- Low sunlight could cause SAD (https://www.mayoclinic.org/diseases-conditions/seasonal-affe...)
- Depending on how you exercise, if you go very hard at the gym, you can start off with high energy when you start but as you build a routine and ramp up in intensity/volume, you will end up very tired
- Your cortisol levels could be high from working too much/boredom. I think a lot of people might be confusing depression with general boredom/overwork (https://health.clevelandclinic.org/effects-of-working-too-mu...) and often, a solution would be moderate exercise to increase dopamine production or planning going to some big event (I personally really look forward to electronic music festivals/events)
- Over/under weight can cause low energy. What's your diet like?
- Is your sleep optimal? You might have sleep apnea or some sleep conditions that you might want to look into
In general, I found when I was eating healthy, going to the gym moderately, and had an active healthy social life, my energy levels were mostly good compared to when I was working really hard, not really going out, and exercising. It's probably multi-faceted and you'll have to double check your assessment of you being tired as actually physically tired, or unmotivated/bored.
After 30 my energy to food consumption ratio began digressing. The American diet is shit. We eat and eat and eat and our bodies STARVE for nutrition. I discovered and started taking Healthforce Vitagreen every day (at least one liquid diet meal per day.) this very expensive yet well worth it item is equivalent to a heaping big portion of greens in a water soluble scoop (an effective soylent green!)
A few years later again my food to energy ratio begins to plummet (digestion just takes longer, feels heavier, and does not produce the energy of my youth.) So I’ve added GNC 1340 high calorie powder to my daily liquid diet (which until then was mostly vitagreen and a protein mix.)
I EXTOL THE POWER OF PURE CALORIES!
Unfortunately, you’ll still need solid foods in there from time to time.
When I have the high calorie additive and go through a day without exercise, I feel like I have jumping beans in my blood lying awake at night. Have to do some pushups just to fall asleep.
- Get an OGTT and fasting insulin and see if your HOMA-IR, fasting glucose, or postload glucose aren't in prediabetic ranges.
- Check your iron, B9, B12, vitamin D levels and remember that a lot of people are basically functionally deficient when in the lower part of the reference range.
- Try keeping indoor CO2 levels low, breaking sitting up with brief physical activity, and consider light therapy glasses. Lack of all three substantially contributes to fatigue. Prolonged sitting straight up reduces brain volume over years.
Past that, do you have any symptoms, however small that could give a hint as to what might be going on? Dizzyness when getting up, cold hands and feet, gastrointestinal symptoms or excess gassiness, anything at all?