By Savannah Robbins, RDN, LDN
Dietitian, St. Luke's Hospital
SavannahRobbins@iammorrison.com As the older adult population grows exponentially, the concern of hip fractures increases. In the year 2000, 1.6 million hip fracture cases occurred, and by the year 2050, this number expects to triple. The increase in hip fractures poses a threat to our older adults suffering from the fracture and our hospitals and rehabilitation centers as the population rises. Hip fractures in older adults can lead to early decline through decreasing mobility and increased mortality risk.
Data shows a correlation between a person's body mass index (BMI) and their risk of hip fractures. BMI is calculated by the person's height and weight (kg/m2). A BMI less than 18.5 is underweight, a BMI between 18.6 to 24.9 is normal, a BMI between 25 to 29.9 is overweight, and a BMI greater than or equal to 30 is obese. Research shows that women with BMIs of 25 to 27.4 kg/m2 and men with BMIs of 27.5 to 29.9 kg/m2 are at the lowest risk for hip fractures2. The higher the older adults' BMI, the higher their bone mineral density (BMD) is. The positive association with higher BMI and BMD plateaus at a BMI of 30 kg/m2.
Protective mechanisms of an overweight BMI in older adults are attributed to mechanical loading of the bone, higher serum estrogen levels, and adipokines leading to increased BMD and bone mineral content. Older adults with overweight to obese BMIs have the greatest 1-year survival rate, while those with BMIs of less than 22 have the lowest 1-year survival rate.
As we age, our appetite decreases. Ghrelin, a hormone that sends signals through our body to warn of hunger, decreases as age increases. Thus, lowering appetite and, in return, causes weight loss and lower BMI.
So, how do we decrease the risk of hip fractures? It's never easy to eat when you feel full or when foods do not sound appealing. Conscious efforts must be made to maintain weight and adequate energy intake. Try consuming multiple small meals each day, possibly 5-6 meals. Choose nutrient-dense foods to optimize overall calorie intake. Attempt to eat meals with family or friends. Social support at mealtimes can make meals more enjoyable while spending time with loved ones.