insights

                                                                                                                                                                                                                   Read time: 6 minutes

Beyond the obvious functions of protecting vital organs, providing structure and shape, and permitting movement of the body, bones also play a vital role in physiological homeostasis through their nutrient storage and blood cell production capabilities. In addition, the skeletal system is intricately connected to the health of other body systems such as the immune,¹ endocrine,^2,3 and digestive systems.⁴

Bone health is crucial for overall health, and several modifiable and nonmodifiable factors, from aging to genetics⁵ to nutrient insufficiencies, may disrupt the balance of the bone remodeling cycle and negatively impact optimal bone functioning. Research studies also suggest that chronic exposure to environmental toxicants damages bone health and function while also increasing risk of fracture and osteoporosis. What lifestyle-based approaches may help protect bone from the detrimental effects of daily pollutant and chemical exposures?

Heavy Metals, EDCs, and Combined Chemical Exposures

Medical experts and observational study results suggest that exposures to heavy metals such as lead and cadmium, as well as to endocrine-disrupting chemicals (EDCs) such as phthalates and bisphenols, disrupt bone metabolism and may increase risks of osteoporosis, osteopenia, or fracture among some populations.^6-9

A 2023 study that used data from the National Health and Nutrition Examination Surveys (NHANES) 2013-2014 and 2017-2018 found that among 1,777 middle-aged and elderly participants (average age of 59 years; 62% white; 50% male), increased blood levels of cadmium were significantly associated with an increased osteoporosis prevalence.¹⁰ In subgroup analysis, researchers noted that the significant association was only seen in women. Of interesting note, results indicated that selenium may play a protective role, as osteoporosis prevalence decreased as blood levels of selenium increased.¹⁰ A 2022 meta-analysis of ten cross-sectional studies found that among postmenopausal women, even low levels of cadmium exposure may be a risk factor for osteoporosis.¹¹ Further, a recent 2023 observational study investigated the health inequities associated with cadmium exposure and bone mineral density (BMD) among US adults and found that negative associations between cadmium exposures and lumbar BMD were most pronounced among Black women.¹²

Regarding recent EDC studies, a 2020 observational study used data from NHANES from 2005 to 2010 (n=2,267 men and 2,178 women, of which 1,033 were postmenopausal) to measure associations between phenolic biomarkers and BMD.⁹ Among the results, researchers reported that higher urinary levels of bisphenol A (BPA) were associated with a higher prevalence of both osteopenia and osteoporosis in the lumbar spine among women who were postmenopausal.⁹ Most recently, a 2023 in vitro study using human osteoblasts found that after treatment with some BPA analogs, cell proliferation was inhibited in a dose-dependent manner, apoptosis increased at high doses, and reductions in calcium nodule formation on osteoblasts were observed.¹³

In the modern world, daily exposure to a variety of ubiquitous chemicals is difficult to avoid entirely. Research studies have recently investigated the impact of cumulative exposure to multiple hazardous chemicals in relation to bone health. A 2023 study that used data from NHANES 2005 to 2010, 2013, and 2014 (n=6,766 adults; average age 52.9 years) explored the association between urinary levels of phenols, pesticides, phthalates, and polycyclic aromatic hydrocarbon metabolites with BMD measurements and osteoporosis risk.¹⁴ Overall analysis indicated that as chemical exposure levels increased, a significantly reduced BMD was reported for both men and women, while a significantly elevated osteoporosis risk was reported among women only.¹⁴

