Vitamin D Your Sunshine

New Research Shows Vitamin D is Lacking for Many
Our bodies can make vitamin D3 only when our skin is exposed to sunlight under the proper conditions. This production is dependant on the season, where we live and time of day. People with darkly pigmented skin living in northern or southern latitudes have lower synthesis compared to fair skin people. Sunscreen with a sun protection factor (SPF) of 8, reduces the production of vitamin D3 by over 95%. During late autumn through winter, little or no vitamin D can be produced by sun exposure at latitudes above 35 degrees north latitude which runs through the middle of the United States.

When days become shorter and with the passing of the fall equinox, supplemental vitamin D is increasingly important for many people. Vitamin D is vital for many functions in our bodies, and higher blood concentrations of vitamin D are now associated with good health and strong bodies. Yet many people do not obtain optimal levels of vitamin D, especially in the winter months when the sun is low in the sky.

Sunshine Can Produce 10,000 IU

However, our evolution has designed us to live in the presence of far more vitamin D than most of us receive now. Our ancestors had far greater sun exposure compared to many of us who cover up most of our skin surface or use sunblock. Studies indicate that one full-body exposure to sunlight (enough time to just start to sunburn) can be equivalent to an oral vitamin D intake of 10,000 IU (250 mcg).

Vitamin D in Few Foods
For those people with limited sun exposure, optimal vitamin D must be obtained from dietary supplements or foods. Unfortunately, vitamin D is found naturally in very few foods. These foods include some fatty fish (herring, salmon, sardines), fish liver oils, and eggs from hens that have been fed vitamin D. In the U.S., milk and infant formula are fortified with vitamin D to contain 10 mcg (400 IU) per quart. However, other dairy products such as cheese and yogurt are not usually fortified with vitamin D.

More Functions Discovered
Research now indicates that vitamin D receptors are found throughout our body and that vitamin D may have even broader functions than generally established in the field of nutrition. It not only helps to build strong bones, but adequate vitamin D may prevent some tooth loss, help with muscle strength including our heart muscle, and help with our ability to fight infection. Another important research finding is that we may need more vitamin D than current recommendations.

Promotes Bone and Muscle Strength

Clinical Studies indicate that supplemental vitamin D is effective in reducing fractures (broken bones), improving bone density and improving muscle strength.

Widespread deficiencies of vitamin D may play a big role in causing the bone-wasting disease osteoporosis among older Americans. Calcium and vitamin D are integral to bone health. Low levels of vitamin D have also been associated with muscle weakness, muscle pain and poor coordination. Increased risk of fractures because of low vitamin D status is attributed to muscle weakness, poor coordination, and also to osteoporosis. In clinical studies, the use of 800 to 1,000 IU per day of supplemental vitamin D along with calcium has been helpful in reducing fractures, improving bone density and improving muscle strength. These improvements are especially important because the lifelong risk of suffering a fracture due to osteoporosis has been estimated at 50%. Combined calcium and vitamin D supplemention is effective, safe and inexpensive for people at risk for osteoporotic fractures.

Supplemental vitamin D reduces risk of fractures.

A group of 2,686 people aged 65-85 living in the general community was assigned to receive 4 monthly 100,000 IU doses of vitamin D3 supplement or a placebo during the winter months. [This amount averages about 800 IU of vitamin D daily.] The group receiving the supplemental vitamin D had a reduced risk of 22% for sustaining a first general fracture and a 33% reduced risk for sustaining a first fracture of common osteopathic sites.

Supplemental vitamin D improves muscle strength and reduced fractures.

A group of 122 women (average age 85) were observed for six weeks prior to receiving either 1,200 mg of calcium daily or 1,200 mg of calcium and 800 IU of vitamin D daily for 12 weeks. Muscle strength increased only in the group receiving both calcium and vitamin D. This group also had a 49% reduction in falls. Researchers theorized that vitamin D increases calcium flow in the muscle tissue, which improves contraction, thus preventing falls.

Hip fracture risk was reduced by 69% and secondary hyperparathyroidism was reversed with supplemental vitamin D.

In a study with 583 elderly women (mean age 85 years), those given 1200 mg of calcium and 800 IU of vitamin D had a 69% reduced risk of suffering a hip fracture. Their parathyroid hormone levels returned to the normal range after 6 months of treatment and, bone density (femoral neck) measurements in the treatment group remained unchanged indicating that further bone loss was prevented.

Almost all patients with persistent muscle and bone pain were vitamin D deficient.

Researchers at a primary care clinic in Minneapolis, Minnesota tested blood levels of patients with persistent general pain in their bones and muscles. They found that 93% of the 150 patients were vitamin D deficient. Bone thinning, which results from vitamin D deficiency, is known to cause such pain. The researchers recommend that all outpatients with musculoskeletal pain be screened for vitamin D deficiency.