Expert: Vitamin D as important as calcium in fighting osteoporosis

CEBU, Philippines - In the fight against osteoporosis, calcium has become the star and Vitamin D has remained the unsung hero.

“After we started our information campaign on osteoporosis in 1998, public awareness on the importance of calcium in bone health increased significantly. Unfortunately, the same cannot be said about Vitamin D,” says Professor Leilani B. Mercado-Asis, MD, PhD, President of the Osteoporosis Society of the Philippines and Secretary of the Philippine Society of Endocrinology and Metabolism.

Vitamin D vital for calcium absorption

Why worry about low public awareness on Vitamin D? The prevalence of Vitamin D deficiency in postmenopausal Asian women is 71 percent, reveals Asis. “Vitamin D deficiency magnifies the threat of osteoporosis. Without sufficient levels of the vitamin, the body won’t be able to efficiently absorb calcium which is crucial for maintaining bone density and strength.”

Asis points out that female gender and menopause are non-modifiable osteoporosis risk factors. Eighty percent of people with osteoporosis are women. “Before menopause, women have a steady supply of estrogen which holds back a type of bone cell called osteoclasts from breaking down bones. With the onset of menopause, estrogen levels drop and these destructive ‘Pacman cells’ are no longer restrained from eating up bone,” explains Asis.

Postmenopausal women are particularly at risk for Vitamin D deficiency because they often have little or no exposure to sunlight and inadequate intake of calcium-rich foods. Moreover, skin levels of Vitamin D and the skin’s ability to manufacture the vitamin diminish with age.

The Vitamin D precursor present in skin requires sunlight to be converted to its active form, explains Asis. “That’s why we need to get early-morning sun exposure for 30 minutes every day. This is sensible sun exposure.” According to Asis, our modern lifestyle, inordinate fear of skin cancer and the “white is beautiful” fad hyped by skin-whitening products have conspired to “demonize” sun exposure. “We ride in our tinted cars to go to our air-conditioned and shuttered offices where we work the entire day. It seems we’ve become afraid of the sun.”

Elderly at risk for falls, fractures

The aging Filipino population also worries Asis. “This year, the number of Filipinos aged 65 years and older is estimated to be a little under 4 million; by 2040, this figure is expected to balloon to almost 14 million. That’s a lot of people at risk for osteoporosis and the falls and fractures associated with the bone-thinning disease.”

Each year, 1 in 3 individuals 65 years of age or older suffer a fall. The elderly are particularly prone to falls because many of them take a variety of medicines for diseases and conditions that develop with age. Some of these medicines (sedatives and blood pressure drugs, in particular) can cause dizziness, lightheadedness, or loss of balance. Moreover, elderly people are at increased risk of falls because of diminished vision, hearing, muscle strength, coordination, reflexes, as well as diseases that affect balance. The elderly are especially vulnerable to bone fractures because many of them have osteoporosis, which makes their bones more fragile and easily broken.

“Aside from ensuring optimal absorption of calcium, Vitamin D also stabilizes nerves that keep reflexes intact, which helps a person maintain balance and prevent falls that can lead to fractures,” Asis says. Studies indicate that calcium combined with Vitamin D supplementation can reduce the risk of fracture in men and women over the age of 65. Studies also show that calcium plus Vitamin D increases muscle strength and reduces the frequency of falls among the elderly.

Calcium and Vitamin D: Foundation for osteoporosis prevention

Asis cited the updated guidelines of the US National Osteoporosis Foundation (NOF recommending that adults under 50 years of age get 400-800 International Units (IU) of Vitamin D daily while adults 50 and over get 800-1000 IU of Vitamin D daily. Pregnant and lactating women should get 1000-1200 IU of Vitamin D, she noted.

“Bone health consciousness and osteoporosis prevention should start as early as when a baby is still in the mother’s womb,” Asis says. A pregnant woman should have sufficient calcium and vitamin D intake. Mothers should encourage their children to drink milk until adulthood and regularly eat calcium-rich foods, like green leafy vegetables. They should also promote an active lifestyle among their children because regular exercise and physical activity help build strong bones.

“People need to know that osteoporosis can be prevented, and the foundation of osteoporosis prevention is adequate levels of calcium and vitamin D,” stresses Asis. But if osteoporosis develops, she continues, there are treatment options available. “Alendronate is a type of medicine that acts like estrogen. It stops ‘Pacman cells’ from eating up bone.” Asis notes that a medication combining bisphosphonate and Vitamin D would benefit postmenopausal women with osteoporosis. “It would help patients comply with their treatment regimen.”

Alendronate 70mg + Vitamin D (cholecalciferol) 5600 IU is a product of research-based pharmaceutical company Merck Sharp & Dohme (MSD). It is a medicine that can only be bought with a prescription and should be taken only upon the advice of a physician.