Full Spectrum vs. Fluorescent Light Bulbs

Full Spectrum vs. Fluorescent Light Bulbs. Products labeled "full spectrum" or "daylight" are manufactured to cater to our preferences for natural light. However "full spectrum" is not a technical term, and often premium-priced full-spectrum bulbs have identical properties to cheaper cold-white fluorescent bulbs.

"Full Spectrum" is primarily a marketing phrase for high-quality fluorescent bulbs.

Full Spectrum Fluorescent

While some incandescent bulbs are now called full spectrum, the majority of full-spectrum products are fluorescent. Most "full spectrum" incandescent products are standard high-wattage light bulbs with tinted glass for filtering out yellows and reds, producing a whiter light.


Typically, full-spectrum fluorescents have a cold-white color that mimics bright midday sun, as well as a high--for a fluorescent--color-rendering rating. However, the term has no clear definition, and the exact meaning of "full spectrum" will vary between manufacturers.


Promotional materials for full-spectrum fluorescents assert a wide variety of health benefits, such as improved vitamin D absorption and reduced dental decay. But according to the Lighting Research Center, full-spectrum lighting does not provide any more health benefits than other artificial light sources.

Light Therapy

Prolonged exposure to an extremely bright full-spectrum fluorescent source may help treat Seasonal Affective Disorder (SAD); however, studies remain inconclusive. There is no evidence that simply using full-spectrum light bulbs in a home will help SAD.


Studies regarding the possible psychological benefits from full-spectrum lighting have been inconclusive. The National Research Council of Canada notes that test subjects will always be aware of changes to their lighting environment, making it difficult to control for a placebo effect.


  • Lighting Research Center: Full-Spectrum Light Sources
  • National Research Council, Canada; A critical examination of perceptual and cognitive effects attributed to full-spectrum fluorescent lighting
  • National Research Council, Canada; "Full-spectrum fluorescent lighting: a review of its effects on physiology and health"
  • Mayo Clinic: Seasonal Affective Disorder