The utility of light is not just to aid in vision. According to Dr Vassily Eliopoulos, light also provides metabolic information. Taking to Instagram on July 7, Dr Vass stated metabolism is not just about what we eat. What we see and we we see it matters just as much.It is healthy to experinece sunlight within the first hour of waking up. (Pexel)Also Read | Did you know some people get itchy when they exercise? Dr Kunal Sood explains why that happensAs per the physician, the body uses light as a timing signal to regulate metabolism, hormones, appetite, and energy. This means that light tells the body:When to burn fatWhen to spike insulinWhen to sleep, eat, move, and recoverThe wrong light at the wrong time can therefore leave our cells confused. He went on to explain how the system works, which is presented as follows.Benefits of morning sunlightDr Vass claimed morning sunlight to be “metabolic gold.” According to the physician, early sunlight helps:Set your circadian rhythmBoost cortisol (in a good way)Regulate insulin sensitivitySynchronise appetite and fat-burning signalsDrawbacks of bright light at nightAccording to Dr Vass, bright light at night signals blood sugar disruption. Exposure to blue light in particular, which is radiated from smartphone and computer screens, has the following effects:Inhibits melatoninReduces glucose tolerance by up to 50%Increases late-night cravingsCircadian mismatch leads to insulin resistanceExposure to light at the wrong time affects the circadian rhythm, which is the internal, biological clock within the body. As per Dr Vass, the internal clock being out of sync with light/dark cycles can have the following effects:Fat storage increasesMetabolism slowsHunger hormones go haywire“This happens with late nights, night shift work, and too much screen time,” noted the physician. He observed that people who work night shifts are at especially high metabolic risk. For them, being exposed to blue light is not optional.As such, night shift workers commonly have:25-40 percent higher rates of obesity and type 2 diabetesDisrupted melatonin and leptinMore visceral fatHow to align the circadian rhythm with lightDr Vass suggested trying the following to get the internal circadian rhythm in sync with external light.Get five to 10 minutes of sunlight within 60 minutes of wakingDim screens and lights one to two hours before bedUse warm light at night (up to 2700K)Try blue-light blockers after sunsetSleep in a fully dark room (blackout shades or mask)“Light is a metabolic signal, not just a visual one. Your cells are listening,” he added. “Align your light with your biology and watch your energy, blood sugar, sleep, and cravings reset.”Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.This report is based on user-generated content from social media. HT.com has not independently verified the claims and does not endorse them.Dr Vassily Eliopoulos, popularly known as Dr Vass on social media, is a longevity expert trained at Cornell University and co-founder and chief medical officer of Longevity Health.