Pre-release · Formula 003
Mandelic Acid Body Cleanser
The quiet science of staying fresh.
2,000+ people on the pre-release waitlist
- 4.5% mandelic acid
- pH 3.8 formula
- Aluminum-free
- 500 mL / 16.9 fl oz
Freshness
- Addresses the bacteria behind odor, rather than masking it
- Brings skin to a pH that odor-causing bacteria find inhospitable
- Gently lifts the dead skin cells on which those bacteria feed
- Works with natural perspiration, never against it
Skin
- Refines texture for a smoother feel
- Helps clarify pores across the chest and back
- Helps even the appearance of skin tone
- Gentle enough for daily use
- Supported by zinc PCA, niacinamide and prebiotics for a balanced, comfortable skin barrier
Daily use
- Part of your shower, with nothing to reapply
- For the whole body: underarms, chest, back, feet and skin folds
- A single cleanser in place of deodorant, foot spray and body powder
- Rinses clean, leaving no residue or marks on clothing
- Kind to towels and linens, unlike benzoyl peroxide cleansers
- Free from aluminum and baking soda
Founding members receive 15% off their first order at launch. One use per customer, valid for 14 days after launch with the email you sign up with.
- 60-day guarantee
- Complimentary shipping on every bundle
- A single step in the shower. Nothing to reapply.
A familiar day
You showered this morning. By afternoon, you're no longer sure.
- 7:30 AM Out of the shower. Fresh shirt, fresh start.
- 12:30 PM Lunch meeting. You keep your arms close.
- 3:00 PM A quick check in the bathroom. Just to be sure.
- 6:00 PM You wonder who noticed. And why it keeps happening.
It has nothing to do with hygiene. The cause is simply rarely explained.
Sweat isn't the problem. Bacteria are.
Fresh sweat is nearly odorless. The smell appears when bacteria living on your skin break sweat down into odor compounds.
Sweat
Your body's cooling system. Nearly odorless on its own.
Skin bacteria
Staph and Corynebacterium thrive in warm, less acidic underarm skin.
Body odor
The smell is what the bacteria produce, not the sweat itself.
Why nothing stuck
Most products answer the wrong question.
Fragrance covers the smell until it fades. Aluminum blocks sweat but leaves the bacteria alone. So the odor returns, often at the least convenient moment.
“The root cause of the smell actually takes the combination of the bacteria and the sweat.”
- Deodorants Mask odor with fragrance that fades
- Antiperspirants Block sweat, bacteria stay put
- Natural deodorants Conceal odor rather than address its cause
- Body sprays Fragrance on top of odor
- Regular soap Rinses away, bacteria return
A different approach
Change the skin. Not the smell.
Odor-causing bacteria favor the underarm because the skin there is less acidic. Restore its acidity and they struggle. That's the idea dermatologists point to with acids like mandelic acid.
Lower the pH
Underarm skin runs less acidic than the rest of you. An acidic cleanser brings it back toward a range odor bacteria find inhospitable. [7][8][9]
Clear what's there
Mandelic acid works against the bacteria themselves, and exfoliates the dead skin cells they feed on.
Keep it up daily
Every shower resets the conditions, so odor has less chance to build. Nothing masked, nothing blocked.
Why mandelic acid
The gentlest acid for the most sensitive skin.
Underarm skin is thin. Mandelic acid's molecule is twice the size of glycolic acid [5][6], so it absorbs slowly and evenly instead of all at once. That's why it's the acid of choice when irritation is the worry.
“When we're looking at these acids, I think mandelic acid is probably the one that's the most tolerable.”
Meet Formula 003
Built for one job: the bacteria behind odor.
A body wash you already know how to use, formulated around mandelic acid in a gently acidic base.
- Active
- 4.5% mandelic acid
- Formula pH
- 3.8
- Free from
- Aluminum, baking soda, parabens, sulfates
- Use on
- Underarms, chest, back, feet, groin
- Key ingredients
- Mandelic acid, zinc PCA, niacinamide
- Skin feel
- Clean, comfortable
- Aroma
- None (unscented) or light, clean (scented)
- Texture
- Clear gel
- Size
- 500 mL / 16.9 fl oz
How to use it
- 1 · Dispense One pump onto a sponge or loofah.
- 2 · Massage Onto wet skin, from underarms to toes. Allow 60 seconds.
- 3 · Rinse Rinse thoroughly. Nothing to reapply.
What to expect
- First shower
- Feels like a normal body wash. Patch test first if you have sensitive skin.
