My son has had a vitamin D deficiency for years and takes a prescription D 3 supplement (50,000 unit capsule) once each week to maintain a minimum acceptable level.
My son just had his annual check up and his vitamin D was low; he was prescribed a vitamin D supplement (50,000 capsule once a week for 4 weeks).
Same here, my son also has low D and takes the 50,000 unit capsule once a week. He also takes a C and B-12 supplement. I think it all helps.
Mine is low, too. I wear long sleeved shirts to hide the cutting scars on my arms from when I did self-harming, I always wear long pants (just my preference), and I have really long hair, so the sun has a difficult time getting to me. Plus, there’s so many trees here that going for a walk outside you can stay in the shade most of the time anyways.
I take a vitamin D supplement, but still have low D levels.