★★★★★ 4.6 stars from 145 Exponent reviews

Tired of Vitamin C turning brown? Mix yours fresh each morning

Brightening Boost keeps 10% pure L-Ascorbic Acid in powder form until use, then activates it with a hyaluronic acid hydrator in your palm. A 30-dose system for brighter, more even-looking skin without relying on a pre-mixed bottle.

30 fresh doses. $128 Power Serum.

10% pure L-Ascorbic Acid Active powder kept fresh until use 30-dose Power Serum Available at Nordstrom + Credo ★★★★★ 4.6 stars from 145 Exponent reviews
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Fresh-Mix Vitamin C

The problem is not Vitamin C. It is what happens after it sits in a bottle.

Pure L-Ascorbic Acid is one of the most effective forms of Vitamin C, but Exponent's Vitamin C collection notes that it is fragile and prone to degradation unless it is kept in powder form and activated fresh.

That is why Brightening Boost does not ask you to trust a pre-mixed serum. Stamp the powder, pump the hyaluronic acid hydrator, and mix a fresh dose right before it goes on your skin.

Fresh-Mix Vitamin CThe problem is not Vitamin C. It is what happens after it sits in a bottle.Pure L-Ascorbic Acid is one of the most effective forms of Vitamin C, but Exponent's Vitamin C collection notes that it is fragile and prone to degradation unless it is kept in powder form and activated fresh.That is why Brightening Boost does not ask you to trust a pre-mixed serum. Stamp the powder, pump the hyaluronic acid hydrator, and mix a fresh dose right before it goes on your skin.
powder until the moment you mix
Clinical Brightening Proof

VISIA-measured proof for the brightening claim

In independent clinical testing, 28 female subjects completed a multi-week study using VISIA Image Analysis Pro and lesion counting with a board-certified dermatologist and trained technician.

After two weeks, VISIA imaging showed a noticeable decrease in subdermal sun spots. After four weeks, 66% of subjects showed increased brightness and decreased discoloration.

Clinical Brightening ProofVISIA-measured proof for the brightening claimIn independent clinical testing, 28 female subjects completed a multi-week study using VISIA Image Analysis Pro and lesion counting with a board-certified dermatologist and trained technician.After two weeks, VISIA imaging showed a noticeable decrease in subdermal sun spots. After four weeks, 66% of subjects showed increased brightness and decreased discoloration.
clinical results
How It Works

Mix your morning dose in three steps

Do not rely on Vitamin C that has been sitting pre-mixed. Use Brightening Boost as the first layer on clean, damp skin in the morning, then layer moisturizer or SPF.

Stamp the Vitamin C powder and pump the hydrator 01

Stamp the Vitamin C powder and pump the hydrator

Stamp one dose of Vitamin C Active Powder and pump the hyaluronic acid hydrator into your palm.

Mix into a fresh serum 02

Mix into a fresh serum

Blend the powder and hydrator together right before applying.

Apply before moisturizer or SPF 03

Apply before moisturizer or SPF

Smooth over clean, damp skin in the morning, then layer moisturizer or sunscreen.

What Is Included

What you get in the 30-dose Power Serum

A complete fresh-mix system for $128, with the powder and hydrator designed to work together.

The full system, not another serum bottle

Includes the Precision Dispenser with Vitamin C Powder, 3g, plus the Pump with Quadruple Hyaluronic Acid Hydrator, 15mL. Together, they deliver 30 fresh-mix doses.

  • 30 fresh Vitamin C doses
  • 10% pure L-Ascorbic Acid powder
  • Quadruple Hyaluronic Acid Hydrator
  • 3g Vitamin C powder + 15mL hydrator
  • $128.00 Power Serum
  • Available at Nordstrom + Credo
Get Brightening Boost Vitamin C
Brightening Boost Vitamin C Power Serum product render
Customer Reviews

Positive reviews from Vitamin C customers

★★★★★

"Noticeable results, especially in evening discoloration and brightening tone."

Tamela S.
★★★★★

"Best Vitamin C brightener I have ever used. After decades of sun exposure, daily use has markedly improved skin tone. Gentle yet effective."

Mary C.
★★★★★

"Within a week my sunspots lightened, my skin is clearer and brighter. I will not use anything else, and trust me, I have tried everything."

Rachel B.
★★★★★

"It is the only one I have ever seen real impact from, even compared to SkinCeuticals. Now our whole chat group subscribed."

Kristin K.
★★★★★

"I have wanted to try a Vitamin C for the longest time. I am so glad I chose this brand. I have seen great results too."

Iliana N.
★★★★★

"This product does lighten dark spots and revives my skin."

Tracy M.
★★★★★

"The texture is incredible. The ritual is quick and is my favorite part of my routine."

Lauren S.
★★★★★

"I have been using Exponent's Vitamin C product for several months and have had fantastic results."

Verified customer
★★★★★

"Love this so much. Use it daily. My skin feels hydrated and brighter. Will definitely reorder."

Verified customer
★★★★★

"I have brighter skin after using Vitamin C from Exponent. Much more effective than other products I have used."

Melody
FAQ

Answers before you make it your morning Vitamin C

Positive, source-backed answers on freshness, results, routine, sensitive skin, and what is included.

How do I use it in my routine?

Use it in the morning as your first layer on clean, damp skin. Layer underneath moisturizer or SPF.

How does fresh mixing solve the bottled Vitamin C problem?

Exponent notes that pure L-Ascorbic Acid is effective but fragile and prone to degradation unless it is kept in powder form and activated fresh. Brightening Boost keeps the active as powder until you mix it in your palm.

Is it made for sensitive skin?

Brightening Boost is formulated for sensitive skin and pairs 10% pure L-Ascorbic Acid with a hyaluronic acid hydrator. If you are unsure how your skin will respond, patch test first or ask your skincare professional.

What results were measured in clinical testing?

In clinical testing, VISIA imaging showed a noticeable decrease in subdermal sun spots after two weeks. After four weeks, 66% of subjects showed increased brightness and decreased discoloration.

Can I use it with retinol?

Vitamin C is positioned as the morning active. Retinol is usually used in the evening. If you use both, keep Vitamin C for AM and retinol for PM unless your skincare professional advises otherwise.

What comes in the Power Serum?

The Power Serum includes the Precision Dispenser with Vitamin C Powder, 3g, and the Pump with Quadruple Hyaluronic Acid Hydrator, 15mL. The Power system gives you 30 fresh-mix doses.

Brightening Boost Vitamin C

Stop guessing how fresh your Vitamin C is

Get the 30-dose Power Serum with 10% pure L-Ascorbic Acid powder and hyaluronic acid hydrator, built for a fresh morning dose and brighter, more even-looking skin.

Get Brightening Boost Vitamin C
4.6 stars from 145 reviews 30 fresh doses $128.00 Power Serum Direct checkout