There are other ways to keep bones strong
She’s never broken a bone. And, at 61, her bones are as strong as those of a healthy woman half her age, according to her bone density scan. Rudloff, who has a master’s degree in holistic nutrition, attributes that to a lifetime of physical activity and eating vegetables.
The Bend, Ore., resident is not a rigid anti-dairy person, but she does not believe in the prevailing wisdom that drinking milk is the key to strong bones.
Osteoporosis can lead to serious or debilitating fractures, especially when it comes to the hips and spine.
It’s a bone disease characterized by decreased bone mass and poor bone quality that affects more than 200 million people worldwide and some 10 million people in the U.S., according to the American Academy of Orthopaedic Surgeons.
Women experience osteoporosis at a significantly higher rate than men, and it is most prevalent post-menopause.
Calcium and its partner in absorption, vitamin D, are major components of bone health. Milk contains both.
But to many people, drinking more milk, or eating dairy food derivatives of it, is not the singular solution to the osteoporosis problem. There’s contradiction within various health-related communities about many aspects of the milk question. And there’s conflicting research on the topic. Some suggests that milk doesn’t help much at all.
Higher consumption of milk by adult women did not protect against bone fractures, according to a 12-year study published in the American Journal of Public Health in 1997 in which researchers followed 78,000 women to determine whether higher intake of milk and other calcium-rich foods during the adult years could reduce the risk of bone fractures.
A similar large, long-term study in the American Journal of Clinical Nutrition in 2003 reiterated that neither milk nor a high-calcium diet reduced the risk of hip fractures. The study added, however, that consuming adequate amounts of vitamin D was associated with a lower risk of fracture.
Other studies have suggested that people in the countries that consume the most meat and milk — namely the United States and Scandinavian countries — also had the highest rates of osteoporosis.
But observational dietary studies are imperfect and hard to draw conclusions from, said Connie Weaver, a national spokeswoman for the American Society for Nutrition. Besides, plenty of studies say just the opposite, said Weaver, also a professor and head of the Department of Nutrition Science at Purdue University in Indiana.
Overriding the dietary calcium question, she said, is the prominent role our genes play.
“Bone mass relates to fracture risk. Your bone mass is about 60 percent controlled by genetics,” said Weaver. The other 40 percent, roughly, is controlled by environmental factors such as diet and lifestyle, which individuals have some control over.
“Some people have genes that give you high bone mass. There’s little you can do to screw that up,” she said.
There are a couple of considerations when trying to consume adequate calcium, Weaver said.
One is the quantity of calcium that exists within a food.
The other is bioavailability, or how efficiently that calcium is absorbed, said Weaver, who has been involved with clinical studies about calcium absorption.
Calcium’s bioavailability, or absorption rate, is better in green leafy vegetables such as broccoli and kale, than in dairy products. But there’s less of a concentration of calcium in vegetables and legumes compared to milk. So, a person would have to eat enormous amounts of vegetables to absorb the same amount as they could from a smaller quantity of milk.
The Physicians Committee for Responsible Medicine, a Washington, D.C.-based nonprofit that advocates for preventive health and good nutrition, said on its website that “The calcium absorption from vegetables is as good or better than that of milk. Calcium absorption from milk is approximately 32 percent. Figures for broccoli, Brussels sprouts, mustard greens, turnip greens, and kale range between 40-64 percent.”
That is true, Weaver said, but is misleading since it doesn’t address how much higher in concentration calcium is in milk.
Weaver said it’s nearly impossible to consume the daily recommended amounts of calcium from food in the absence of dairy products. And Carroll said cow’s milk is the best source of calcium for Americans because it’s affordable and accessible.
The U.S. Department of Agriculture recommends most Americans drink three glasses of milk daily. That’s not just about calcium, said Weaver. Milk contains other nutrients that are vital to bone and tissue health, including potassium, magnesium, phosphorous, vitamin A and vitamin D.
Osteoporosis is less a condition of inadequate calcium intake and more the result of too much calcium loss, said Lisa Gladden, a primary care nurse practitioner at Mosaic Medical in Bend.
There are many things a person can do to help prevent bones from leaching calcium.
For example, a diet too high in animal protein, such as the Atkins diet, can strip calcium from the bones.
“A vegan diet which includes a wide variety of fruits, vegetables, whole grains, nuts, seeds and legumes provides adequate calcium, without the problem of animal proteins which leach calcium from the bones,” Gladden said.
She also recommends these behaviors for a vegan or anyone who wants to prevent bone loss:
• Keep salt intake low. Excessive sodium consumption accelerates calcium excretion through the kidneys.
• Don’t smoke. Smoking can kill the young bone cells, the osteoblasts, which are constantly regenerating.
• Don’t drink too much caffeine.
• Get enough weight-bearing exercise, such as walking, tennis and weight lifting.
• Eat plenty of fruits and vegetables that are full of nutrients including vitamin C to build collagen, the basic network of tissue within the bones.
• Consuming a lot of soft drinks or alcohol can decrease bone turnover.