Understanding DHA Development in Spray Tans: Why It Takes 24 Hours for a Tan To ‘Fully Develop’

As a spray tan artist, understanding the science behind DHA (Dihydroxyacetone) and how it interacts with the skin is crucial for achieving the best possible results for your clients. One of the most frequent questions clients ask is why their tan looks so different in the first few hours after a spray tan, compared to 24 hours later. This can be a bit confusing, especially since the initial ‘bronzing’ effect from the spray tan is visible immediately (thanks to our stunning bronzers). The key to understanding this lies in how DHA works and why it needs time to fully develop on the skin. Often times- clients do not understand that spray tans are a scientific reaction happening right on their skin.

First We Have To Cover… What is DHA?

DHA, or Dihydroxyacetone, is the active ingredient in spray tan solutions, self tanners, face tan waters, tan extenders, etc. It’s a simple sugar derived from plant sources, and when applied to the skin, it interacts with the amino acids (dead skin cells) in the outer layer of the skin. This reaction causes a temporary color change, giving your clients that gorgeous bronze.

However, there’s more to the story. The color that appears right after that first rinse is not the final result. It’s only a part of the process, and the full development of the tan takes time.

Why Does It Take 24 Hours for DHA to Fully Develop?

While it’s easy to think that the tan is complete right after the spray tan session, the true, final color emerges after 24 hours. This is because DHA doesn’t immediately create the full color—it takes time to develop. Here’s a closer look at why it takes so long for DHA to fully show its effects:

1. The Chemical Reaction Takes Time

When DHA is applied to the skin, it doesn’t just “stain” the surface. Instead, it undergoes a chemical reaction with the amino acids in the outer layer of the skin. This process is called the Maillard reaction (the same process that causes browning in food). However, this reaction is gradual and takes time to complete. The reaction between DHA and the amino acids produces the bronze color, and while this starts right away, it continues to deepen over time (up to 24 hours- and for some… past that!)

2. Skin Type and Hydration Play a Role

Different skin types can influence the way DHA develops. For example, dry skin may not react as evenly or intensely as well-hydrated skin. Skin that is hydrated absorbs DHA more efficiently, resulting in a smoother and more consistent tan. However, dry patches can lead to uneven development, with some areas becoming darker than others.

Additionally, the process of skin hydration also affects the timing. While DHA can start to react immediately, it requires sufficient moisture to create the most even, natural-looking color. Without the proper moisture balance, the DHA reaction can be delayed.

3. Sweat, Water, and Friction Can Affect Development

For the best results, it’s crucial that your clients avoid sweating, showering, or engaging in activities that could cause friction during the first 8–12 hours after their spray tan (the most crucial hours of a tans development). These factors can disrupt the DHA reaction and interfere with the final result.

Once the DHA has had time to fully develop, the tan becomes stable and resistant to these external factors. That’s why the 24-hour period is key—it’s when the tan has fully set and is less likely to be impacted by sweat or water exposure.

What Does This Mean for Your Clients?

As a spray tan artist, it's important to communicate the 24-hour development timeline to your clients. Here’s how you can manage their expectations:

• Explain the Science: Educating your clients about the process will help them understand that the perfect tan takes time to develop. The bronzer they see immediately after the session is a color guide as well as a light stain that sets the ‘tone’ of the tan, the tan itself will deepen and darken over the next 24 hours.

• Teach clients how to properly ‘rinse’: Long, hot, or soapy showers in what should be the first ‘lukewarm soap free water rinse’ will cause for the tan to not develop as it will alter the DHA reaction. This needs to be a quick rinse with the only purpose of washing bronzers off/discontinuing the ongoing development of DHA.

• Moisturize for Longevity: To maintain the tan and allow for an even fade, recommend that your clients moisturize daily post tan with a spray tan safe body lotion Glazed Sunless Daily Body Cream — Glazed Sunless. This will keep the skin hydrated, ensuring that the DHA reacts as evenly as possible.

Conclusion

Understanding that DHA takes time to fully develop is an essential part of being a knowledgeable and successful spray tan artist. By explaining why it takes 24 hours for the tan to reach its final, rich color, you help set proper expectations with your clients and ensure they’re satisfied with the results. It’s not just about the immediate bronzing effect—it’s about the full, beautiful glow that develops over the course of an entire day.

By educating your clients on the science of DHA, you’re not only improving their experience but also boosting your professionalism as a spray tan artist. The more they understand, the more likely they are to be happy with their final results—and that’s the ultimate goal.

If your client is getting sprayed for an event- it is best to have them get a tan 48 hours before said event to ensure that tan is fully developed.