Air Pollution & Osteoporosis Genetic Predisposition

Ambient air pollutants such as particulate matter (PM), nitrogen dioxide (NO₂), and nitrogen oxide (NO_x) continue to be associated with reduced BMD and increases in osteoporosis and fracture risk.^15,16 Some studies have also explored how genetic predisposition for fracture or osteoporosis may modify the associations between air pollution exposure and bone health.¹⁷ A 2023 observational study analyzed data from the UK Biobank to evaluate the relationship between osteoporosis risk, air pollutants, and genetics.¹⁸ Overall, statistically significant results indicated that as exposures to PM_2.5, NO₂, NO_x, and cumulative air pollutants increased, risk of osteoporosis and fracture also increased.¹⁸ Specifically, researchers reported that compared to the lowest air pollution scores, participants with the highest air pollution scores had a 14% increased risk for osteoporosis and an 8% increased risk for fracture.¹⁸ When considering the osteoporosis genetic predisposition, researchers found the interesting result that participants with high air pollutant exposures and low genetic risk scores had the highest risk of developing osteoporosis—an 86.1% greater risk than participants with low air pollutant exposure and a high genetic risk score.¹⁸ Of note, while family history of hip fracture or osteoporosis may increase an individual’s own osteoporosis or fracture risk,^19,20 studies continue to clarify how much the risk increases among different populations and the polygenic factors involved.⁵

Another interesting 2022 study (n=529 women; median age 76 years; Beijing residents) investigated the relationship between traffic-related air pollution exposure and the incidence of osteoporotic fractures.²¹ In the study, distances were designated in units representing the closest, medium, and farthest proximities. After adjusting for confounders, analysis indicated that compared to the farthest distance, those living closest to a major roadway had a 159% higher risk of osteoporotic fracture incidence while those living within a medium distance had an 87% higher risk.²¹

Clinical Applications: Reducing Exposures & Lifestyle-Based Approaches

Avoiding or reducing pollutant and hazardous chemical exposures is an important component for bone health as well as for overall health and wellness. Awareness of potential chronic exposures and the level of exposure are important factors to discuss with patients as they may indicate the extent of impact and inform any treatment considerations.

As part of a patient’s personalized bone health and treatment plan, specific strategies to reduce chronic toxicant exposures may include avoiding direct and indirect exposure to cigarette smoke, avoiding plastic food and beverage packaging, using HEPA air purifiers, removing outdoor shoes upon entry to the home, and choosing organic versions of high-pesticide produce. As part of IFM’s extensive toolkit, available to IFM members, Reducing Exposures to Harmful Chemicals is a clinical tool that provides a range of valuable suggestions and approaches for clinicians and their patients.

In addition to reducing exposures to environmental toxicants, other lifestyle-based approaches may be implemented to support skeletal health. Research studies suggest that anti-inflammatory, Mediterranean-style diets,^22,23 physical activity and resistance-based exercise,²⁴ and specific vitamins and minerals, supplements, and nutraceuticals such as calcium, vitamin D, vitamin K,²⁵ isoflavones (abundant in soybeans and other legumes),^26,27 omega-3 fatty acids,²⁸ and probiotics^26,29 may positively impact bone density and quality.

Functional medicine practitioners approach each patient with toxicity concerns through an individual assessment. The Toxin Exposure Questionnaire is another resource within the IFM Toolkit that is used to track a patient’s vulnerability to harmful chemicals and the progress of therapeutic interventions. Based upon a personalized treatment intervention, optimizing a patient’s nutritional status, ensuring adequate fiber and water intake, eating more phytonutrient-dense and diverse foods, and supporting liver function through targeted, nutrient-dense diets such as IFM’s Detox Therapeutic Food Plan may be among the treatment approaches to help improve the elimination of toxic compounds and to alleviate toxic burden.

Understanding how environmental toxicants impact body tissues and taking practical steps to improve biotransformation and detoxification pathways may help to improve a patient’s overall health and well-being. Learn more about those clinical tools and personalized approaches that help ensure health at IFM’s Environmental Health Advanced Practice Module (APM).

Related Articles:

The Bone and Mitochondria Connection

Hormones and Bone Health

Connecting Bone and Gut Health

Neighborhood Health: Pollutant Exposures & Chronic Disease Risk

Toxin Exposure Questionnaire Tracks Vulnerability to Harmful Chemicals

References

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