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Algenist Ultra Lightweight UV Defense Fluid SPF 50


4.5 out of 5 stars
  • 5 Stars67%
  • 4 Stars22%
  • 3 Stars8%
  • 2 Stars2%
  • 1 Star1%
4.52 / 5 based on 226 Reviews


An ultra-sheer, weightless fluid for everyday protection against broad-spectrum UVA/UVB damage. This fast-absorbing, ultra-lightweight fluid provides daily protection against broad-spectrum UVA/UVB damage. Alguronic Acid combines with antioxidant-rich botanicals and UVA/UVB protecting actives to delay signs of aging caused by sun and environmental stressors. This oil-free, sheer formula has a silky texture and weightless feel, designed to apply smoothly on top of other skincare products and under makeup for a soft, matte finish. It is formulated Without: - Parabens- Sulfates - Synthetic Dyes- Phthalates- GMOs- Triclosan Alguronic Acid is a unique and powerful regenerative compound from microalgae. This rare ingredient was discovered unexpectedly by a biotechnology laboratory in San Francisco, CA, focused on researching renewable energy solutions. Algenist is the only line of skincare products to contain the antiaging power of Alguronic Acid. Research results:In comparison testing, Alguronic Acid outperformed other well-known active antiaging ingredients, demonstrating superior antiaging benefits: -54% decrease in UV cell damage -55% increase in cellular regeneration -32% increase in elastin synthesis -26% decrease in melanin production *Average results measures following an in-vitro test with Alguronic Acid.

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Algenist Ultra Lightweight UV Defense Fluid SPF 50
Algenist Ultra Lightweight UV Defense Fluid SPF 50
Reviews (226)
Q&A (9)
Media (6)
  • "I absolutely love this moisturizer!  It is so lightweight and it has SPF 50 in it, which is amazing! I always want to make sure I am protecting my skin as well as taking care of it by moisturizing it.  This product does not have a "sunscreen" smell to it either, so it is perfect for everyday use!  It goes really well under makeup as well.  It doesn't all up or anything under makeup.  Great product!!" in 7 reviews
Logan S.
86 reviews
Beauty Junkie Expert Level 2
I cannot rave about this product enough—with a couple of uses this has already became my favorite SPF of all time. Just about every spf I’ve ever used leaves me with a sticky, greasy sheen that reappears no how many times I blot or powder.

Not this one. This is so lightweight that it leaves no remnants that it was even put on. It just sinks right into my skin and leaves no piling or flakes. It also works so well with my makeup routine. I can go as heavy/light as I please and it still holds up.

For reference I have oily skin and I can wear makeup over this and look matte all day, even when in the sun.

It’s $20 something for the smaller size but I’m confident it will last a long time because you don’t need to use much at all.
Talley C.
Augusta, GA
69 reviews
Beauty Junkie Expert Level 1
This sunscreen is absolute perfection. It is SO lightweight. I layer it on top of a serum and my moisturizer and then put makeup on top. Feels like I'm not wearing any sunscreen. The bottle is somewhat small, so when I purchased it I was worried I would run out. But a single bottle has lasted me 3 months and still hasn't run out. Reasonably priced, will absolutely buy again.
Jessica M.
Columbus, OH
175 reviews
Beauty Junkie Expert Level 3
This is my ride or die, holy grail facial sunscreen. I use this every single day under my primer and foundation, or by itself over my regular skincare. I have very oily, acne prone skin, and this product is a godsend. It has a high level of zinc oxide, which is great for clearing up blemishes and protecting from the sun. It goes on kinda white but blends in quickly. It doesn't leave a film on my skin like some sunscreens do. I have used several foundations and primers over this and it plays nicely with them all. My only advice is to do a thorough cleanse at night, because this and other physical sunscreens are harder to wash off. Yoh don't want this to build up in your pores and cause blemishes. An excellent sunscreen for every day.
sarah o.
107 reviews
Beauty Junkie Expert Level 2
For my skin, I use this lightweight sunscreen during the humid spring and summer seasons when I have normal skin. It's very sheer and gives off a matte finish so I reach for this before I run/jog/walk/veg outdoors. In the morning I'll do the 7-skin method with an essence toner, apply a serum, a simple moisturizer, then this sunscreen. Oh don't forget to shake shake shake well :) Goodness, this formula absorbs quickly! So this may be ideal for oily skin folks. But still does the job for my skin while I'm outside working out or running errands. 
Julia P.
114 reviews
Beauty Junkie Expert Level 2
I have oily/combination skin in my 20s. This feels a bit greasy going on but does not look greasy. There isn’t a white cast once you work it into the skin. It provides good protection and wears great under makeup. It did not break me out or irritate my skin.
Rosa d.
122 reviews
Beauty Junkie Expert Level 2
I got this sunscreen/moisturizer in a suncare kit from sephora. I hadn’t had much experience with algenist before, but I was really impressed. The texture is kind of mousse-like, so it goes on really light and fluffy- very impressive considering it’s spf 50!
Anna L.
Suwanee, GA
484 reviews
Beauty Junkie Expert Level 4
Absolutely obsessed with the entire line!!!! I wish the price wasn't so high... but it's so very worth it. I typically order this through Dermstor.com....and I've found it on Amazon as well. The brand is amazing...I've tried a good bit of their products and they all have met or exceeded my expectations. This product included. I'm about to be 31 with an extremely stressful job in an ICU as a nurse...I work 13 hour shifts, get very little sleep, could use some better overall nutrition and in the summer I'm a beach bum sun worshiper...and engine who sees me even with no makeup on would swear to you I couldn't possibly be a day past my mid 20's. 
Kevin Q.
north highlands
43 reviews
Beauty Junkie Expert Level 1
Lightweight protection. I love that this has a super high SPF but doesn’t leave the skin feeling greasy at all. Also has licorice extracts to help brighten the skin. Let’s protect while repairing sun damage. Who wouldn’t want that?
Olivia H.
Murray, UT
10 reviews
Light enough to mix with my moisturizer. Makeup applies well over it, which is nice. It isn’t greasy or heavy and doesn’t have a strong smell. Not particularly affordable, but a little goes a long way, too.
Davia C.
Huntsville, AL
459 reviews
Beauty Junkie Expert Level 5
Love this stuff! I mean the natural occurring collagen sourced from photo-plankton is genius!

Goes on so light and soaks right in! No harsh smells or irritating chemicals!

I noticed a #improvement in #tone #texture #pores #radiance and a reduction of the fine line and wrinkles within my 1st week of using it!

It’s pretty pricey but I cannot live without it!
Jolene K.
70 reviews
What is this? What do you use it for?
Lauren K.
Seneca, SC
242 reviews
Is this okay for faces? I'm always searching for a good sunblock for my face! I have sensitive skin. :(
Rubi S.
238 reviews
I liked this product but too pricey does anyone know any dupes or have other suggestions?
A. N.
217 reviews
Is this very liquidy and does is smell of sunscreen?
Zorimel V.
New Bedford , MA
157 reviews
1 oz seems like an awful small amount. How long does this product usually last for?

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