Vitamin D is crucial to bone health and also helps to regulate your immune system. Your body normally makes vitamin D by synthesizing sunlight through specialized cells in your skin. Individuals who live in northern climates do not get as much sunlight and may need to take supplements to get enough vitamin D. Vitamin D supplements can cause stomach upset in some individuals. Additionally, taking more than the tolerable upper intake can also cause stomach cramping.
Take your supplement with food. Taking a supplement on an empty stomach increases your chance of stomach upset.
Reduce your dosage. The National Institutes of Health recommends no more than 1,000 IU daily for children under age 12 and 2,000 IU daily for individuals over age 12. If you are taking close to this amount, reduce your dosage to the recommended minimum – 200 IU for adults under 50 and children, 400 IU for adults ages 51 to 70, and 600 IU for adults over 70.
Increase your intake of foods that contain vitamin D to offset the reduced supplement amounts. Naturally occurring vitamin D will be less likely to cause a stomach ache. Food sources include fatty fish such as salmon or tuna; eggs, and foods fortified with vitamin D, such as milk.
Gradually increase the dose by 100 IU each week until you reach the maximum or experience stomach upset. A gradual increase allows your stomach to adjust to the vitamin D and may prevent stomach upset.
Stop taking vitamin D and consult your physician immediately if you experience severe stomach pain, excessive thirst and a metal taste in your mouth. Those symptoms, in addition to bone pain and muscle problems, could indicate toxicity.