Taking too much vitamin D can harm your body. Here are some possible harms:

1. High blood calcium: Too much vitamin D can make your blood calcium level rise, causing nausea, vomiting, constipation, weakness, and increased thirst. Sometimes, it can lead to serious health problems.

2. Kidney problems: Having too much vitamin D can increase the chance of getting kidney stones and damage. It can cause calcium to build up in your urine, leading to stone formation and difficulty passing them.

3. Digestive issues: Taking excessive vitamin D can result in digestive problems like nausea, constipation, diarrhea, and stomach pain.

4. Nervous system damage: Consuming too much vitamin D can harm your nervous system, causing tiredness, weakness, headaches, dizziness, and cramps.

5. Negative effect on bones: Consuming excess vitamin D may make calcium deposit in muscle tissue instead of bones. This raises the risk of fractures and affects overall bone health.

Remember, these risks come from taking too much vitamin D. It's safe and necessary to have moderate and recommended levels of vitamin D for a healthy body. If you think you lack vitamin D or want to take supplements, consult a doctor to find the correct dose based on your health.