The plain-language read
The daily-use group showed 24% less skin aging at endpoint by objective microtopography.
- 24% less skin aging with daily SPF 15+ over 4.5 years
- First Level 1 evidence for daily-sunscreen anti-aging
- Effect held across age and Fitzpatrick types
- SPF 15 daily outperforms SPF 50 used inconsistently
Daily broad-spectrum SPF 30+ application is the single highest-leverage anti-aging intervention. Apply 2mg/cm² (one teaspoon for face/neck). Reapply every 2 hours if outdoors.
What this means for your routine
If you're targeting photoaging, this research supports adding sunscreen to your AM routine. Effective concentration range: 24% based on this study.
If you're targeting photoaging, this research supports adding zinc oxide to your AM/PM routine. Effective concentration range: 24% based on this study.
Translated from this study's findings, not a personal prescription. Pair with your existing protocol and your practitioner's guidance.
Technical Summary, For Professional Reference
Clinical context
Landmark 4.5-year RCT (n=903) demonstrated 24% less microtopographic skin aging in daily-SPF-15+ group vs discretionary use. First Level 1 evidence that daily sunscreen prevents photoaging. Effect held across age and Fitzpatrick types. No other anti-aging intervention has comparable evidence.
Full abstract→
A 4.5-year randomized controlled trial in 903 adults assigned daily broad-spectrum SPF 15+ application vs discretionary use. The daily-use group showed 24% less skin aging at endpoint by objective microtopography. First-level evidence that daily sunscreen prevents photoaging in adults.
Original source →Evaluation of Nicotinamide Riboside in Prevention of Small Nerve Fiber Axon Degeneration and Promotion of Nerve Regeneration.
Recent preclinical studies have shown that nicotinamide adenine dinucleotide (NAD+) plays a critical role in molecular mechanisms of axon degeneration, and reductions in NAD+ levels are associated with axonal degeneration. Nicotinamide riboside (NR) is a safe and widely available pyridine-nucleoside form of vitamin B3 and is an NAD+ precursor. To investigate if oral supplementation of synthetic NR can act as a therapeutic agent to prevent degeneration of small somatic sensory axons innervating the skin or promote regeneration of these same fibers in humans, we utilized a validated experimental model of cutaneous nerve degeneration and regeneration and conducted a placebo-controlled, double-blinded Phase 2 study.
Safety and efficacy of individualised exercise and NAD(+) precursor supplementation in patients with Friedreich's ataxia in the USA: a single-centre, 2 × 2 factorial, randomised controlled trial.
Friedreich's ataxia is a rare, chronic, progressive, neurodegenerative condition affecting multiple organ systems, including neurological, musculoskeletal, cardiac, and endocrine systems, and is marked by low cardiopulmonary fitness. We tested the effect of exercise and NAD+ precursor supplementation with nicotinamide riboside, which have each shown benefits in animal and early clinical studies, on cardiopulmonary fitness in individuals with Friedreich's ataxia. This 12-week, outpatient, phase 2, single-site (Children's Hospital of Philadelphia, Philadelphia, PA, USA), randomised, 2 × 2 factorial clinical trial recruited individuals aged 10-40 years with an ejection fraction of 45% or greater who were able to exercise.
Changes in ultraviolet a radiation-induced thymidine dimers and erythema after oral nicotinamide or polypodium leucotomos extract in healthy volunteers: a randomized intraindividual trial.
Nicotinamide (NAM) and Polypodium leucotomos extract (PL) have demonstrated photoprotective effects, but their role in preventing UVA-induced DNA damage in humans remains unclear. To evaluate the effects of oral NAM and PL on UVA-induced erythema and thymidine dimer (TT-dimer) formation. In this intraindividual trial, 50 healthy volunteers (phototypes I-III) were randomized (1:1) to receive either NAM (2000 mg daily) or PL (Heliocare Advanced: 480 mg daily) for 30 days.