I would like to see more studies regarding this before jumping to any conclusions.
It defies reason that simply looking at a screen, as opposed to doing something else sedentary, would have such a profound effect.
For now I'll continue to eat healthy and exercise 4-5 times a week. I also routinely hit my 10,000 step target just by walking to / from parking at work as well as random stuff throughout the day. Honestly I'm not that worried.
You're thinking about it wrong.
Blue light does affect your circadian rhythm. This is completely sound science based on numerous findings.
Alterations in circadian rhythms such as genetic manipulations, inverted light periods, "jet lag" (increased length of one period compared to another for a short amount of time) and chemical manipulations all affect physiology. Again, there are mountains of evidence that this is true.
Physiology can be affected multiple, subtle ways. Example:
Dampened circadian rhythms cause insulin resistance and diabetes, non-alcoholic fatty liver disease, hepatocarcinoma, depression and weight gain. All of these are not just correlations, but also have mechanistic corroborations. However, many of the studies are
done in mice. That is not to say that they're not relevant to humans, the contrary, most have been backed up in human studies, despite it being very difficult to keep people on a fixed circadian schedule, showing the robustness of these findings. However, mice don't think about their health. They live to eat, and if they're lucky, fuck.
In terms of the effects, all these changes on the hormonal, cellular and molecular level do indeed occur, they make you eat worse by increasing your appetite, increasing your desire for sugary and fatty foods, they cause increased accumulation of fat, decreased insulin resistance and increased glucose in the blood (etc, etc I don't want to name all the effects), however some of these effects can be counteracted by diet and exercise.
There's again, a mountain of evidence to show that AMPK activation, the "energy sensing protein", which becomes activated by exercise or calorie restriction can counteract many of these effects. While not necessarily tested in all the permutations of circadian disruption, AMPK is the master protein of regulating energy metabolism, so a logical extrapolation that it protects from other forms of circadian disruption.
