Understanding Bone Density: Daily Habits and Concerns

Introduction

Searching for the fountain of youth?  Hoping to ‘age gracefully’? When we think about how to best support our bodies throughout our lives, it’s important to consider all parts of the body. One of the most common parts of the body affected by the aging process is our skeletal system, and these effects are more severe in women. More than 200 million people worldwide are affected by osteoarthritis, osteoporosis, osteopenia, and other degenerative disorders, which affect both physical ability and quality of life. Certain lifestyle factors are critical for bone health and density preservation, and often can lead to the degradation process.

Like we have explained when discussing strategies for optimizing health previously, stress management, sleep hygiene, eating strategy, exercise prescription, and self care are determining factors in maintaining and enhancing bone health. There’s one thing to take away – your health is more in your control than you think!

Bone density is generally measured using a T-score, where bone density is compared to young adult density and qualified by either a positive (increased BMD) or negative score (reduced BMD) (Rondanelli et al, 2021). Bone density commonly decreases with age.  With lower bone density there is increased fall risk, bone fracture and break risk, and decreased force absorption throughout the body.

Genetics

Genetics should also be taken into consideration.  When genetics are involved, this process can start earlier in life and present a more critical risk. Family studies show heritability of compromised bone mineral density as high as 82%, indicating a need to make the establishment of preventative measures as early as possible a priority. This data was extrapolated from a twin and family study that showed several single nucleotide polymorphisms that align with osteopenia and osteoporosis development. These are pieces of DNA where a single piece of the DNA has been replaced by a different nucleotide, causing a change in how the DNA is read and used (Cerani, et al 2019; Kim et al, 2018).

Oftentimes, these tests can be rather expensive for genetic testing, and family history can be useful information in determining risk of inheriting these traits. But, regardless of genetics, there are ways to combat bone loss and reinforce bone healing and remodeling.

Eating Strategy

Eating strategy is extremely impactful on bone density. Vegetarians often have decreased bone density compared to those who eat animal products. Other factors such as stress, exercise type and load, hormone status (including thyroid, sex hormones, and pituitary hormones), along with previous activity, are all significant factors in bone density throughout the lifetime and progression of bone changes. In very rare cases, some diseases and illnesses can lead to brittle bones and decreased density.

Malnutrition is one of the most common causes of bone loss and is seen in children and teenagers who aren’t feeding properly for their growth or activity levels (Rondanelli et al, 2021).  Other extenuating circumstances to consider when it comes to bone density include certain medications, immobilization over a long period of time, blood and bone marrow disorders, and endocrine disorders (Rondanelli et al, 2021).

Hormones

Because women tend to develop earlier and experience hormonal changes relatively early in their teen years, they generally reach their peak bone density earlier in life compared to their male counterparts (19.3 for women vs 21.8 for men)(Xue et al, 2020). Certain factors like eating disorders, eating strategy, activity level, and birth control use can affect the peak bone density in women and reduce their peak bone density overall. Men generally reach their peak bone density in their early twenties with testosterone being largely impactful in this bone-building and maintenance process.

The most notable bone density changes generally occur around menopause in women and andropause (manopause) in men, starting in their late forties through fifties and potentially lasting even into their sixties. As you can see in the diagram below, the hormonal drop-off in women is much larger than in men. Women need a sufficient level of estrogen for proper bone density regulation, and if any hormonal changes occur too quickly, can severely affect bone density. With the decrease in androgen hormones through menopause and andropause, bone matrix is not maintained as well and the body does not prioritize density maintenance because of the reduced hormones. While these changes are natural, there are many ways to offset this process and reinforce bones for a healthy, strong life.

Three Focus Points for Bone Health

1. Eating Strategy and Nutritional Supplementation

• Calcium-rich and mineral-rich foods
  • Spinach, broccoli, nuts, cheeses, yogurt, milk, and anchovies are all great sources of dietary calcium, and in countries who regularly consume high amounts of these foods (like Northern Europe) show the highest bone density without requiring calcium supplementation. For the rest of the world, 1,000 mg of calcium is recommended daily. Through many different research studies, it was found that 1,000-1,200 mg/calcium per day was adequate in maintaining bone density and increasing calcification of bone matrix. Most elderly people take 400 mg per day, putting them well below the necessary requirements and increasing fracture risk (Rondanelli et al, 2021).‍
  • Other minerals to be mindful of include phosphorus, manganese, selenium, copper, iron, magnesium, silica, and zinc. This can often be achieved by a broad spectrum electrolyte supplement (Rondanelli et al, 2021).

• Protein Intake
  • Protein intake, especially in menopausal and postmenopausal women and men older than 65, will determine bone density and fracture risk. Those eating at least 0.8 g/kg bw/day and upwards of 2.1 g/kg bw/day had a lower fracture risk and increased bone density in the hips and legs (as measured by Double Photon Beam Absorptiometry (DPA)) (Rondanelli et al, 2021).

• Vitamin DI
  • Sun exposure and supplementation with vitamin D has long been known to aid in bone density preservation. Vitamin D is required for calcium absorption in the digestive tract, and helps with calcium sequestration in the bone matrix. As humans age, the ability to synthesize vitamin D decreases. Clinicians have seen trends between low vitamin D status and diagnosis of osteoporosis and osteopenia due to decreased calcium absorption. Not only is low vitamin D a risk factor for bone demineralization, but low vitamin D also causes muscle weakness, compounding the risk of fractures in older individuals (Rondanelli et al, 2021). Because of the limited dietary sources of vitamin D, most people generally get their vitamin D from the sun or supplementation. In one meta-analysis, researchers found that 800IU/day of vitamin D minimum combined with 1,000 mg of calcium was able to reduce hip fractures and total fractures by 30% and 15%, respectively. Vitamin D supplementation works best for bone density when combined with vitamin K2, calcium, and a healthy fat source (Rondanelli et al, 2021).

