We Treat Our Tomatoes Better Than Ourselves
Every year around this time I set up my seedlings with full-spectrum grow lights. It's nonnegotiable. Plants need the complete spectrum to grow properly. We figured that out decades ago. Even the rinky-dink Amazon grow lights are full spectrum.
But here's what kept bugging me: the stuff we make nonnegotiable for plants? It's hard to find for humans. And we need it just as much.
For the first time in human history, we're living under incomplete light.
Most architects in the Pacific Northwest have been focused on maximizing daylight—which is smart given our gray winters—but we haven't been paying enough attention to the quality of artificial light that fills in the rest. I didn't either, until I started asking why my tomatoes were getting better spectrum than my clients.
The Problem We Created
Most LEDs are designed for energy efficiency, not human biology. They concentrate light in the visible range; heavy on blue, weak on red, and basically zero infrared. The design is intentional. Engineers asked "why waste energy producing wavelengths humans can't see?"
Makes sense from an efficiency standpoint. Terrible for everything else.
Dr. Roger Seheult put it well: "We were never getting blue light without red light. Now we're starting to get blue light without red light."
That's new. For all of human history—fire, candles, oil lamps, incandescent bulbs—every light source gave us a broad, continuous spectrum. LEDs are the first time we're getting one part without the other. And our bodies don't know what to do with that.
Why It Matters
As architects in the Pacific Northwest, we've historically focused on efficiency and aesthetics, which made sense. But the LED revolution happened so fast that the industry hasn't caught up to what we're losing in the transition from incandescent to solid-state lighting.
It's not that anyone did anything wrong. It's that the technology changed faster than our understanding of its implications.
Sleep and circadian rhythm.
Your body has an internal clock set primarily by light. Blue-rich light in the morning tells your brain "it's daytime, be alert." The absence of blue at night—and the presence of red and infrared like from a fire—tells your body "wind down, produce melatonin, get ready for sleep."
When you're under bright LEDs with that blue spike at 9 PM, your brain thinks it's still midday. Melatonin gets suppressed. Sleep quality drops. A lot of sleep problems might actually be light problems.
Mood and energy.
Natural light increases serotonin. In darker months or poorly lit interiors, serotonin drops and you end up with low mood and low energy. There was a study—office workers with access to natural light versus those in dim interior offices slept 37 minutes longer per night and scored higher on cognitive tests. Just from having windows.
Eye health and vision.
High blue light without the balancing red component causes eye strain and potentially long-term issues. A recent study swapped out standard LEDs for incandescent bulbs in an office and saw a 25% improvement in color vision. People could distinguish colors better under the broader spectrum.
“We’re essentially malnourishing our eyes with incomplete light.”
What We're Missing
Old incandescent bulbs—the ones that got banned for wasting energy—actually put out a spectrum really close to natural sunlight. A continuous range of wavelengths from blue through red and into infrared.
That "wasted" energy? It was infrared. The warmth you feel from an incandescent bulb got left by the wayside in the name of progress. Our bodies respond to those wavelengths. Red and near-infrared light supports cellular function, helps with circadian signaling, even aids in tissue repair.
LEDs cut all of that out to save energy.
What You Can Do About It
First and most important: maximize natural daylight. The sun is still the best light source—even in the South Sound's gray winters, strategic window placement makes a huge difference.
If you're planning a renovation in Gig Harbor or Tacoma, this is where thinking about light quality early in the design process makes the biggest impact. Window placement, skylights, and light-colored walls that bounce daylight deeper into spaces—these decisions are much harder (and more expensive) to change after construction starts.
When we do need to supplement with artificial light, we can now make much more informed choices about spectrum quality.
When you need artificial light, choose better bulbs. Look for high-CRI full-spectrum LEDs. CRI stands for Color Rendering Index—how accurately the light renders colors compared to natural sunlight. Most cheap LEDs are around 80 CRI. You want 95 or higher.
Don't just trust marketing. If a bulb says "full-spectrum" but doesn't list the CRI or show you a spectral distribution chart, it's probably just regular LED with a fancy name.
Some brands worth checking: Waveform Lighting (Centric Daylight series, 95+ CRI), Yuji LED (high-CRI options), or look for "Soraa" bulbs if you can find them. For a more accessible option, Philips makes some higher-CRI LEDs in their premium lines.
Yes, they cost more than Home Depot bulbs. But they last for years and you're in these spaces every day.
Some options to consider: I’ve put together a list of high-CRI bulbs, table lamps, and floor lamps that actually fit the spec.
Time your light. You want cool, bright, full-spectrum light during the day—maybe 5000K color temperature. That supports alertness and your circadian rhythm.
At night, switch to warm, dim light—2700K or lower. The color of an old incandescent or candlelight. Smart bulbs can automate this, but even just having different bulbs in different lamps and switching which ones you use works.
Layer your lighting. Don't rely on one harsh overhead light. Multiple sources create a more natural environment. During the day, bright overhead lighting mimics skylight. In the evening, use lower lamps that point light upward softly—that mimics firelight, which is what our ancestors wound down by for thousands of years.
If you want to light candles or sit by a fireplace in the evening? That's literally perfect spectrum for nighttime. Almost all red and infrared with minimal blue.
Why This Matters for Design
If you're planning a renovation or building new, this is exactly the kind of thing worth thinking about before the lighting plan is locked in. Once fixtures are installed and wiring is set, it's expensive and disruptive to change.
Early conversations about light quality—not just light quantity—can shape everything from window sizes to fixture selection to electrical planning. We can design spaces that support how your body actually works instead of fighting against it.
But even if you're not renovating, swapping out bulbs in the spaces where you spend the most time makes a real difference. Your home office. Your bedroom. Wherever you read or work.
Small changes. Real impact.
The Irony
We figured this out for tomatoes decades ago. The grow light industry is built on giving plants full-spectrum light because we know they need it.
Maybe it's time we treat ourselves at least as well as our tomatoes.
Watch the full video here:
Planning a custom home or renovation in Gig Harbor, Tacoma, or the South Sound? I can help you think through lighting decisions (and dozens of others) that most people don't consider until it's too late to change them easily.