It’s the season of shortening days and early nighttime. For those of us in the Pacific Northwest, rain further darkens our days.
The change in seasons brings a nutrient concern for many of us. Are we getting enough sunlight for our bodies to make the vitamin D we need?
In this article, we illuminate the significance of vitamin D for bone and muscle health and offer ways to get enough of this essential nutrient.
Concerning Prevalence of Vitamin D Deficiencies
Vitamin D deficiency is extremely common and increasing. A National Institutes of Health (NIH) survey finds that about 42% of Americans are vitamin D deficient, with much higher rates of deficiency among minority groups with darker skin tones.
People at highest risk include people with darker skin tones, pregnant and breastfeeding women, people over 65 (because their skin isn’t as good at making vitamin D), and babies and young children, especially if they don’t play outside often. Health issues like Crohn’s, celiac disease, liver disease, and kidney disease can also reduce the amount of vitamin D the body makes. Certain medications can also reduce vitamin D production.
We rely on ultraviolet rays from sunlight to produce the vitamin D our bodies need for healthy bones, muscles, and immune function. However, people living above the 37th parallel – a horizontal line across the US from San Franscico to Richmond, VA at 37 degrees north – can only get enough sunlight in summer months. Even then, the sunscreen that protects our skin blocks these ultraviolet rays.
Vitamin D is Vital to Calcium Absorption
When we’re lacking vitamin D, we might feel tired, depressed, or suffer from bone and muscle aches and cramps. A severe lack of vitamin D in children can also cause muscle spasms, an early sign of rickets. Muscle and bone pain can also indicate a lack of calcium, another serious concern.
Without enough vitamin D, our bodies can’t absorb and retain calcium, the main building block of our teeth and bones. Calcium is vital to blood clotting and muscle contractions, including our heart beating. We lose calcium through sweat, urine, feces, and our skin, hair, and nails. The body doesn’t produce calcium, so we must get it through our diets or supplementation.
When we lack vitamin D and calcium as children or as adults, our risk of osteoporosis greatly increases. Our bone tissue is continually dissolving and being replaced with new tissue. Calcium is crucial to this rebuilding process. With osteoporosis, new bone formation doesn’t keep up with bone tissue loss.
When there is not enough calcium in the bloodstream, our bodies may take it from the skeleton. This can result in thin, brittle bones and irreversible osteoporosis. It’s even more imperative that people with osteoporosis get enough vitamin D and calcium or bones will continue to lose strength.
Amounts of Vitamin D and Calcium We Need
How much vitamin D and calcium do we need? People with diseases like Crohn’s (and the others listed above) or who’ve had gastric bypass surgery often need higher amounts, but the minimum recommendations for calcium are:
- Children and adults age 50 or younger – 1,000 mgs
- Adults age 50 or older – 1,200 mgs
Many of us can get enough calcium from dairy, seeds, greens, beans, and fortified foods. Vitamin D is found in fewer foods. The best sources of vitamin D are fatty fish, mushrooms, and fortified foods.
The optimal amounts of vitamin D we need are under review, but the minimums recommended in the US are:
- Children 12 months and younger – 400 IUs
- Children age 1-18 – 600 IUs
- Adults age 19-70 – 600 IUs
- Adults age 70 and older – 800 IUs
Higher Amounts of Vitamin D Are Safe
Health experts recommend we expose our skin to 10-15 minutes of sunlight daily whenever possible. They also recommend vitamin D supplementation for children and adults to assure we get adequate amounts of both nutrients throughout life.
Studies continue on the maximum amounts we can take without concern of toxicity. The NIH says these amounts are safe:
- Children 0-6 months old – 1,000 IUs
- Children 7-12 months old – 1,500 IUs
- Children 1-3 years old – 2,500 IUs
- Children 4-8 years old – 3,000 IUs
- Children 9-18 years old – 4,000 IUs
- Adults – 4,000 IUs
It's recommended that we have our blood vitamin D concentrations checked regularly. Pediatricians recommend vitamin D supplements for babies who are breast fed, or paritial breast fed. Adults may also need vitamin D or calcium supplements.
Adults can get a blend of stomach-friendly calcium, vitamin D, and magnesium from Cal-Mag Complex to help assure the health of bones, muscles, nerves, the heart, and the immune system.