Rosenthal notes that the lights “used in almost all research studies … have an illuminated surface that is at least about one foot square.”
Although many SAD lamps fit the above specifications, we discounted a number of them because of their high price, overly cumbersome design, too-small size, or dubious claims about features like “ion therapy.”
Because we are not qualified or equipped to evaluate SAD lamps for efficacy, we focused instead on how easy they were to use, how much space they took up on a tabletop, and whether they met their stated specs, including their total size and weight, light-face dimensions, cord lengths, and approximate light intensities. In a nonscientific test, we compared lux readings obtained with a commercial luxmeter to check for any significant inconsistencies between stated light intensities and real-world readings.
For this review, we focused on light therapy lamps. We did not consider dawn simulators, sunrise alarm clocks, or so-called light therapy glasses.
Our pick: Carex Day-Light Classic Plus
Top pick
Carex Day-Light Classic Plus
The best light therapy lamp
This light has all of the specs our expert sources recommend, as well as a reasonable price and a generous warranty.
The Carex Day-Light Classic Plus has the largest light face of all our picks and an impressive record of efficacy, as reported in customer reviews and academic research alike. At a distance of 12 inches, this lamp projects 10,000 lux of “99.3 percent UV-free” LED light from its 15½-by-12½-inch lamp face, the same amount of lux as all of our other picks provide and the minimum lux that any SAD lamp needs to be therapeutically effective according to the doctors we interviewed. The lamp face mounts to a weighted horseshoe base by way of an adjustable arm. This arm allows you to adjust the lamp’s angle and vertical position, reducing overall glare and increasing the flexibility of where and how you can use the lamp. For instance, you can set up the Day-Light Classic Plus in such a way that it allows you to read a book beneath it while keeping most of your face positioned well within the therapeutic 12-inch range of the lamp face. In contrast, to read in front of lamps that sit directly on a desk, you would need to either place the book upright between you and the lamp, which would shield you from some of the light, or lay the book down in front of you, possibly extending your position outside of the lamp’s therapeutic range.
Assembling the Day-Light Classic Plus is easy and takes less than five minutes. An on/off switch on its side powers the lamp; when switched on, it starts illuminating instantly, in one of two intensities (7,000 or 10,000 lux). Fully extended, the Day-Light Classic Plus is 28½ inches tall. The lamp angle can swing approximately 65 degrees from fully vertical to nearly horizontal, which adds flexibility, though this design makes the entire lamp more cumbersome to move around compared with other lamps we’ve tried.
Compared with the cooler tones of other lamps, the Day-Light Classic Plus emits a pleasant, warm light with a color temperature of 4,000 Kelvin. You can also adjust the intensity, choosing between a high setting (10,000 lux) and a low setting (7,000 lux). Unlike on our also-great pick, this model’s cover, which protects the LED lights, creates an airtight seal, which makes the lamp easier to keep clean. The lamp comes with a standard AWG 6-foot grounded power cord, which is plenty long enough for most people’s needs and interchangeable if it gets lost. That interchangeability also means you can buy a longer AWG cord and use that instead if you need to.
The Day-Light has been used for years by scientists and physicians who study and treat SAD. The Center for Environmental Therapeutics, a nonprofit collective of scientists and clinicians dedicated to research and education about environmental therapies, previously recommended the Day-Light for years. According to psychologist Elizabeth Saenger, who was the CET’s director of education at the time of our interview, it’s the go-to light for many clinical trials that aim to study the effectiveness of light therapy. In October 2017, former CET board member Dorothy K. Sit, MD, and her colleagues used the Day-Light in a study described in an American Journal of Psychiatry paper, “Adjunctive Bright Light Therapy for Bipolar Depression: A Randomized Double-Blind Placebo-Controlled Trial.” A January 2016 article in New York Magazine also touted the Day-Light Classic Plus, quoting psychiatrist James Phelps’s description of it as the “official research rig.”
Flaws but not dealbreakers
The Day-Light Classic Plus is unwieldy and, some would argue, unattractive. The weighted base has a large (12-by-16-inch) footprint, so this lamp is not ideal for smaller spaces. If you don’t like the way it looks, you may prefer the simpler design of our also-great pick or our compact budget pick.
Like any heat-producing device, the lamp should be used in an open, ventilated space (a company spokesperson said to avoid putting it on a desk with a hutch, for example).
Carex’s five-year warranty for the Day-Light Classic Plus does not apply to “use other than for personal, family or household purposes and excludes shipping and handling charges.”
Also great: Northern Light Technologies Boxelite
Also great
Northern Light Technologies Boxelite
More streamlined, warmer hue
Of all the larger light therapy lamps we considered, the Boxelite has the most unobtrusive design.
If design is your priority, we like the Northern Light Technologies Boxelite. This lamp is more expensive than our top pick but looks the sharpest on a desk or table. Similar to the Day-Light Classic Plus, the Boxelite provides 10,000 lux at a distance of 14 inches, and it emits light from a 15-by-12-inch face. According to Northern Light Technologies, the light is fully UV-free, a slight enhancement over our top pick’s “99.3% UV-free” claim. The Boxelite provides an even warmer light than the Day-Light Classic Plus, with a 3,500-Kelvin color temperature. The Boxelite is not adjustable, but its slim, basic design helps it look the least obtrusive of the lamps we considered.
An on/off switch at the base powers the lamp. The bulbs take a few seconds to illuminate, but that is normal for fluorescent bulbs. The lamp also comes with a 7-foot cord, the longest of any of our picks.
Our favorite aspect of the Boxelite is its sleek design. The Boxelite has a picture-frame setup, minimal design with few accents, and clean edges. The back of the Boxelite is contained in a single smooth, black panel. It also comes with a seven-year warranty, longer coverage than for our pick. Note, though, that this warranty (PDF) covers everything but the tubes, and the customer is responsible for the shipping costs to send faulty units to Northern Light Technologies.
Our main two issues with the Boxelite are its lack of adjustability and its higher price, although it does come with that seven-year warranty. Also, since the Boxelite’s plastic cover does not feature an airtight seal (unlike on our other two picks), dust and grime easily slip into the hard-to-clean space between the cover and the lights.
Budget pick: Verilux HappyLight Luxe
Budget pick
Verilux HappyLight Luxe
Compact design, less powerful
The compact HappyLight Luxe shines brightly in multiple color temperatures and brightness levels, and it has an automated shutoff feature. It’s the best sub-$100 lamp we’ve considered. However, its light is less powerful than that of our other picks, and it provides 10,000 lux only at a distance of six inches.
In side-by-side comparisons, the light output of the Verilux HappyLight Luxe was significantly lower than that of our other two picks. However, this small lamp is a solid option for newcomers to light therapy who don’t have the space or the budget for our top pick or also-great pick. At less than a foot tall and 7½ inches wide, it also packs easily for travel. The HappyLight Luxe’s 9-by-6-inch light surface still shines brightly, though not as brightly as those on our other, larger picks. According to Verilux, the lamp’s claimed 10,000-lux, “UV-free” light projection is adjustable from 3,500 to 5,000 Kelvin, so you can pick the light warmth that feels best to you.
However, the 10,000-lux is only feasible at a distance of six inche