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  • General questions

    Posted by luukheum on October 2, 2017 at 11:25 pm

    Hi there,

    Lately I gathered a few questions, and for most of them I had a hard time finding reliable information on the internet. For some of them I just didn’t know what to search for, they’re probably easy to answer. Anyways, I didn’t want to create different topics for these somewhat general questions. Hope you might be able to help out. Thank you!

    1. Do most popular skincare functional ingredients possibly actually increase aging? As I understand, Vitamin C, n-acetyl Glucosamine, niacinamide etcetera lighten your skin by decreasing melanin content in your skin. Melanin is the protection mechanism of your skin to prevent UV damage. I can’t find any research on this topic! Possibly those ingredients might have some short-term positive effects, and could be used for aesthetic reasons. But isn’t it plausible there are negative effects long term, because pigmentation is decreased? https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2671032/

    2. In this articles it is proposed that using niacinamide increases unnecessary gene expression, and thus possibly increasing aging of the skin long-term. Would you recommend to stop using niacinamide as a precaution? https://www.futurederm.com/why-you-should-use-niacinamide-only-with-resveratrol/

    3. How do oils, for example grapeseed oil, make your skin soft? Is it only the moisturizing effect/TEWL or is something other at play as well? If not, vaseline should make skin more soft than oil. In other words only more water makes the skin soft?

    4. If I put petrolatum on at night, wash it off in the morning, how long will the benefits last? A couple hours, days? Would an added moisturizer with some emollients in the morning help (squalene and glycerin for example)? I know the effect is temporary, and probably won’t do that much for skin longterm. But I’m actually interested in this very temporary improvement. Also how long should petrolatum be on my skin for maximum effect, does it matter much?

    5. To me all moisturizers look the same really about 30 minutes after applying, given they are not too oily. Not talking about texture or feeling or active ingredients - just looks; my skin does not look better. I doubt there is any difference at all. I can’t find any research or pictures or comparisons. Strange though in a multi-billion dollar business! Would this mean that, in other words, the only visible difference might be the amount of water retained in the skin; the TEWL rating of an ingredient and the reflective properties of the ingredients on skin ? Is this the whole story in terms of the so called ‘skin glow’ people talk about? If so, then the perfect ingredient/moisturizer will have

    - the highest TEWL block rating

    - but be mostly absorbed/evaporated in a maximum of about 30 minutes, because longer would not be desireable since one does not want to look oily

    This would therefore exclude petroleum jelly etcetera. Does anything fit these requirements being the ultimate moisturizer, the one you slap on before big events; weddings/going out/any moment you want to look your best? Maybe dimethicone or will silicones look too shiny on skin?

    6. I’m using a DIY ascorbic acid, in a plastic 12mL spray. I make a new one every week. Will buying a glass bottle or airless dispenser improve my recipe in theory?

    7. Proper shaving soap should really only do two things:
    * lubricate skin so that the razor bumps less into skin thus creating less cuts
    * soften hair so the razors cuts more smoothly through the hair thus creating less cuts (speed differences will create more razors cuts)

    I would like to leave cleansing and moisturizing and soothing irritation out of the equation, since I prefer to do this with separate products. Does somebody know which two ingredients would be most successful? Soap might be too harsh, so curious to know if there’s any alternative!

    Thanks in advance.


    DRBOB@VERDIENT.BIZ replied 6 years, 2 months ago 4 Members · 4 Replies
  • 4 Replies
  • zaidjeber

    October 3, 2017 at 6:10 am

    @luukheum I
    will try to answer your 1st question.

    UVA & UVB are the most common rays that affect our skin.
    UVB has short wave length and it can reach the outer layer of our skin, the
    epidermis, whilst UVA has longer wave length that can penetrate deeper and
    reach the dermis. 

    Now UV through photo-oxidation triggers the production of ROS
    (Reactive Oxygen Species) or free radicals which in turn triggers the
    production of melanin to protect our skin against UV damage.  

    The antioxidants (skincare functional) like vitamin C will
    neutralizes those free radicals and temporarily decreases the production of the
    skin melanin so the skin appears brighter/ lighter. At the same time, the
    antioxidants will protect the skin from photo-oxidation damage aka aging effect
    again via free radicals neutralization effect.

    I hope its clear enough and answers your question.  

  • luukheum

    October 3, 2017 at 10:39 am

    @zaidjeber I actually do understand how vitamin c is supposed to work. But what I don’t know is: how much will the lower melanin concentration increase photosensitivity of the skin? And will this counter the positive effects of vitamin c?

    Besides, the positive effects are only there for as long as vitamin c is applied, the lower melanin concentration is more lasting.
  • oldperry

    October 3, 2017 at 2:28 pm

    @luukheum - These aren’t exactly general questions and each one should really be a discussion by themselves.  Here are some quick answers. If you want a more thorough discussion of any of them, make it a separate discussion.

    1.  No, there is no evidence they increase aging. There is little evidence they decrease aging either. Most of these ingredients as used in cosmetics are marketing stories only.

    2.  This is an unproven hypothesis. 

    3.  Oils don’t actually moisturize. The are nonpolar and they blend with the nonpolar elements of the outer skin. They soften but only have minimal moisturizing effects. Petrolatum actually creates a barrier film which doesn’t allow water to escape the skin. This causes a build-up in the outer layers of skin and is responsible for the moisturization effect. 

    4.  A couple hours.  What do you want the squalene to help with?  Maximum effect of petrolatum would depend on many factors including the condition of your own skin, your genetics, the environment surrounding you, your heart rate, level of moisture, etc. There are too many factors to give an answer. Generally, leaving it on longer will have a greater effect until you reach the maximum which I would guess would vary from 30 min to a few hours.

    5.  There are only slight differences. The effectiveness of a moisturizer depends on your skin. There is no perfect ingredient/moisturizer. Petrolatum scores highest for TEWL

    6.  Maybe. But it’s unlikely you’d notice any difference.

    7.  I shave with warm water which works fine enough for me. It’s really a personal preference.


    October 3, 2017 at 3:05 pm

    Question 1 There is sufficient evidence to show antioxidants such VC help slow the aging process via inhibition of ROS so benefits outweigh all other negative considerations.

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