Vit d 6.84 ng/ml, can cause only legweaknes(on and off) low energy(on and off), hairloss. so low vit d causes any other symptoms? is sunlight enough?

This level is low!: This vitamin d level is very low. Vitamin d not only helps your body absorb calcium much better, it also affects your muscle and core strength. We don't recommend spending too much time getting sunlight as as the primary source of vitamin d, due to the risk of skin cancer! see your doctor for a temporary high dose of vitamin d to 'catch you up', then take 1000-2000 units of vitamin d3 daily.