsed electromagnetic field therapy, or PEMF, applies low-frequency oscillating fields to tissue, and there is peer-reviewed evidence from controlled trials for effects on bone healing and pain. The body is not magnetically inert — it responds, when the parameters match.

Gravity and mechanical load as biological signals

Gravity is not electromagnetic, but it is continuous and pervasive, and the body has receptors for it. Cells read mechanical load through the cytoskeleton — their internal scaffolding — and through mechanosensitive ion channels at the membrane. That load shapes gene expression, inflammation, and tissue repair. Mechanical loading is a biological signal, not a structural inconvenience.

Rhythmic mechanical inputs — swinging, rocking, gentle whole-body vibration — reach further into physiology than the inner ear alone. They activate the vestibular system, of course, but they also influence lymphatic flow, postural muscle tone, circulation, and sleep onset. The body treats rhythmic load as information, not only as force.

The clearest demonstration of how much the body depends on mechanical load is what happens in its absence. In weightlessness, bone mineral density and muscle mass drop at a rate measured in percent per month, not per year. A rocking chair and an astronaut’s treadmill are variations on the same physiological theme.

Why the kind of radiation matters

Same word, different physics: non-ionising fields do not eject electrons from atoms; ionising radiation can.

Everyday artificial fields differ from natural geomagnetic variation in strength, frequency, and pattern.

One distinction does a great deal of work in any discussion of energy and the body.

Ionising radiation — X-rays, gamma rays, cosmic rays — carries enough energy per photon to eject electrons from atoms, break chemical bonds, and potentially damage DNA. This is the category health physics was built to manage. Non-ionising radiation — radio, microwave, Wi-Fi, mobile signals, infrared, and visible light — does not. It interacts with tissue through different mechanisms, at different intensities, with different health questions attached.

The point worth holding on to is that not all radiation is the same — and in particular, the instincts many people carry from nuclear radiation do not transfer cleanly to the non-ionising range.

Within that non-ionising range, the health questions open up again. International guidelines mostly protect against tissue heating, which is well understood. A growing body of research, though, points to possible non-thermal effects at chronic, low-level exposure — a question that is far from settled. Switzerland has already written precautionary limits into law for sensitive locations like homes and schools, anticipating that this question may yet be answered on the side of effects that heating-based standards do not capture.

Light: timing, repair, and the cells’ own photons

Light is, strictly speaking, electromagnetic radiation — the narrow band the eye responds to — but it is worth giving it its own category rather than folding it into the non-ionising section. One reason is mechanism: light acts on the body through photochemistry, triggering specific molecular changes — and through other channels besides. Another is that traditional systems across very different cultures have long read light as a carrier of information, and sometimes as a form of energy the body itself can take up and redistribute. Reasons enough to keep it in a place of its own.

Solar radiation is environmental timing information as well as energy input.

Three channels of the measurable work matter most for everyday health.

Circadian timing. A specialised set of cells in the retina, tuned to short-wavelength blue light, sends timing signals to the brain’s master clock. When there is blue light in your eyes, melatonin stays suppressed, which is why evening screen time delays sleep onset and why the hour of your first morning daylight organises the rest of your day.
Vitamin D synthesis. A narrow slice of ultraviolet light converts a molecule in the skin into the precursor to vitamin D. No other molecule in the body depends so directly on sunlight.
Red and near-infrared light therapy. At low intensities, red and near-infrared wavelengths interact with mitochondria and appear, from a growing clinical literature, to support cellular repair.

Light is not only something the body receives from outside. Living cells emit it too — in very small amounts, but steadily and reproducibly, as a faint trickle of photons measurable with photomultiplier tubes. Research associated with Prof. Fritz-Albert Popp and the International Institute of Biophysics has called these biophotons. The emission is real; whether cells use their own light as a signal, or whether it is an incidental by-product of metabolism, is still open. A fascinating question — and one that sits naturally next to the older intuition that light also carries information.

Biophoton discussions belong in a wider context of weak optical signals and should be read cautiously.

Natural electromagnetic influences: solar and atmospheric

The body did not evolve in a field-free environment. The Earth is surrounded by layered rhythms of solar, geomagnetic, and atmospheric activity, and a few illustrative examples of how they connect back to human biology are worth naming.

