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Before You Buy Another Firming Serum: 6 Things Most Women Over 40 Miss
Most of us buy firming serum on a whim. An ad follows you around for a week and another pretty bottle lands on the bathroom shelf. I went through a whole cabinet of them in my late forties before I worked out what to look at first.
The one I kept using was the Vitro EGF NAD+ Firming Serum, a small red dropper bottle that passes every check on this list.
You put serum on your face twice a day for months, so it's worth two minutes of checking before you pay. These six checks are what finally stopped me wasting money on bottles that ended up half full at the back of the cabinet.

1. Turn the Box Over Before You Pay
Every serum box has an ingredient list on the back, and it is the most honest part of the packaging. If it runs to forty lines and you can't tell which one is supposed to do the work, put the box back.
Vitro's list is seven ingredients long: Aqua, Glycerin, 1,2-Hexanediol, Carbomer, Arginine, Nicotinamide Adenine Dinucleotide and Collagen Extract. Nicotinamide Adenine Dinucleotide is NAD+ written out in full.
Once I started reading the back first, I put a lot of bottles back on the shelf.
“I've tried a lot of serums that promised the world. With this one my skin felt softer by the end of the first week, and I've kept going.”
Diane M.

2. If It Sits on Your Skin for Ten Minutes, You'll Stop Using It
A serum only helps if you keep using it. If it's still tacky by the time you reach for your moisturizer, or it pills up under makeup, that bottle won't get finished.
With Vitro you smooth three or four drops over your face and neck and massage them in until they're gone. Glycerin pulls water into the skin and holds it there, and in Vitro's consumer self-assessment study, people reported a 36.8% improvement in skin hydration after the first application.
By the time I've screwed the dropper back on, it has sunk in, and my moisturizer goes straight on top.
3–4 drops · Face and neck · Morning and night
“Vitro's NAD+ Serum smoothed my crow's feet, plumped my eyes, and gave my skin a glow. I love how it absorbs instantly and starts working fast.”
Rachel D. · Verified buyer

3. Stop at Your Jawline and You've Skipped Half the Job
My neck started looking older than my face somewhere around 48, and the only thing it ever got from me was sunscreen, and not often.
Vitro's directions say face and neck, and the formula carries Collagen Extract for skin that has lost some of its bounce. In the same study, people reported a 33.1% improvement in skin elasticity and firmness after two weeks.
I save one drop for my neck and smooth it upward from the collarbone. It adds about ten seconds.
“I do my neck every night with whatever is left on my fingers, and the skin under my chin looks smoother.”
Carol W.

4. If It Adds Three Steps to Your Morning, It'll Be in the Drawer by Friday
If a serum needs a toner first and a five-minute wait before anything else goes on, it won't make it through a busy week.
Vitro is one step. Cleanse, three or four drops, done. Use it as the last step of your routine or layer it with the serums you already own, morning and night.
“My expensive skincare routine stopped working, so I tried Vitro. My skin looks amazing. The wrinkles I was noticing have visibly softened and my complexion looks so much better.”
Jenna K. · Verified buyer

5. Give It Four Weeks Before You Decide
Firmness and fine lines take two to four weeks to show a visible change, so write the start date on the box and hold off judging until then.
Many people notice softer, more hydrated skin in the first week. In Vitro's study, people reported a 29.4% visible reduction in fine lines and wrinkles, 27.6% smoother texture and a 24.9% improvement in radiance after two weeks.
I took a photo by the kitchen window on day one and another at week four. That second photo is the reason I reordered.
“My under eyes are so smooth and my skin feels firmer while staying hydrated. Easy to apply and absorbs in seconds. Will never go without this serum.”
Maya S. · Verified buyer

