#1251

No mispeakings, in my opinion, it has been an interesting exchange across different spheres of influence and geographical territories, and that to a significant extent does impinge on skincare practices.
I think that a plausible conclusion is that retinoids do need care in their use, and that with extreme care they might be used everywhere, although extreme care is hard to achieve in very sunny areas.

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#1252

Hi Rose2025, welcome into this forum!

I do take oral astaxanthin plus polypodium, but as a sun protection strategy, unfortunately, the effect does not appear to be significant. Evidently, its protective effect as an antioxidant has little to do with shielding from sun radiation. As you imply, it may even have an inhibitory effect on the melanine pathway.

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#1253

In my case, the topical Azelaic Acid may make a difference. First year of Retin-A use I was diligently avoiding the sun exposure. I did experienced significant peeling of the skin. On my second year, I guess, the body adjusted and now I do not have any of that. The skin on the face still has higher level of desquamation, but it just rubs off, not peels.

Also, if you are interested, the red light irradiation has a sun protective effect. The only thing about it, as with any device, one has to develop a habit to use it on daily basis. :expressionless:

#1254

Welcome! Thanks for chiming in!

You only wear spf on your nose and cheeksā€¦ my vain selfā€™s jaw is on the ground :slight_smile: HA. (I just take vit d and my levels are in the 70ā€™s).

We all have such different genes. Iā€™m someone who needs spf just to have lunch outdoors, otherwise I would resemble a tomato :slight_smile: I also know too many lifelong south Florida women who resemble leather. I imagine you donā€™t see that in the Mediterranean due to different genes, but now Iā€™m curious, do you?

Curious, is there is a reason you use your tret in the morning vs pm? Or perhaps itā€™s only the AA you use in the mornings?

Also, for anyone who is interested, I use the Dermatica tret combined with niacinamide, but they also offer it combined with azelaic acid. I donā€™t have redness/rosacea, so I didnā€™t choose AA, but itā€™s a great combo product for those who need it. Fwiw, they also have one combined with hydroquinone for those who need the big guns.

@mccoy Iā€™m just learning about polypodium for the first timeā€¦ Iā€™d never use it in place of spf, but google says itā€™s interesting. What do you feel the benefits are?
Also, I see it could potentially help vitiligo which a family member hasā€¦ do you know anything about this? Thx

#1255

Two new news items that may be relevant. Fist is a new study out of Japan showing the effects of Vitamin C on skin:

As we age, our skin naturally becomes thinner and more fragile due to a decline in cell production. Now, researchers have found that vitamin C (VC) can help counteract this aging process. Using a 3D human skin model, they showed that VC boosts epidermal thickness by activating genes linked to cell growth through DNA demethylation. These findings suggests that VC may help prevent age-related skin thinning and support healthier, stronger skin in aging individuals.

(Vitamin C has poor skin permeability; but putting some in a solution that includes DMSO might help. Though, I donā€™t know how safe DMSO use is.)

Second is a paper on methods of inducing mammals to regenerate tissue (an ability mammals have lost but that, for example, some amphibians and reptiles have):

Systemically treating mice with retinoic acid boosted ear regeneration. Retinol, on the other hand, did not have that effect, because in retinoic acid synthesis, it lies upstream of ALDH1A2. Conversely, blocking RA synthesis in rabbits impaired their natural ability to regenerate.

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#1256

My personal experience is that it does not provide the protection I hoped, that is, my tolerance to sun radiation is not increased by an amount I can perceive. This fern is however well known for its beneficial effects on the skin. What follows is a description from the Deepseek AI.

Based on current scientific evidence from credible sources (peer-reviewed journals, clinical trials, and reviews), hereā€™s a breakdown of the benefits of Polypodium leucotomos (PL) extract as a supplement, specifically regarding skin protection and vitiligo:

Source Credibility: The information below is primarily drawn from:

  1. Clinical Trials: Published in dermatology journals (e.g., Journal of the American Academy of Dermatology, British Journal of Dermatology).
  2. Systematic Reviews & Meta-Analyses: Summarizing evidence across multiple studies.
  3. Reputable Research Institutions: Studies often conducted at university hospitals and dermatology departments.

Mechanism of Action:
PL is rich in potent phenolic compounds (e.g., chlorogenic acid, ferulic acid, vanillic acid, caffeic acid). Its primary mechanisms relevant to skin include:

  1. Powerful Antioxidant: Scavenges free radicals (ROS) generated by UV radiation and environmental stressors.
  2. Anti-inflammatory: Inhibits pro-inflammatory pathways (e.g., NF-kB, COX-2) and reduces cytokine release.
  3. Immunomodulatory: Modulates immune responses in the skin.
  4. DNA Photoprotection: May help protect against UV-induced DNA damage.
  5. Inhibition of MMPs: Reduces UV-induced matrix metalloproteinases (MMPs) that break down collagen, contributing to photoaging.

Benefits for General Skin Protection:

  1. Photoprotection (Internal Sunscreen Adjuvant):

    • Increases MED (Minimal Erythema Dose): Multiple studies show oral PL significantly increases the amount of UV radiation needed to cause sunburn (erythema). This means it provides systemic protection from within, making skin more resilient to sun damage. (Sources: GonzĆ”lez et al., J Am Acad Dermatol 2008; Middelkamp-Hup et al., J Am Acad Dermatol 2004).
    • Reduces UV-Induced Damage: Protects against UV-induced cell death (apoptosis), DNA damage (as measured by reduced cyclobutane pyrimidine dimers - CPDs), lipid peroxidation, and Langerhans cell depletion. (Sources: Nestor et al., J Clin Aesthet Dermatol 2014; Philips et al., Photodermatol Photoimmunol Photomed 2009).
    • Improves Skin Barrier: Some evidence suggests it may help strengthen the skin barrier against environmental insults.

