Energy • causes guide
Low energy in men over 40: common causes
Low energy after 40 is rarely one neat deficiency. It is usually a stack of sleep quality, stress, body-composition changes, low sunlight, poor recovery, diet drift and sometimes a real medical issue.
Highest-probability causes
Poor sleep quality
Fragmented sleep beats total hours when it comes to how you feel the next day.
Stress and over-recovery debt
Chronic stress and thin recovery flatten motivation and energy fast.
Low sunlight and weak vitamin basics
Vitamin D is genuinely relevant for many UK men. B12 and magnesium may matter too, but not in every case.
Medical causes
Sleep apnoea, anaemia, thyroid problems, depression, medication effects and hormone issues need to stay in view.