6. Order From the Brand's Own Site, and Nowhere Else
Vitro has sold out more than once, and the brand asks people to buy only from its official site. That is the one place you can be sure you're getting the genuine formula.
Orders there are processed in two days, then take 6–12 business days to arrive, tracked the whole way. Shipping is free over $50, and support answers at support@tryvitro.com, Monday to Friday, 9 to 5 Eastern.
I'm on my third bottle now.
“Took about two weeks to get here, but I could track it the whole way. My skin looks smoother and I'm already on my second bottle.”
Lorraine B.
1. Turn the Box Over Before You Pay

Every serum box has an ingredient list on the back, and it is the most honest part of the packaging. If it runs to forty lines and you can't tell which one is supposed to do the work, put the box back.
Vitro's list is seven ingredients long: Aqua, Glycerin, 1,2-Hexanediol, Carbomer, Arginine, Nicotinamide Adenine Dinucleotide and Collagen Extract. Nicotinamide Adenine Dinucleotide is NAD+ written out in full.
Once I started reading the back first, I put a lot of bottles back on the shelf.
“I've tried a lot of serums that promised the world. With this one my skin felt softer by the end of the first week, and I've kept going.”
Diane M.
2. If It Sits on Your Skin for Ten Minutes, You'll Stop Using It

A serum only helps if you keep using it. If it's still tacky by the time you reach for your moisturizer, or it pills up under makeup, that bottle won't get finished.
With Vitro you smooth three or four drops over your face and neck and massage them in until they're gone. Glycerin pulls water into the skin and holds it there, and in Vitro's consumer self-assessment study, people reported a 36.8% improvement in skin hydration after the first application.
By the time I've screwed the dropper back on, it has sunk in, and my moisturizer goes straight on top.
3–4 drops · Face and neck · Morning and night
“Vitro's NAD+ Serum smoothed my crow's feet, plumped my eyes, and gave my skin a glow. I love how it absorbs instantly and starts working fast.”
Rachel D. · Verified buyer
3. Stop at Your Jawline and You've Skipped Half the Job

My neck started looking older than my face somewhere around 48, and the only thing it ever got from me was sunscreen, and not often.
Vitro's directions say face and neck, and the formula carries Collagen Extract for skin that has lost some of its bounce. In the same study, people reported a 33.1% improvement in skin elasticity and firmness after two weeks.
I save one drop for my neck and smooth it upward from the collarbone. It adds about ten seconds.
“I do my neck every night with whatever is left on my fingers, and the skin under my chin looks smoother.”
Carol W.
4. If It Adds Three Steps to Your Morning, It'll Be in the Drawer by Friday

If a serum needs a toner first and a five-minute wait before anything else goes on, it won't make it through a busy week.
Vitro is one step. Cleanse, three or four drops, done. Use it as the last step of your routine or layer it with the serums you already own, morning and night.
“My expensive skincare routine stopped working, so I tried Vitro. My skin looks amazing. The wrinkles I was noticing have visibly softened and my complexion looks so much better.”
Jenna K. · Verified buyer
5. Give It Four Weeks Before You Decide

Firmness and fine lines take two to four weeks to show a visible change, so write the start date on the box and hold off judging until then.
Many people notice softer, more hydrated skin in the first week. In Vitro's study, people reported a 29.4% visible reduction in fine lines and wrinkles, 27.6% smoother texture and a 24.9% improvement in radiance after two weeks.
I took a photo by the kitchen window on day one and another at week four. That second photo is the reason I reordered.
“My under eyes are so smooth and my skin feels firmer while staying hydrated. Easy to apply and absorbs in seconds. Will never go without this serum.”
Maya S. · Verified buyer

Rated 4.8/5.0 · Excellent
The Vitro EGF NAD+ Firming Serum
7-Ingredient Formula · NAD+, Glycerin and Collagen Extract
3–4 Drops · Face and Neck, Morning and Night
One Step · Last in Your Routine, or Layered
Free Shipping Over $50 · 6–12 Business Days After Processing
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This page is an advertisement for the Vitro EGF NAD+ Firming Serum. Study figures come from Vitro's consumer self-assessment study. Results may vary. Questions: support@tryvitro.com
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