Studies Indicate Boron in the Diet May Help Prevent Osteoporosis
Boron, a trace element not previously known to be important in the human diet, may play a key role in preventing osteoporosis, a debilitating bone condition that afflicts many older women, U.S. scientists reported in a paper to be published today.
If confirmed by additional human studies, the finding may have broad implications because osteoporosis, or the loss of calcium from the bone, affects up to 20 million mostly post-menopausal women in the United States alone.
Such calcium loss weakens the bones, leaving them less dense and more fragile--and more vulnerable to fractures.
Osteoporosis is believed to be caused by reduced production of estrogen, a female hormone. The disease is treated effectively by administering a synthetic form of the hormone. But some women reject estrogen because of its side effects, including nausea, vomiting, swelling and headaches, and because of concern about the long-term safety of estrogen therapy.
In the experiments, the amount of boron necessary to minimize calcium loss was equivalent to the amount that would be obtained in a diet containing normal amounts of fruits and vegetables, according to nutritionist Forrest H. Nielsen of the Department of Agriculture’s Human Nutrition Research Center in Grand Forks, N.D.
Boron is found in relatively high levels in apples, pears, grapes, nuts and leafy vegetables. “What we really want to say is that a healthy diet can minimize bone loss, and that supplements aren’t necessary,” Nielsen said.
Researchers had not previously suspected boron’s beneficial role in human diets because it is so subtle, he said. Hence, there is no recommended daily requirement for boron and no boron supplements are sold.
But whether boron supplements could aid women who already have severe osteoporosis is not known.
Nielsen’s findings appear in the November issue of the Journal of the Federation of American Societies for Experimental Biology.
A leading biologist, Paul Saltman of UC San Diego, said that Nielsen has previously done “brilliant work” on the role of trace elements in animals and humans. “He has a long track record, you have to trust this man,” Saltman said.
Nielsen stumbled upon boron’s importance while trying to determine what elements must be present in the diet of chickens for them to grow properly. This is determined by feeding the birds a synthetic food whose composition is precisely known.
At the North Dakota center, researchers observed that one of two flocks was growing poorly and had abnormalities in their legs caused by bone softening. This flock, it turned out, had received a different synthetic food than the healthy flock.
When the researchers compared the diets, they found that the sickly birds were not receiving boron. After boron was added to chicken’s food, their bones reached their normal hardness.
Control of Diet
At the time, Nielsen and his colleagues had been planning to study the effects of aluminum and magnesium in a group of 12 women, aged 45 to 82, who volunteered to live at the center under close supervision for six months. Aluminum and magnesium, which are also found in fruits and vegetables, are thought to assist bone formation.
The women were to be fed a diet of beef, pork, rice and milk, but few fruits and vegetables, for 119 days. Then they were to be given supplements of aluminum or magnesium, along with the same diet.
“Because the diet was low in boron, I convinced my colleagues that we should also try giving them boron supplements,” Nielsen said.
The aluminum and magnesium supplements did not significantly decrease calcium loss.
But within eight days of receiving specially made boron capsules, the women’s calcium loss, which resulted from the deficient diet, was reduced by nearly 50%.
“The results were so dramatic they just jumped out at us,” Nielsen said.
Doubled the Level
The study also showed that the boron nearly doubled the women’s blood levels of the female hormone estrogen, which regulates the body’s use of calcium.
“The reason we are so excited about this is that there is only one known effective therapy for preventing calcium loss, estrogen replacement therapy, and we have been able to increase estrogen naturally,” Nielsen said in a telephone interview.
Nielsen noted that the results should not have been completely unexpected. “Seventh Day Adventists are vegetarians and they have a much lower occurrence of osteoporosis than other Americans,” he said, “while Eskimos eat almost no fruits and vegetables and have a high incidence (of osteoporosis).”
