Self-administered daytime light supplementation in older adults: randomised study
In a randomised study with 202 adults aged 63–92 in three EU cities, participants self-implemented indoor light supplementation for 12 weeks; the abstract reports associations between naturalistic light exposure and activity, wakefulness, sleep quality and metabolic disorder incidence. [1]
Automatic summary · not editorially reviewed
The key findings
Controlled studies show light supplementation benefits circadian entrainment, sleep and mood, but real-world use is shaped by habits and environmental light. [1]
202 adults aged 63–92 in three EU cities were randomised to 12 weeks of self-implemented indoor light supplementation (N=98) or no intervention. [1]
Greater naturalistic light exposure was associated with more daytime activity, consolidated wakefulness, better subjective sleep quality and reduced metabolic disorder incidence. [1]
The source at a glance
- Study type / format
- Interventional, prospective, randomised study (abstract).
- Population / context
- Adults aged 63–92 (139 women) in Amsterdam, Bologna and Tartu.
- Summary based on
- Study abstract
- Original publication
- September 1, 2026
Older urban adults and self-directed light use
The authors note that controlled studies show light supplementation benefits circadian entrainment, sleep and mood, but real-world use is shaped by personal habits and environmental light. They focus on older adults because reduced ocular light sensitivity with natural ageing worsens low daytime indoor light in urban housing. They therefore studied what determines self-directed light supplementation and its real-world feasibility and efficacy.
Supporting source [1]
Randomised lamp group versus no intervention
202 participants (63–92 years; 139 women) in Amsterdam, Bologna and Tartu had a 2-week baseline of light exposure, rest-activity patterns and sleep via wearables and diaries. They were then randomised to 12 weeks of self-implemented indoor light supplementation with a lamp in their most-used room (>8000 melanopic EDI, N=98) or to a no-intervention group. A 2-week reassessment followed.
Supporting source [1]
Associations with activity, sleep and metabolism
The reassessment showed that greater naturalistic light exposure was associated with increased daytime activity, consolidated wakefulness, better subjective sleep quality and reduced metabolic disorder incidence. People with lower naturalistic light exposure started indoor supplementation earlier and for longer across seasons; onset before 10:00 was associated with greater daytime activity and lower rest-activity fragmentation. These are associations, not proven causes, and the abstract does not report effect sizes or between-group results.
Supporting source [1]
How to interpret this
Abstract only; the full text was not reviewed. The abstract reports associations without effect sizes or between-group comparisons, and the authors' conclusion about broad potential is their interpretation, not a demonstrated causal benefit.
Based on the study abstract; the full paper, tables and supplementary data were not reviewed.
Source & supporting passages
Constantino DB, Baccari F, Caporali L, Carelli V, Amore G, Gordijn M, Haller T, Morgia C, Landvreugd A, Marinelli M, McDaid D, Nõmm M, Nonino F, Romagnoli M, Schettino M, Zenesini C, Bartels M, Skene DJ, van der Veen DR. · europepmc.org · September 1, 2026