Sperti Vitamin D Lamp Review: Does It Actually Work?

Just find out you’re low in vitamin D? Or maybe it’s winter and you just miss the holy lightbulb in the sky?

Well, I bought, used, and tested the Sperti Sunlamp, and in this review, we cover everything you need to know before you make the big purchase.

Does the Sperti Vitamin D Sun Lamp Work?

Yes!

The Sperti vitamin D lamp is an FDA-approved class II medical device that has been proven to increase vitamin D levels.

There’s definitely enough UVB in this lamp to produce vitamin D!

In fact, Sperti conducted their own study to get FDA approval.

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The Sperti Vitamin D Study

In this study, 5 participants with skin types 2 and 3, were irradiated for 5 minutes, 3 times per week for 4 weeks.

At the end of the study, all 5 subjects had an average increase in vitamin D levels of 47.5%.

Not bad! And since you can use the lamp more than they did in this study, these results can be improved upon!

How to Use the Sperti Vitamin D Lamp

Let’s go over the recommendations for using the Sperti lamp.

How Often Should You Use It?

During the first week, Sperti recommends using the lamp for 3 minutes every other day.

If this doesn’t cause you to burn, they recommend increasing this duration to 4 minutes during week two.

While on week three and beyond, the recommended exposure duration is capped at 5 minutes max.

While Sperti recommends alternating front and back on separate days, I see no mechanistic reason as to why you couldn’t do separate areas of your body on the same day should you wish.

How to Use the Lamp

Since the recommended distance is 15 inches, you’ll need to make sure you aren’t any closer than this.

When using the lamp on your front side, you can use your arm as a gauge of distance. Most people will find that while forming a fist, from your elbow to your fist is about 15 inches. So you can use this as a gauge.

However, since you can’t do this for your backside, an easier way may be to find a place where you can place the lamp 15 inches from the edge of a surface.

This way, you know that when you stand right at the edge, you’re in the right spot.

Are Vitamin D Lamps Safe?

Vitamin D lamps are safe if you use them for the recommended amount of time and don’t stand too close.

Just like the sun, you can damage your skin if you use the Sperti lamp too long, so don’t!

There are certain medical conditions and lifestyle behaviors that can increase your susceptibility to photodamage from ultraviolet light.

Some examples of things that can increase photosensitivity:

• Birth control
• Perfumes and lotions containing essential oils
• NSAIDS like ibuprofen
• Vegetable seed oil consumption
• and much more!

Here is a bigger list provided by Sperti in their product manual:

So just know that there are things you can and should be doing to improve your sensitivity to damage from the sunlight.

Who Can Use the Lamp?

In addition, Sperti warns that those with type 1 skin should not use their device. Think pale ginger, these are the Ron Weasly types.

This is because these folks have very little adaptation to ultraviolet light and should exercise caution when using a powerful lamp like the Sperti.

If you have a paler complexion, be sure to limit your exposure time and distance from the lamp wisely and watch for redness for 48 hours following use.

Does the Sperti Vitamin D Lamp Give You a Tan?

It’s not intended for tanning, and Sperti claims it will not tan your skin.

Though there’s certainly plenty of UVA in this lamp, which is the part of the sun primarily responsible for the tanning effect.

I suspect that it will produce a mild tan over time in some individuals who tan well.

The Benefits of a Vitamin D Lamp

There are many benefits to exposure to sunlight and ultraviolet light you may or may not be aware of.

As the authors of this study point out, exposure to sunlight is necessary for public health!

For one, exposure to UVB rays from the sun gives us our primary source of vitamin D! Many of us in the United States will struggle to produce enough throughout the year and could benefit greatly from a vitamin D lamp.

According to this study, it also appears as though UVB exposure on the skin helps modulate the gut microbiome! These are preliminary findings but they go to show us that there’s more at work here than we may know about.

We also produce natural opiates called endorphins when exposed to ultraviolet radiation, this is why being in the sun feels so good!

We also now know that ultraviolet exposure on the skin produces nitric oxide which helps a lot with blood flow.

Need I go on? The sun is a powerful and useful resource as long as you don’t burn yourself to a crisp.

The immense benefits of UVB and sunlight are summarized greatly in Dr. Holick’s book The Vitamin D Solution, which I highly recommend you check out!

Testing the Sperti Vitamin D Lamp

Of course, we put our UV spectrometer to the test here!

Spectral UV Light Output

I wanted to see how much UVB and UVA this puts out and where.

Here’s the spectral output:

As you can see, it mainly emits UV with a few spikes in the visible range. Here’s an output graph showing the relative output in mW/m2 at the recommended range of 15 inches:

UVB ranges from 280 to 315nm, while UVA ranges from 315 to 400nm; looking closer at the UV range, we can see that the Sperti is putting out about 42% UVB and 56% UVA.

There is plenty of UVB for vitamin D production, and the presence of UVA can help regulate this and contribute to the production of endorphins.

Flicker

I thought it would be worth checking the flicker as well, even though visual stimulus is not the goal of this product.

We detected a tiny ~2% flicker at 120 Hz, not too bad.

Magnetic and Electric Fields

Finally, I was curious about EMFs, so I also checked these using an EMF GQ-390.

Fortunately, there’s nothing to be found here. There is a magnetic field starting at around 6″ from the unit, but since you won’t spend any time in that range, it doesn’t matter.

EMF testing was done using the GQ EMF-390.

Should You Buy It?

Since the Sperti Sun Lamp comes with a 60-day money-back guarantee, there’s almost no reason not to try it out!

It’s portable, super easy to use, and it’s an excellent way to produce vitamin D and endorphins throughout the cold winter months.

If that doesn’t sell you on it, one look at Sperti’s trust pilot page will show you just how much users love this product!

My verdict

Sperti Vitamin D Sunlamp

• Pro: Proven to increase vitamin D in clinical trials
• Pro: 60-day money-back guarantee
• Pro: Extremely easy to use

• Con: Large upfront cost
• Con: Only radiates part of your body at once

Sperti store

See the lab results

12 in from bulbs · measured Oct 1, 2026

428lux

Brightness

25161K

Color temp

2.14%

Flicker

Spectrum

10

Near-infraredUltraviolet436 nm

3004005006007008009001000

Wavelength (nm)

Spectrum chart. Sperti Vitamin D Sunlamp, 25161K, melanopic DER 0.94.

Flicker, as tested

01

020406080100

Time (ms)

Chart by time. Sperti Vitamin D Sunlamp.