Home / News & advice / Light & Health
Does sunlight help you lose weight?
What a research on fat cells teaches us, and why it does not justify further exposure to the sun.
The essential benchmarks
What to remember
A study in mice showed that some fat cells react to light. This discovery does not demonstrate that sunbathing is a loss of weight, nor that light can replace nutritional management in humans.
What does this discovery really show?
Researchers have investigated OPN3, a light-sensitive protein present in fat cells of mice. In their experiments, this mechanism was involved in mobilizing the fat needed to produce heat when animals were exposed to cold.
The subject is interesting: it shows that the relationship between our luminous environment and biology does not only go through vision. However, a mechanism observed in the laboratory must be distinguished from a treatment that can be used in the practice.
Does the sun help to lose weight?
This work does not allow you to prescribe a duration of exposure, a lamp or a tanning session to lose weight. Nor do they establish that the lack of light alone explains an increase in weight.
If your weight changes, the starting point remains your situation: diet, activity, sleep, current treatments and history. The same steps are not chosen for recent weight gain, postmenopausal change or old difficulty.
Enjoy from the outside by protecting your skin
A walk can be an opportunity to move and get out of your home, without trying to sunbathe. Prefer shade and times where the radiation is less intense. In the metropolis, avoid exposure between noon and 4 p.m. in summer.
Clothing, a hat and glasses are the first protections. A sunscreen SPF 50 protecting UVA and UVB completes them on the discovered areas, with regular renewal. A diet rich in carotenoids or a "solar" supplement does not replace these protections.
When can I ask for an accompaniment?
You can consult if you want to understand weight gain or find a food organization compatible with your daily life. Prepare some simple benchmarks: weight changes, usual meal schedules, activity and questions you want to address.
Page weight loss and nutrition present the accompaniment. The consultation rates are grouped on the dedicated page.
A question about your situation? The practice welcomes you to 4 Passage Lonjon, Place de la Comédie in Montpellier.
Contact the practiceMedical sources and information
- Nayak et al. — Cell Reports, 2020: Experimental study in mice
- National Cancer Institute — Protecting from the Sun
Updated on 20 October 2026. The information presented makes it possible to prepare the consultation; the choices of care are specified during the appointment.