Considered a “silent” disease, osteoporosis is a condition that usually has no outward signs or symptoms but can have detrimental impacts on bones. One in two women and up to one in four men will break a bone in their lifetime due to osteoporosis, a condition that occurs when the body loses too much bone or does not make enough.
Known to be true for decades is how dairy’s nutritional components (calcium and vitamin D, for instance) can help support bone health. What is lesser known is how other nutritional aspects of dairy foods (particularly its probiotic elements) and high-fiber foods (including fruits and vegetables) impact the gut microbiome, which in turn may help protect bones.
Extensively exploring these associations is Kelsey Mangano, PhD, RDN, nutrition program director and associate professor at the University of Massachusetts Lowell. Mangano has co-authored numerous studies investigating how specific foods known to support a healthy lifestyle may also impact bone health. In a recent conversation with Mangano, she discusses her research, what is new in the world of bone health, dairy’s role, and certain steps individuals can take to prioritize their musculoskeletal system.
Q: What led to your interest in bone health? Did something specific spark your interest?
Mangano: When I was a senior in my undergraduate program, part of the requirements was to do a one-month rotation in a research lab. I worked on a clinical trial assessing whether protein supplementation could augment bone mass in postmenopausal women. I loved working with the study population. Through this experience, I realized how complex bone tissue is and how amenable it is to change through dietary influencers. That was the initial spark.
Some of your published research underscores the eating patterns and lifestyle of the Puerto Rican population and its impact on bone health. What led to researching this population?
A lot of my original work was with the Framingham Heart Study. That cohort was a predominantly white population. UMass Lowell serves a more diverse population. My colleague here is the principal investigator of the Boston Puerto Rican Osteoporosis Study. I was just enamored with their work, which provides visibility and new health knowledge for the second largest Hispanic subgroup in the United States. I joined their research center [the Center for Population Health, which Mangano is now associate director]. My colleagues and I published a paper looking at the prevalence of osteoporosis among Puerto Rican adults. Men had higher rates of osteoporosis compared to any other sub-cohort. It was interesting to see how aging bone and influencers of bone health differ by individual backgrounds. I wanted to learn more about unique risk factors for low bone mass in this population so that we could stop giving blanket recommendations for bone health regardless of a person’s genetic and cultural background. What we’re finding is that people respond to nutrition and lifestyle preventative measures differently. I became excited to help contribute to representing a population of people that was underrepresented in health research.
You also co-authored a study that found increased intake of certain types of fruits and vegetables led to a decreased risk of osteoporosis.
That was an interesting finding. It provided new information because not only did the study show that higher fruit/vegetable intake was related to better bone health, but if you eat a variety of fruit and vegetables day in and day out, those people had even better bone health. It seems that fruit/vegetable intake was linked to positive bone health outcomes, possibly by enhancing metabolites [a substance made or used when the body breaks down food] that are helpful for bone health. Our work also showed that the fruit/vegetable metabolites related to better bone health were different for women than they were for men. This suggests that diet may impact bone through different pathways by sex.
It’s possible that the gut made some of these metabolites because of what people ate. Could the gut itself impact bone health?
The link between the gut microbiome and bone is quite strong. A consensus of research shows that the gut microbiome can help shape how much of the nutrients are absorbed and how it directly affects our immune system. [Mangano has co-authored a literature review underscoring bone health and its relationship to the gut microbiome across race and ethnicity groups.] Our immune system is linked directly to how we build bone. It also seems that gut microbiome shapes inflammation or lack of inflammation, and that also has effects on musculoskeletal tissue.
Your research also has investigated dairy foods. What do we still know to be true about dairy and bone health?
Our research confirms that those individuals with higher dairy intake had the best bone health. That positive relationship is even stronger with individuals with adequate vitamin D levels.
That can be in part because vitamin D supports calcium absorption. Dairy provides one of the most bioavailable forms of calcium, and many dairy foods are fortified with vitamin D, which supports more calcium absorption. There’s additional research that suggests that specific fatty acids from milk and other dairy products can benefit the gut, which can benefit bones. If a person is consuming fermented dairy [yogurt or cheese], some small clinical trials have shown that these foods have a positive influence on bone health. It seems a bit bigger than dairy just providing calcium. Dairy is a much more complex food than we originally appreciated.
So we can think of calcium and vitamin D as a direct mechanism to bone health. You’re giving bones the nutrients they need. Fruit and vegetables are an indirect mechanism that can affect the gut microbiome and human metabolome [a snapshot of our body’s chemical activity], which can positively impact bones.
What dietary recommendations would you give individuals who want to start improving their bone health?
Focus on eating at least five servings of fruits and vegetables daily. Different fruits and vegetables will provide different nutrients that we know can impact the bone healthfully. Focusing on foods high in calcium and vitamin D also remains a priority. The most bioavailable form is dairy. Variety is key. Consuming different dairy foods day to day and week to week could have the most positive effect on bones. For example, some dairy foods have a greater proportion of calcium in every bite, where others are unique in that they provide probiotics, and still others provide unique combinations of healthy fats.
