Vitamin D Toxicity
Having sufficient vitamin D levels would help boost the immune system and protect the body against cancer or osteoporosis. Nevertheless, there is no agreement on an optimal range, which may be between 40 to 80 ng/ml. When people take in more than 100 ng/ml per day, it may be harmful and lead to vitamin D toxicity. Common problems with this condition include slurred speech, vomiting, nausea, forgetfulness, and extreme fatigue. Fortunately, this side effect only occurs when only extremely large doses are taken. Make sure to consult your doctor before deciding to take any vitamin D supplements. [5]
Bone Issues
Though a sufficient intake of vitamin D is important for bone health, taking in too much would actually cause a reverse effect. Some studies have suggested that high levels of vitamin D may reduce levels of vitamin K2. This nutrient plays a role in maintaining calcium in the bones and keeping calcium out of the blood. As a result, an excessive amount of vitamin D would lead to bone loss and increase the risk of bone fractures. [6]
