D has got to be one of the easiest to take. No side effects unless you take a stupid amount. Generally pretty cheap for a large quantity. Numerous studies have linked vitamin D intake to reduced death from all causes. Of course there are some that discount that effect, but it’s not gonna hurt if you do take it. Might want to give it a shot if you aren’t already.
I just started eating more greens and drinking whole milk, as suggested by my doctor because it was just a slight deficiency. I just haven't been to the doctor since to see if it's helping.
Grab the pills when you get a chance. The whole milk only has enough vitamin d to offset the amount used by your body to use the calcium in the milk, so it's net zero additional vitamin d in your diet to drink fortified vitamin D milk. If you're like me, you'll feel a significant difference.
I take a lot of vitamin D, like up to 10,000 IU per day. It’s on the direction of a doctor and my levels get checked several times per year. They (pcp and specialist) never told me to reduce it and afaik it’s caused no problems.