Vitamin D is an essential vitamin produced in the body from direct exposure to sunlight. In response to a health crises in the 1930s related to vitamin D deficiency in children, and because the vitamin is naturally present in few foods, dairy foods and orange juice are now fortified with the micronutrient. Since vitamin D plays a role in helping the body absorb calcium, people who are deficient are at risk for developing soft bones and other conditions that affect muscles and joints.
Muscle Spasm
Muscle spasms, also known as cramps, are characterized by twitching muscles and contractions. Spasms can occur in the hands, feet, digits and even in larger muscle groups. Typically spasms occur only briefly, but they can be severe and painful, according to the University of Maryland Medical Center. Spasms are often caused when the body does not have enough calcium, which is attributed, in part, to a vitamin D deficiency. Other conditions associated with muscle spasms include multiple sclerosis and use of certain medications, both of which are also linked to vitamin D deficiency.
About Vitamin D
Vitamin D is a fat-soluble vitamin stored in fat cells. One of its main responsibilities is to promote the absorption of calcium and enable bone mineralization. Vitamin D sufficiency prevents rickets in children and osteomalacia in adults; both conditions cause softening of the bones and subsequent chronic pain problems. Getting adequate amounts of vitamin D can stave off osteoporosis, a brittle bone disease that can arise later in life and cause frequent fractures. The vitamin also regulates cell growth, neuromuscular function and immune system health. Vitamin D deficiency affects an estimated 30 to 80 percent of Americans, according to Michael Holick, M.D., director of the Bone Health Care Clinic at Boston University Medical Center. Lack of adequate vitamin D is linked to muscle spasms, pain and weakness.
Diagnosing Deficiency
Your doctor can give you a blood test to determine conclusively whether you have low levels of vitamin D. Otherwise, if you get less than 20 minutes of direct sunlight two or three days a week without wearing sunblock, and if you eat few vitamin D-rich foods, you could be deficient. Before taking a vitamin D supplement, talk to your doctor. You could have a condition that interferes with vitamin D absorption.
Considerations
If you're vitamin D deficient, it can take about eight weeks to increase your blood serum levels. You may require a dose that can only be attained through a prescription, according to Holick. The recommended daily allowance of vitamin D is 600 IU for kids and adults and 800 IU for people over the age of 70. It's not unusual for a person who is deficient to take 50,000 IU once a week for eight weeks and then one 50,000 IU supplement every other week. While this may seem high, keep in mind that 20 minutes of direct sunlight produces about 20,000 IU of the vitamin. You can't overdose on vitamin D from the sun, or from food for that matter, because the body has a built-in mechanism for preventing vitamin D toxicity from natural sources, according to the Vitamin D Council.
