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Supplement · Photoprotection · Astaxanthin

P. 06 · BRIEF

Astaxanthin.

Carotenoid antioxidant with replicated elasticity and MED data.

— § 01

The brief.

Class
Carotenoid (xanthophyll)
Source
Haematococcus pluvialis (natural)
Dose
4 – 12 mg/d with food
Timeline
9 – 12 weeks for effect
Pregnancy
Insufficient data — defer
Interactions
Mild antiplatelet at high dose
Reviewer
Dr. Paul · 17-Apr-2026
⁂

— § 02

What the literature shows.

UV-induced erythema
RCTs vs placebo

Modest reduction in MED at 4–6 mg/d after 9 weeks. Not a sunscreen replacement.

62%
Skin elasticity
RCTs, 4–12 mg/d

Replicated bioengineering improvement; visible benefit modest.

55%
Hydration / TEWL
Bioengineering

Statistically real, clinically subtle.

48%
Wrinkle reduction
12-wk RCTs

Some signal; not the headline most marketing implies.

40%
⁂

— § 03

On our shelf.

⁂

— § 04

Frequently asked.

Does it actually 'replace' sunscreen?

No, and any marketing that implies so is misleading. Oral astaxanthin produces a modest reduction in UV-induced erythema after 6–9 weeks, on the order of 10–20% — useful as an adjunct, useless as a substitute.

Natural or synthetic?

Natural Haematococcus-derived astaxanthin has the bulk of the published in-vivo skin data. Synthetic astaxanthin (used in aquaculture) is structurally similar but its published clinical data is thinner. Spend the small premium for the natural form.

Is it safe long-term?

Yes — well-tolerated up to 12 mg/d in trials lasting 6 months. Mild stool-orange discoloration possible at high doses (it is a carotenoid).

Will it interact with anything?

Mild blood-thinning effect at high doses. If you are on warfarin or DOACs, mention to your doctor before starting.