Infrared (IR) radiation affects the human body mainly by transferring heat, but its effects depend on the wavelength, intensity, and duration of exposure.
1. Heating Effect
- IR radiation is absorbed by the skin and underlying tissues, causing molecules to vibrate more quickly.
- This increases local temperature, improving blood circulation and muscle relaxation.
- This effect is why IR is used in heat therapy lamps, saunas, and physiotherapy.
2. Beneficial Medical Uses
- Pain relief: Infrared heat can soothe sore muscles and joints.
- Wound healing: Low-level IR therapy may stimulate tissue repair and reduce inflammation.
- Improved circulation: Expands blood vessels, promoting oxygen and nutrient delivery.
3. Potential Risks
- Overexposure can cause skin burns, similar to heat burns.
- Prolonged intense exposure near the eyes may damage the retina or cornea.
- Far-infrared exposure from normal environmental sources (like sunlight) is generally harmless at typical levels.
4. Everyday Exposure
- Humans naturally emit and absorb infrared radiation — it’s part of normal heat exchange with the environment.
- Common sources: sunlight, fires, heaters, and electronic devices.