YES- highly advised. The average multivitamin has 400 iu of vitamin d. Many experts feel it is optimal to achieve a vitamin d level of at least 45 ng/dl. Most adults need to take 4000-5000 units a day to achieve these levels, so taking 4000-5000 units plus a multivitamin is wise. Toxicity won't occur with 10, 000 units or less/day. See http://www. Huffingtonpost. Com/dr-mark-hyman/vitamin-d-why-you-are-pro_b_585311.Html.
Working nightshifts (hence, no sunlight/asleep during daytime). Should I take vitamin d supplements and at what dosage?
Get lab. You might be vitamin d deficient but before taking a supplement, get a level checked first so you can know how much to take. It will also serve as a baseline level to know if you have improved on the replacement. 2000-4000 iu/day vit d3 is a standard and safe level but monitoring is very important.
Do cold hands and feet mean a weak immune system? I take vitamin d supplements and eat relatively healthy. Or likely something else?
Unlikely. Cold hands and feet do not a poor immune system. It may be a thyroid issue, it may be a circulation issue but I doubt as you are quite young to have a circulation problem... It may just be you with no cause.
Depends on dosage. That depends on the dosage that it says to take.
No. Taking calcium and vit. D will make your bones stronger but height is a genetic trait.
Not at all. Growing taller requires open growth centers in your bones. The hormones that sustain growth, increase in puberty for a final push, but also signal the growth centers to close. This occurs from 16-20 in most males and 15-17 in most females. Once the growth centers close, no supplement. Special diet, exercise or anything else will increase your height. At a listed age of 38, you are finished growing.