Osteoporosis and Bone Health
Imagine the internal structure of bone as being like the wood foundation of a house. The process of osteoporosis is similar to what happens during a termite infestation of a home’s foundation, whereby termites slowly eat away at the wood supporting the structure. At some point, so much wood is consumed that the strength of the foundation is compromised and it begins to fail. This is not unlike the progressive nature of osteoporosis; over time, the internal architecture of bone is eroded as a result of a number of factors that eventually increase your risk for fracture (bone collapse). The term osteopenia, or low bone mass, refers to a condition of reduced bone density that has not yet progressed to osteoporosis. Those diagnosed with this condition should still be monitored to ensure that the condition does not get worse.
Osteoporosis is the most common disease affecting the skeleton and is one of the most important public health issues facing Americans. Consider the number of people affected by bone fracture: over 50% of women and 20% of men over the age of 50 will suffer an osteoporotic fracture at some time in their lives. Sadly, one in six women will experience a hip fracture, the most devastating type of osteoporotic fracture. Although an osteoporotic fracture can be devastating, the good news is that because this disease progresses slowly, you can take a number of steps throughout your lifespan to reduce your risk of developing it.
Causes of Osteoporosis
During growth and young adulthood, the skeleton is busy changing in size, shape, and density to ultimately support the physical needs of an adult. In adulthood, the skeleton remains relatively stable but is still constantly undergoing a process called bone remodeling, in which bone repairs and renews itself. During bone remodeling, old bone cells replaced with new bone cells in roughly the same amount. Many processes, however, can “uncouple” bone balance. With normal aging, bone breakdown outpaces buildup causing up to 1% of bone to be lost per year after around age 30. Certain conditions, such as estrogen loss from menopause or an overactive thyroid gland, may increase bone breakdown and slow down bone buildup, causing further overall loss of bone. On the other hand, pharmaceutical agents that stop the breakdown of bone, and physical activity, which causes bone to be built, can each cause a net bone gain.
Because bone is a dynamic tissue throughout life, however, strategies to slow down the breakdown of bone and to build new, stronger bone are useful at any life stage. Keep in mind, though, that many factors influence the state of your bones at any given time. The development of osteoporosis is complex, and no single factor can take the sole blame for the disease. Some of the factors you can control, and others you cannot.
Risk Factors for Osteoporosis
Your risk of osteoporosis is influenced by many factors, some of which you can control or modify, and others that are outside of your control.
Risk Factors You Cannot Control
• Being female
• Having a thin or small frame
• Being of advanced age
• Having a family history of osteoporosis
• Being postmenopausal, including early or surgically induced menopause
• Being male, with low testosterone levels
• Being Caucasian or Asian (although African Americans and Hispanic Americans are at significant risk as well)
Risk Factors You Can Control
• Having a diet low in calcium and vitamin D
• Being inactive
• Smoking, including exposure to secondhand smoke
• Excessive use of alcohol (more than three drinks per day)
Risk Factors You May Be Able to Control
• Abnormal absence of menstrual periods (amenorrhea)
• Anorexia nervosa (eating disorder characterized by low body weight)
• Prolonged use of certain medications, such as corticosteroids and anticonvulsants