The Regimen

Thick or Thin: What’s the Correct Consistency of a Serum?

Two Vivant Skin Care serums, studio photo


Serums are the workhorses of your regimen and the mainstay of the Vivant line. A glance through the reviews on our product pages reveals customers and aestheticians find our serums truly rave-worthy. But now and again we get a question about the runny consistency. Why can’t we make them thicker, so they’re easier to apply? So many reasons. Let’s unpack.


The point of serums is to deliver transformative ingredients to the deeper levels of the skin where they can work their magic. To do that, they need to be lightweight, easily absorbed, and ultra-efficient.



When is a Serum Not a Serum?

Though you will see them labeled as serums, a thicker formula is not a serum. It’s a lotion or cream. And, while lotions and creams can carry beneficial ingredients, they don’t work the way that a serum does.


The big difference between a true serum and a cream or lotion is what’s left out. To be effective, a serum should not contain occlusive or emollient ingredients. No thickening agents or fillers. Nothing to get in the way of active ingredients and keep them from reaching the dermis.


What a serum should contain is targeted, pure ingredients—antioxidants, peptides, acids, brighteners, cell regenerators—in super-concentrated doses that can be easily infused into the skin.


These actives are more expensive than thickeners and emollients, so while serums tend to be more expensive ounce per ounce, you’re getting more for your money. And because the ingredients are distilled to their most potent form, you only need to use a very small amount with each application.



How to Apply Serum

Cleanse and tone your skin before applying your serum to remove dirt, makeup, oil, and dead skin cells, and clear the way for optimum absorption of your serum.


 The eye dropper applicator is designed to help you manage the application process more easily.


Pro tip for applying: put four drops on the TOP of your hand (not the palm). Dab the fingertips of your other hand in the serum and apply to face, neck, and décolleté, rubbing gently. Rub the tops of your hands together, so you don’t waste a molecule. (Rejuv Rx is too thin for this approach. Put that one in the palm of your hand.)


If you use a moisturizer, apply it after the serum. Give the serum a few minutes to dry before applying moisturizer.


If you’ve ever seen the advice to add a few drops of serum to your moisturizer and apply it that way, don’t. For all the reasons mentioned above. 


If you’re using more than one serum, layer them by weight with the lightest being first. We know they’re all lightweight, but there are very subtle differences. For instance, our Vitamin A serums are more viscous than our Rejuv Rx Peptide Concentrate. Derm-A-Renew and Bleaching Cream have the heaviest consistency of our serums.



What Should You Look for in a Serum?

Acne-prone: Look for vitamin A (accelerates cell turnover, unclogs pores), glycolic acid (exfoliates and brightens), salicylic acid (reduces inflammation, flushes pores), mandelic acid (kills acne bacteria, gently exfoliates, brightens), niacinamide (strengthens skin barrier), zinc (soothes irritation, regulates oil production).


Try Exfol-A if acne is the main concern (best for skin already acclimated to vitamin A). For acne in sensitive or hyperpigmentation-prone skin, try 8% Mandelic Acid 3-In-1 Serum.


Aging: Look for vitamin A (antioxidant, accelerates cell renewal, reduces lines and wrinkles), lactic acid (gently exfoliates, hydrates, softens), kojic acid (brightens), peptides (boosts collagen and elastin, reduces redness).


Try Derm-A Renew Peptide and Vitamin A Serum


Photo-damage or dullness: Look for vitamin C (antioxidant, increases collagen production, brightens, protects against UV damage) and vitamin E (enhances cellular repair, reduces inflammation) to boost sun protection by day, and promote brightening and repair by night.


Try Spin Trap Antioxidant Vitamin C & E Therapy.


Dry or Rosacea: Look for peptides (increase elasticity, boost collagen, reduce redness), niacinamide (improves skin elasticity, increases ceramide levels in skin), lactic acid (gently exfoliates, draws in and retains moisture).


Try Rejuv Rx Peptide Concentrate.


Hyperpigmentation: Look for mandelic acid (antioxidant, inhibits melanin production, brightens, reduces inflammation), lactic acid (gentle exfoliates, draws and retains moisture), vitamin C (protects against UV damage, brightens), niacinamide (suppresses melanin, reduces inflammation, improves skin barrier), or hydroquinone (inhibits melanin production, breaks down excess pigment) .


Try 15% Mandelic Acid 3-In-1 Serum (best for skin already acclimated to mandelic acid). For more severe pigmentation issues, try Bleaching Cream.



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