  2. Anti-Photoaging:

    • By reducing oxidative stress, inflammation, and MMP activity induced by UV, PL helps prevent collagen degradation and the formation of wrinkles and solar elastosis associated with premature aging. (Sources: Kohli et al., J Drugs Dermatol 2020).

  3. Protection Against Hyperpigmentation:

    • While less studied than photoprotection, its antioxidant and anti-inflammatory effects likely help mitigate UV-induced melanogenesis (pigment production), potentially reducing the risk of sun spots (solar lentigines) and melasma exacerbation. It may also help stabilize active melasma.

Benefits for Vitiligo:

PL has shown significant promise as an adjunctive therapy for vitiligo, particularly in stabilizing active disease and enhancing the effects of phototherapy:

  1. Stabilizes Active Vitiligo:

    • Studies demonstrate that oral PL can help halt the progression of actively spreading (unstable) vitiligo. It reduces the appearance of new lesions and slows the expansion of existing ones. (Sources: Parsad et al., Br J Dermatol 2015; Middelkamp-Hup et al., J Eur Acad Dermatol Venereol 2007).

  2. Enhances Efficacy of Phototherapy (NB-UVB):

    • When combined with Narrowband Ultraviolet B (NB-UVB) phototherapy ā€“ the gold standard treatment for vitiligo ā€“ PL significantly improves repigmentation outcomes compared to NB-UVB alone.
    • Patients achieve repigmentation faster and to a greater extent (higher percentage of body surface area repigmented). (Sources: Parsad et al., Br J Dermatol 2015; Reyes et al., Int J Dermatol 2006).
    • It may allow for lower cumulative UV doses to achieve results, potentially improving the safety profile of long-term phototherapy.

  3. Reduces Phototherapy Side Effects:

    • By acting as a systemic photoprotectant, PL helps reduce the erythema (redness) and burning sometimes associated with NB-UVB therapy, improving patient tolerance. (Source: Middelkamp-Hup et al., J Eur Acad Dermatol Venereol 2007).

  4. Mechanism in Vitiligo:

    • Likely involves its potent antioxidant action (counteracting oxidative stress implicated in melanocyte damage/death in vitiligo), anti-inflammatory effects (modulating the autoimmune/inflammatory component), and potential immunomodulatory properties. It may also protect remaining melanocytes and melanocyte precursors during phototherapy.

Safety & Dosing:

  • Safety: Generally well-tolerated in clinical studies. Mild gastrointestinal upset (e.g., stomach ache, nausea) is the most commonly reported side effect, occurring infrequently. Long-term safety data is still evolving but appears favorable. (Source: Nestor et al., J Clin Aesthet Dermatol 2014).
  • Dosing (Typical Ranges in Studies):
    • Photoprotection/General: 240-480 mg per day (often divided into two doses).
    • Vitiligo (Adjuvant to NB-UVB): 250-500 mg twice daily (500-1000 mg total per day). Dosing often starts a few weeks before initiating phototherapy.

Important Considerations & Limitations:

  1. Not a Sunscreen Replacement: PL provides systemic photoprotection but DOES NOT block UV rays like topical sunscreen. It should be used IN ADDITION TO rigorous sun protection (broad-spectrum SPF 30+, hats, shade), not as a substitute. It makes skin more resilient from the inside.
  2. Adjunctive Therapy for Vitiligo: PL is not a cure for vitiligo. It is most effective as an add-on treatment, primarily to stabilize active disease and enhance the results of NB-UVB phototherapy. Results vary between individuals.
  3. Quality Matters: Supplements are not strictly regulated. Choose reputable brands that specify the extract source and standardized content (e.g., FernblockĀ® is a well-studied proprietary extract).
  4. Consult a Doctor/Dermatologist: Essential before starting PL, especially for vitiligo management. They can confirm the diagnosis, assess disease activity, recommend appropriate primary treatments (like NB-UVB), advise on suitability/dosing of PL, and monitor progress and potential interactions with other medications.

Conclusion:

Scientific evidence supports Polypodium leucotomos extract as a beneficial oral supplement for skin health:

  • For General Skin Protection: It acts as a potent systemic antioxidant and anti-inflammatory agent, significantly increasing the skinā€™s resilience to UV damage (reducing sunburn, DNA damage, photoaging) when used alongside topical sunscreen.
  • For Vitiligo: It is a valuable adjunctive therapy, particularly effective in stabilizing actively spreading vitiligo and significantly enhancing the speed and degree of repigmentation achieved with NB-UVB phototherapy, while also reducing phototherapy-related side effects.

Consistent use and combination with standard protective measures (sunscreen) or treatments (phototherapy) are key to seeing benefits. Always consult a healthcare professional before use.

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#1257

Sorry to mislead you. I mentioned AA in the morning, that is true, and you guessed it right - I apply Retin-A at night as many do.
Skin sensitivity may also depend on the skin type. My is Fitzpatrick III. It must be different for I and II. They are more photosensitive. Besides after years of using Retin-A the structure of the skin changes. It is possible that with a prolonged use the RA affects melanocytes too by inhibiting their mobility.

I definitely do not look that those Florida women ā€œrode hard put away wetā€ā€¦I am originally from FL, so I know what you are talking about. There are some of those types here too. Mediterranean climate is more comfortable and no fire antsā€¦lol

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