Siim Land recommends five specific supplements (collagen peptides, astaxanthin, hyaluronic acid, glycine, and niacinamide) to support skin health and combat skin aging.

noli's read

Science supports the idea that these compounds play a role in skin physiology, although the strength of the evidence varies. Collagen peptides are supported by meta-analyses showing moderate improvement in skin elasticity and hydration in adults. Astaxanthin, a potent antioxidant, shows promising results in randomized controlled trials (RCTs) for protection against UV-induced damage, though the magnitude of this effect remains debated. Oral hyaluronic acid is supported by studies suggesting improved hydration, although bioavailability is a subject of ongoing study. Glycine is a key precursor to collagen, and studies suggest it may limit damage related to glycation (the 'caramelization' of proteins), a process linked to aging. Finally, niacinamide (vitamin B3) is recognized for supporting DNA repair and cellular energy production (NAD), although its topical use is often better documented than its oral use for specific skin benefits. Overall, these supplements target real biological mechanisms, but they do not replace adequate sun protection or a balanced overall diet.

the sources

No named source held this one up — that absence is part of the verdict.