- First week
- Use it daily. You'll still sweat, and that's normal and healthy.
- Ongoing
- Results build with consistency. Every shower builds on the last.
On top of odor control
What mandelic acid does for your skin
Smoother skin [3]
Gently exfoliates dead skin cells, the same ones odor bacteria feed on.
Clearer pores [3][4]
Helps unclog pores for smoother, clearer-looking skin on the chest and back.
More even tone [3]
With regular use, helps even the look of skin tone and uneven patches.
Gentle on skin [2]
Well tolerated and gentle enough for daily use, even on sensitive areas.
Body Thesis Lab, and everything else
Body Thesis Lab
Mandelic Acid Body Cleanser
- Addresses the bacteria behind odor
- A single step in the shower
- Free from aluminum, perspiration undisturbed
- The gentlest AHA, kind to sensitive skin
- For the whole body, not only underarms
Everything else
The usual answers
- Deodorants
- Antiperspirants
- Clinical strength
- Natural deodorants
- Body sprays
- Crystals
- Regular soap
- Fragrance that fades as the day goes on
- Aluminum that blocks sweat but leaves bacteria
- Baking soda that can sting or irritate
- Long-hour promises, reapplied by midday
- Made for underarms alone
What dermatologists say about the acid
Independent dermatologists on mandelic acid and odor-causing bacteria
On tolerance
“When we're looking at these acids, I think mandelic acid is probably the one that's the most tolerable.”
Dr. Zakia Rahman
Clinical professor of dermatology · Stanford [1]
On gentleness
Mandelic acid comes with fewer irritating side effects than other AHAs used in conventional products.
Dr. Michele Green
Board-certified cosmetic dermatologist · NYC [2]
On skin benefits
Mandelic acid has antimicrobial, antifungal and anti-inflammatory properties, and is gentle and well tolerated.
Dr. Maya Thosani
Board-certified dermatologist · Scottsdale [2]
On the cause
“The root cause of the smell actually takes the combination of the bacteria and the sweat.”
Dr. Christopher Bunick
Associate professor of dermatology · Yale [1]
On acids and bacteria
On using acids under the arms, it “reduces the bacterial overgrowth in that area.”
Dr. Zakia Rahman
Clinical professor of dermatology · Stanford [1]
On trying acids
“I think it's reasonable to try the acids.”
Dr. Brandon Cohen
Dermatologist · Cedars-Sinai [1]
Statements in quotation marks are exact quotes; others are as reported. Numbers refer to our Sources page.
Make it yours
Select your bundle and request early access. Founding members receive 15% off their first order at launch, at the price shown in your currency. One use per customer, valid for 14 days after launch with the email you sign up with.
For the household
3-bottle bundle
$150.45
$177.00
For a household or every shower. Complimentary shipping.
Request early accessThe 60-day guarantee
We would rather earn your trust than ask for it. Use it daily for up to 60 days. If it isn't right for you, we'll refund you in full.
Frequently asked questions
How is this different from deodorant?
Deodorants mask odor with fragrance. Antiperspirants block sweat glands with aluminum. Formula 003 addresses the bacteria behind odor, at the source.
Will this stop me from sweating?
No, and that's by design. Sweating is how your body cools down. Formula 003 addresses the bacteria that make sweat smell, never the sweat itself.
What is mandelic acid and is it safe for daily use?
Mandelic acid is an alpha hydroxy acid (AHA) derived from bitter almonds. Its larger molecule absorbs slowly, which makes it one of the gentlest AHAs for daily use. Patch test first if you have sensitive skin.
Is there anything I should know before using it?
Sunburn alert: This product contains an alpha hydroxy acid (AHA) that may increase your skin's sensitivity to the sun and particularly the possibility of sunburn. Use a sunscreen, wear protective clothing, and limit sun exposure while using this product and for a week afterwards.
Patch test first: Before your first full use, apply a small amount to the inside of your forearm, leave it for 60 seconds, rinse, and wait 24 hours. If you see redness, itching or swelling, don't use it. Avoid broken, irritated or freshly shaved skin, and stop using it if irritation develops. For external use only. Not for the face or mucous membranes.
Can I use this on my whole body?
Yes. Use it anywhere odor starts: underarms, chest, back, feet and groin. Avoid broken or freshly shaved skin.
Numbers in brackets, like [1], refer to our Sources page. The dermatologists quoted are not affiliated with Body Thesis Lab.
View all sources →The Lab Report
Notes from the lab, product news and first access to new formulations.