A new study found a link between the two, but find out if experts are concerned before you freak out.
Your bones and your brain may seem like fairly separate systems, but they may have more of a connection than you might think.
As it turns out, people with low bone density are more likely to develop the debilitating brain disorder that is dementia later in life, according to a study published in Neurology, the medical journal of the American Academy of Neurology. Now, this doesn’t necessarily mean you should immediately swap your Sudoku for milk-chugging sessions in an attempt to combat dementia with calcium. While doctors are impressed by these findings, they want people to take the results with a grain of salt.
“This is a very important study because they have followed people for over 10 years, which is statistically significant, but it didn’t prove that one can cause the other because the study was observational, meaning there was no medical intervention,” says Nahid Rianon, MD, who is a professor of family medicine with McGovern Medical School at UTHealth Houston.
Should you disregard the findings altogether because of this? Probably not. We spoke to experts about how to apply this information to your own health habits.
Can bone loss lead to dementia?
Over the span of 11 years, researchers in the Netherlands analyzed 3,651 healthy adults around 72 years of age on average. Participants took a physical exam every four to five years to help researchers track bone density and cognition.
Researchers found that participants with lower bone mineral density at the femoral neck — or the bone that links the thigh to the pelvis — were linked to a 42 percent increased dementia risk than those with stronger bones. Unlike previous studies, this calculation accounted for a comprehensive range of factors, including age, gender identity, medication use, education level, and family history of dementia.
“Participants with low femoral neck and total body bone mineral density and low trabecular bone score were more likely to develop dementia,” the study concluded. “Further studies should focus on the predictive ability of bone mineral density for dementia.”
While researchers aren’t sure why exactly there may be a connection, they noted that low bone density and dementia also tend to be more common with older age. The data backs this up: roughly 10 million Americans aged 50 and over have osteoporosis, while more than 7 million Americans aged 65 and older are living with dementia. Even though both conditions can occur among younger people, these cases are considered extremely rare. A University of Arkansas study shows that two percent of 164 college-aged women already have osteoporosis. By comparison, roughly 131,000 insured Americans between the ages of 30 and 64 were diagnosed with early-onset Alzheimer’s disease and dementia, according to insurance company Blue Cross Blue Shield.
“The study showed that having low bone density was linked to having a higher risk of developing dementia, but it’s not to say that low bone density causes dementia, so more studies are needed to better understand the connection between the total bone density and memory loss,” says neurologist Anjali N. Patel, DO, who specializes in memory and cognitive disorders at the Atlantic Neuroscience Institute at Overlook Medical Center.
What’s the link between bone and brain health?
While it’s unclear whether bone loss can cause dementia, in addition to being common aging-related conditions, brain disorders and osteoporosis share common risk factors. For starters, Dr. Patel says recent research shows that chronic inflammation may be a contributing factor to both diseases.
“Research studies have suggested that chronic inflammation can influence bone turnover that may lead to age-related osteoporosis,” she says. “Similarly, studies are suggesting neuroinflammation may drive or spread the misfolded proteins in the brain that cause cognitive impairment or dementia.”
Lack of exercise can also play a key role in the development of dementia, but if modified, it can have an incredibly positive impact on your brain health. In fact, several major studies have found that just 30 minutes of vigorous activity — such as walking and even doing common household chores — can significantly decrease the risk of developing dementia (including those who have a family history of the disease).
The same is true for your bones: While not being active can actually result in bone loss, exercising regularly can reduce the rate of bone loss.
But Meredith Warner, MD, says it also matters what type of exercise you’re doing — for instance, strength training is especially important as you get older. That’s because lifting weights stimulates bones to produce more tissue, making them stronger and less prone to fractures or the development of the disease osteoporosis. “Low bone mineral density is linked to the brain through osteocalcin and other proteins that are released because of load-bearing exercise,” she tells us.
What are some ways to boost your bone density?
Other than lifting weights, there are several ways to improve bone health. A relatively easy place to start might be making sure you’re regularly eating nutrient-rich foods, which are also beneficial for your brain health. While it’s well known that top sources for bone-supporting calcium include dairy products such as milk and cheese, other sources like almonds (and almond butter), tofu, and salmon (preferably canned) also pack a healthy punch. For reference, the average adult needs 1,000 mg of calcium per day, and that amount increases to 1,200 mg per day for women over the age of 50 and men over the age of 71, according to the Centers for Disease Control.
Another important nutrient for bone health is vitamin D. Though our bodies make this essential nutrient when exposed to sunlight, Dr. Warner says a “shocking” number of people across the country are deficient because many of us are increasingly spending more time indoors, potentially making our bones weaker as we age. That’s why doctors recommend considering taking supplements (and that could be as simple as incorporating a multivitamin into your daily routine). Getting this important nutrient has also been shown to be key for your brain. Researchers found that vitamin D deficiencies “may accelerate age-related cognitive decline,” according to the peer-reviewed journal, Proceedings of the National Academy of Sciences of the United States of America.
But how much of “the sunshine vitamin” should you be taking? Well, that depends: the Mayo Clinic recommends getting between 600 to 800 international units (IU), but 1,000 to 2,000 IU per day of vitamin D from a supplement is also considered generally safe for adults. Still, our experts emphasize that everyone’s needs are different and recommend getting an accurate measure of your vitamin D levels through a blood test from your doctor. After all, research shows that taking too much could actually worsen bone health — a 2010 study published in the peer-reviewed journal JAMA showed that very high doses of vitamin D were associated with more falls and fractures in older women, so getting the right amount is key.
“Most people will reach their peak bone mass between the ages of 25 and 30 and by the time we reach age 40, we slowly begin to lose bone mass,” says Dr. Rianon. “So it’s important to maintain good health, nutrition, lifestyle, and physical activity to build it.”