Vitamin D3 deficiency is a very serious condition, although it is not discussed very often. You receive this vitamin primarily from exposure to the sun. You don't need to be outside that much, but getting sunlight every day is important to maintaining your D3 levels. And it's not as if failing to go outside will simple make you pale: Rather, a D3 deficiency can have serious consequences, ranging from osteoporosis to cancer. Luckily, there are symptoms you can pay attention to early on to make sure these more dangerous conditions don't present themselves.
.High Blood Pressure
If you don't get enough vitamin D3 in your system, you can develop high blood pressure, which wreaks havoc on your health and could shorten your life if not properly controlled. If you have high blood pressure, schedule some time out in the sun to make sure that your body can absorb both vitamin D and calcium properly.
Depression
Feeling depressed is another possible symptom of a vitamin D3 deficiency. A lack of sunlight can negatively impact your mood, making you feel down and hopeless, even if you're in a good position in your life.
Fatigue and Weakness
Along with depression, chronic fatigue is another symptom of a lack of vitamin D3. Without this essential vitamin, you'll feel drained and lethargic--as if even the simplest of tasks is just too much to handle. Related conditions like fibromyalgia can also occur, and your muscles can feel weak and strained.
Rickets
Your body needs vitamin D3 to allow for proper calcium absorption. This vitamin is also a hormone and actually binds with calcium, helping it to be absorbed into the body more easily. Without enough D3, you won't absorb enough calcium. And without enough calcium, you could develop rickets, a condition that results in softening of the bones. (However, it primarily affects children.)
Bone Pain
A lack of vitamin D3 can also cause severe bone pain, especially at the joints where the muscles connect to the bones. This can be debilitating; see your doctor right away to receive an accurate diagnosis and treatment plan.
Symptoms of Low Vitamin D3 | eHow.com