• Healthy fats
  • Olive oil, omega fatty acids, and fish oils all play a role in maintaining bone and increasing density over time. One study studied a group of 40 women (mean age of 80) over 16 weeks who were taking some form of omega-3 fatty acid (4 different groups assigned). They found a mixture of fish oil and evening primrose oil increased the amount of collagen in bone matrix and bone matrix density through osteoblast activity (which also requires vitamin K to complete this process) (Rondanelli et al, 2021). Additionally, the balance of healthy fats within our eating strategy contributes to bone health and reduces inflammation overall when we minimize unhealthy fats like omega-6 fatty acids (Rondanelli et al, 2021).

2. Weight-Bearing Exercise

• Resistance Exercise
  • Exercise is the most effective non-pharmaceutical treatment for bone density and fracture risk in older adults (Kemmler et al, 2020). Regular exercise frequency of at least twice a week (and under supervision of a professional who can monitor progress) can make a substantial difference in T-scores and bone mineral density, as demonstrated by DXA scans (Watson et al, 2018). Researchers even found that increasing exercise frequency and intensity in young adults can give that same individual an extra 10 years of strong bones later in life (Watson et al 2018).

• Weight-bearing exercises for controlled stress on bones
  • Particularly, there is an emphasis put on certain types of movements and weight-bearing exercises that load the axial skeleton, or the central part of the skeleton (spine, shoulders, neck, hips and pelvis) (Watson et al, 2018). These weights should be relatively challenging to the person, as increased load is associated with adequate strain on the bone that leads to bone remodeling and restructuring (Kemmler et al, 2020). This means that bone density training should include weightlifting movements close to a person’s one-rep max weight, meaning a weight they could not do really more than 2-3 times. This higher intensity (as determined by load) is even safe for those with very low bone density, as long as the program progresses at a reasonable pace and special attention is paid to form (Watson et al, 2018).

• Impact Loading and Training is Especially Important
  • – Impact training, or training where load is increased across surface joints and long bones, is vital for increasing and preserving bone density. This can be as small as heel drops in a seated or standing position, all the way to a full box jump or box drop. The additional force from gravity and a sudden impact against the direction of gravity translates the force through the bone and reinforces its structure. With repeated exposure to impact loading and training, clients can progressively overload this movement as their bones increase in density (Watson et al, 2018). Consistency is key!

3. Lifestyle Choices

• Alcohol, smoking, lack of activity/weight training/impact training
  • Research has also shown that lack of physical activity and weight training, especially starting young, can limit peak bone density and increase fracture risk later in life. Other factors such as alcohol use and tobacco use can significantly affect bone density through increased inflammation alone. By reducing alcohol consumption and tobacco use, and increasing resistance training and impact training, bone density can shift dramatically following these changes.

• Supplementation based on individual needs
  • For those who are not getting adequate amounts of these nutrients in their daily eating practices (eg. following a particular diet or allergies), it is imperative to supplement accordingly. Those following a vegetarian or vegan diet will have to be careful to include protein supplements, calcium supplements, and healthy fats. If you’re allergic to dairy, find creative ways to work calcium into your eating strategy through dark leafy greens and nuts.

Conclusion

Regardless of age, previous injuries, or genetics, there are always options for improving our health and wellness, and especially caring for our bones throughout our life. Starting young, we can reinforce our bone health through activity and practice good habits.

Adequate nutrient intake provides the nutrients for bone building and maintenance, and a structured training program focused on resistance and impact training creates more structural integrity over time. This sets ourselves up for success later in life, allowing us to be more active with friends and family, more mobile in our everyday life, stronger for all of life’s adventures, and healthier through the aging process.

Sources

Kemmler, W., Shojaa, M., Kohl, M., Schoene, D., & Von Stengel, S. (2020). Dynamic Resistance Exercise and Bone Mineral Density at the Lumbar Spine in Postmenopausal Women: A systematic review and meta-analysis with special emphasis to exercise parameters. Osteologie, 29(3), 194–206. https://doi.org/10.1055/a-1177-4031

Rondanelli, M., Faliva, M. A., Barrile, G. C., Cavioni, A., Mansueto, F., Mazzola, G., Oberto, L., Patelli, Z., Pirola, M., Tartara, A., Riva, A., Petrangolini, G., & Peroni, G. (2022). Nutrition, physical activity, and dietary supplementation to prevent bone mineral density loss: A food pyramid. Nutrients, 14(1). https://doi.org/10.3390/nu14010074

Watson, S. L., Weeks, B. K., Weis, L. J., Harding, A. T., Horan, S. A., & Beck, B. R. (2018). High-Intensity Resistance and Impact Training Improves Bone Mineral Density and Physical Function in Postmenopausal Women With Osteopenia and Osteoporosis: The LIFTMOR Randomized Controlled Trial. Journal of Bone and Mineral Research, 33(2), 211–220. https://doi.org/10.1002/jbmr.3284

Xue S, Kemal O, Lu M, Lix LM, Leslie WD, Yang S. Age at attainment of peak bone mineral density and its associated factors: The National Health and Nutrition Examination Survey 2005-2014. Bone. 2020 Feb;131:115163. doi: 10.1016/j.bone.2019.115163. Epub 2019 Nov 21. PMID: 31760214.

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