Heliobiology looks at how solar events — particularly geomagnetic storms — correlate with changes in heart rate variability, sleep, and cardiovascular endpoints at the population level. The correlation is reasonably robust; the mechanism is still being worked out. This site has a companion article on heliobiology that takes the physics apart in more detail.
Sferics are the very slow electromagnetic pulses weather fronts generate in the lower atmosphere. The German biometeorologist Hans Baumer spent decades documenting them with simple antennas and linking their activity to weather-sensitivity symptoms — headaches, joint pain, disturbed sleep on particular kinds of frontal days. Outside the German-speaking literature the topic has barely been picked up, which makes it one of the clearer examples of an easily measurable natural field that biometeorology has yet to integrate.
Magnetoreception is the reason migratory birds navigate using the Earth’s geomagnetic field. Whether humans retain any form of that sensitivity is an open and genuinely interesting question, with some suggestive evidence, some null results, and no consensus yet.

We already live inside a physical system that influences us continuously — a fact that sits almost entirely outside everyday health conversations. Taking it seriously opens up a layer of health that has little to do with the clinic and a great deal to do with the environment the body is embedded in, and how to adjust to it. A large part of what SolarHealth works on sits exactly there.

The older physics of the body

Traditional Chinese Medicine, Ayurveda, and yogic anatomy describe the body as an organised field of energies: Qi, prana, chakras, meridians. The vocabulary is older than the physics we just walked through, and the first thing worth noticing is that the idea of a field — a continuous, organising influence distributed through space — is itself very old. Long before magnetometers or cell recordings, these traditions were mapping the body as a structured field, with considerable internal consistency and, in places, striking clinical staying power.

Older medical traditions describe body organisation differently; this section treats them as historical frames, not proof.

Their methods were different from a physics bench. Careful observation across many patients and many generations, sensing through touch and attention, transmission of cases from teacher to student — not the methods of modern instrumentation, but not nothing either. Producing reliable clinical results — acupuncture is the clearest example — without a mechanism any instrument has yet pinned down sits closer to the frontier of physics than to its rejection.

What this leaves open is a real question, not a settled one. Qi may turn out to map onto some combination of bioelectrical, biochemical, and mechanical signalling that current instruments can already see in parts but not as a whole. The chakras may correspond, at least loosely, to the major nerve plexuses and endocrine centres along the midline, with the field language capturing the integration between them. Or the traditions may be tracking something instruments are simply not yet tuned to detect. Either way, continuing to look has more to offer than treating the question as already closed.

Applications in alternative health

Several of the fields above have found their way into practices that blend physics with traditions of embodied knowledge.

PEMF — pulsed electromagnetic field therapy, used for cellular regeneration, pain relief, and inflammation, with a peer-reviewed evidence base for certain indications.
Chakra and yoga practices — structured ways of combining posture, breath, and attention, drawing on a traditional anatomy of the body as a layered field.
Red and near-infrared light therapy — targeted wavelengths delivered at low intensities, with a growing clinical literature on tissue repair, skin, and recovery.
Gravity-based methods — rocking, swinging, rebounding, whole-body vibration. The physical input is obvious; the reach into the body’s rhythms and regulation is wider than a single mechanism can yet account for.
Bioresonance — uses measurable physical properties (impedance, electromagnetic frequencies) to read patterns physiology has not yet mapped. The physics of the signal is clear; the interpretation belongs to a tradition instrumentation has yet to catch up with.
Applied kinesiology — uses the body itself as the instrument, through muscle-response testing. There is no agreed physical model for what is being read, which is part of why it sits where it does in the landscape.

Body practices are discussed here as embodied regulation, not as a substitute for medical care.

Why this becomes environmental health

Health physics in the broader sense — the physics of a living body, not only its radiation exposure — is interesting because so many different kinds of physics meet inside the body at once. Electric and magnetic signalling, mechanical load, visible and non-visible light, atmospheric and solar rhythms, and the older organising descriptions traditions have left us: none of them works in isolation, and none is a complete picture on its own.

That is why SolarHealth keeps coming back to environmental health. Environmental health is what you get when you take this combined picture seriously and ask how to live well inside it — how to set up a home, a workplace, a day, and a night so that the physical environment works with physiology rather than quietly against it. The rest of this site is, in one way or another, an attempt to answer that question piece by piece.

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General Disclaimer

This content is for educational and informational purposes only. It does not provide medical advice, diagnosis, or treatment, and should not be used as the basis for personal health decisions. If you have symptoms or health concerns, consult a qualified health professional.