This CNN story reports on a study of flashing light therapy as a method to improve the body’s ability to respond to jet lag. While it was an admittedly brief study with few participants, there was sufficient detail to suggest that the flashing light might be more beneficial compared to continuous light as a countermeasure for jet lag. But the story doesn’t do much to evaluate the qualify of evidence on offer here. Including at least one outside expert as a source, as a competing Reuters story did, and mention of other techniques that have undergone research to counter jet lag (melatonin, caffeine), would have been helpful.
Jet lag is a significant concern for many people who have to travel distances that span multiple time zones, where their ability to work effectively is compromised as the body struggles to adjust to a new time zone. This means a simple, but effective light therapy session could bring much-needed relief to those who have to travel but also, possibly to those who do shift work and are frequently forced into combat against the body’s natural circadian rhythms. People who work in demanding jobs where alertness and quick adaptability to changing sleep schedules are required (airline pilots, doctors, nurses, ambulance attendants, truck drivers, etc.) may benefit from such a therapy.
Costs are not discussed. How much would a device that emits a flashing light that delivers a camera-like flash every ten or so seconds cost? It could be a little or a lot, depending on the purchaser. The competing Reuters story at least suggested that this device would require complicated new technology that one can presume might be costly.
Details on the benefits are minimal but we do get a sense that two different groups of volunteers were tested with different light exposures (continuous vs. intermittent flashing) and those with the intermittent flashing light had “two hours of change in circadian timing, compared with 36 minutes for those exposed to continuous light.” Changes in “circadian timing” is not explained.
There were no harms expressed in the article, nor was the word ‘harm’ mentioned in the published study. This is where an outside expert may have shined some light. As an expert quoted in a Reuters article stated, “Mistiming light therapy can make jet lag worse.”
It is impossible to tell from the article how sound the study was. In fact, the study, although preliminary, was a randomized, controlled trial which raises the level of evidence for the findings. This was not mentioned. The article doesn’t point out until the last sentence that “There’s still more testing to be done before the technique is available to the public.”
There is no obvious disease mongering here and jet lag is a common problem with likely serious consequences for some professions.
No outside expert was asked to comment and cast a critical eye on the quality of the evidence and the soundness of the study.
Jet lag has been studied with other therapies, most notably with caffeine and melatonin. Neither of these other therapies are mentioned in the context of describing this study. Cochrane systematic reviews on jet lag therapies can be found here and here.
This report doesn’t suggest any comparison between the light therapy and these other therapies.
The story mentions that the light therapy wasn’t ready for prime time yet.
The article notes that the current study builds on the team’s previous “proof-of-principle” research that suggested exposure to light at night speeds up time zone adjustment. The latest study found short light flashes had an advantage over continuous light exposure. There is no misleading representation as to the technique’s novelty.
Despite its reliance on one source, it doesn’t appear as if the article is overly indebted to a PR news release. The article contains quotes from the study co-author that are different than those found in the release.