UF Researcher Finds Vitamins, Regular Exercise And Weight Training May Improve Bone Density Without Hormone Therapy
GAINESVILLE, Fla. — As the debate over the safety of hormone replacement therapy continues, University of Florida nurse researchers have shown in a small but promising study that a combination of vitamin supplements, exercise and weight training may provide postmenopausal women an alternate way to improve bone health and prevent osteoporosis.
In a UF study of postmenopausal women who were not taking hormone replacement therapy, those who participated in a regular exercise regimen that included weight training and took vitamin D and calcium showed significant improvements in bone density, strength and balance.
A growing body of evidence supports the benefits of exercise for the prevention of bone loss that commonly occurs with aging, but the latest findings are among the first to show exercise that includes resistance training can actually build bone-a result hormones have never achieved. Results from the preliminary study are described in the current issue of the journal Biological Research for Nursing.
“Vitamin D and calcium supplements can help slow down the loss of bone, and most hormone treatments can only stop future bone loss,” said James Jessup, the study’s principal investigator and an associate professor in UF’s College of Nursing who also is affiliated with UF’s Institute on Aging. “There is no drug out there that can cause the kind of improvement in bone density that was displayed in the research participants.”
Although the study was small, Jessup said the results are promising and likely will lead to expanded research efforts aimed at finding ways to improve bone health in postmenopausal women without the use of hormones.
UF researchers studied 20 healthy women ages 60 to 75 who lived in a community retirement facility. Half were randomly assigned to a group who exercised routinely and half to a control group who did not. Past scientific research has shown physical activity can improve balance, but to stimulate bone formation, resistance must be used in combination with exercise. Therefore, the exercisers wore weighted vests while doing cardiovascular exercise.
All the study’s participants maintained their usual eating habits and were supplied with and asked to take 1,000 milligrams of calcium citrate malate, the full U.S. recommended daily allowance for adult women, and 400 international units of vitamin D, twice the U.S. R.D.A. Past research has shown that supplements of calcium and vitamin D can reduce bone loss and the risk of fractures in older people.
In the women who exercised over a 32-week period, bone mineral density increased an average of 11 percent, as seen on X-ray imaging. In addition, their strength increased 26 percent, and their balance increased 27 percent. The women participated in supervised calisthenics, strength training, walking and stair climbing for 60 to 90 minutes three times a week. This included working with weight machines, and engaging in balance and agility training. The bone density of the women not participating in exercise actually decreased an average of 5 percent, and strength and balance did not change.
“Women now are living longer than ever before, which means more women will experience the long-term effects of menopause,” Jessup said. “These results suggest that there is an alternative for health maintenance and osteoporosis prevention without the inherent risks and adverse effects of hormones. These exercises also aid in overall strength and physical functioning, balance, blood pressure and body weight – all important components of maintaining independence.”
Hormone replacement therapy inhibits bone loss and decreases the risk of fractures. But this past July, the National Institutes of Health’s Women’s Health Initiative halted a study of more than 16,000 healthy postmenopausal women who were taking a form of hormone replacement therapy after they were judged to be at increased risk of heart attack, stroke, breast cancer and blood clots. Osteoporosis medications have been shown to effectively treat the condition, but they also can cause adverse effects such as nausea and abdominal pain.
The effects of bone loss occur more rapidly in women than in men because of a decline in estrogen levels that occurs after menopause. In the United States, one in every two women older than 50 will suffer an osteoporosis-related fracture in her lifetime. Falls in the home resulting from a loss of balance are the most common cause of fractures in older adults, Jessup said. There is substantial evidence, however, that much of the decline in balance is not the direct result of aging but stems from the lack of physical activity associated with a sedentary lifestyle.
Before beginning the study, Jessup and his research team measured participants’ initial bone mineral density, strength and balance, and assessed their confidence in their ability to participate in physical activity. Both groups showed almost identical characteristics before the study began, although those in the group who didn’t exercise had, on average, slightly higher bone mineral density. None of the 20 had participated in a regular exercise regimen in the past 12 months.
Exercise group participants also lost an average of 5 pounds, and their systolic blood pressure decreased 10 percent. Although researchers expected improvement, they had no idea how significant the results would be, Jessup said. In fact, most participants continued with the exercise regimen after the study concluded.
Having worked a full-time job most of her life, study participant Judith Cohen, 70, had never found much time to exercise. The years of work had taken their toll on her body, she said.
“I had aches from head to toe, and my hip was in constant pain,” Cohen said. “After participating in Dr. Jessup’s exercise regimen, the pain began to go away, and my hip fell back into place. I feel extraordinary.”
After Cohen went through menopause, her doctor prescribed hormone replacement therapy and osteoporosis medications, but the side effects made her ill, so she refused to continue treatment, she said.
“Menopause is not a disease, and we shouldn’t treat it like one,” Jessup said.
The study was an initial pilot study of the UF College of Nursing’s Biobehavioral Research Center, which is funded by a $670,000 grant from the National Institute for Nursing Research, part of the National Institutes of Health. Because the study was small, Jessup plans to duplicate it on a much larger scale.
“Elderly people often suffer from reduced bone mass and a greater propensity to fall down and hurt themselves,” said Charles H. Turner, director of orthopaedic research and a professor of orthopaedic surgery and biomedical engineering at the Indiana University School of Medicine. “Proper exercise may help to avoid both of these problems and provide a drug-free alternative osteoporosis therapy.”