This sobering quote reflects the daily reality for many older Australians, for whom injuries due to falls may lead to immobility for the rest of their lives. “I am finished, completely finished…The most important thing is to stay on my feet.”
One Australian is hospitalised approximately every five minutes due to a fall, which was estimated to have cost the national health service $3.9 billion in 2015-16. About a third of people aged over 65 experience
a fall each year.
In addition to the trauma and injury associated with the fall itself, patients often have prolonged impaired mobility, remaining functionally dependent upon others. Injuries from a fall, including hip fracture, substantially increase mortality risk; consequently, the fear of falling can trigger social isolation and depression, compromising even uninjured people’s quality of life.
Falls have many contributing factors, making prevention complicated. Besides muscle function, which comprises strength and physical function, other well-established falls risk factors include visual impairment, use of multiple medications, chronic disease, and the physical environment (e.g., tripping hazards).
Exercise has emerged as one key factor in lowering falls risk, likely through its ability to improve muscle function and prevent chronic disease. But exercise is only one piece of the puzzle: nutrition is also significant.
From a nutrient perspective, research has typically focused on protein and vitamin D (with calcium) for musculoskeletal health. However, supplements may only be beneficial in the event of deficiency – an important consideration for clinicians.
Nevertheless, maintaining circulating vitamin D levels at 75 nmol/L or above is associated with lower long-term risk for both injurious falls and hip fractures, the latter likely due to higher bone mineral density at the femoral neck and hip.
From a protein perspective, if intake is approximately ≥1.0 to 1.2 grams per kilogram of body weight per day, supplementation (especially in the absence of resistance exercise) is unlikely to increase muscle strength or mass.
Despite the wealth of research around falls prevention, the importance of other aspects of diet remains largely unknown, especially in community settings. Unsurprisingly, national nutrition guidelines specific to preventing falls do not exist.
An emerging research area is the potential for vegetables and their components to improve musculoskeletal health, especially in the prevention of diseases such as sarcopenia (low muscle mass and strength) and osteoporosis.
When considering clinical outcomes, superior muscle function observed with higher consumption of vegetables (over three serves/day) possibly explains lower long-term injurious fall and hip-fracture risk. Notably, consuming at least one serve a day of cruciferous vegetables (e.g., broccoli, cauliflower, cabbage, Brussel sprouts) is shown to provide the greatest benefits.
Cruciferous vegetables represent a rich source of organosulphur compounds known for their anti-inflammatory properties, as well as vitamin K which has also been linked to better muscle function and bone strength.
For example, a diet consisting of 200g per day of vegetables, providing ~165 ug/d of vitamin K, for four weeks reduced bone turnover markers (e.g., total and undercarboxylated osteocalcin). This suggests improved osteoblast function, which would promote bone integrity if continued over time. Inversely, vitamin K insufficiency can increase injurious falls risk.
Nitrate is another nutrient found in high concentrations in green leafy vegetables and beetroot. Health benefits of vegetable-derived nitrate have typically centred around improved vascular function and reduced risk for cardiovascular events. However, recently, diets rich in vegetable-derived nitrate (~100 mg/d) have been linked to better muscle strength of the upper and lower-limbs, as well as physical function (e.g., timed-up-and-go test) in older adults.
The aforementioned benefits to muscle function were observed irrespective of the amount of physical activity performed (e.g. sedentary/active). Randomised controlled trials supplementing high-nitrate beetroot juice report similar improvements to lower-limb muscle power. Such findings are promising as improving muscle function substantially reduces fall and fracture risk.
In summary, lifestyle intervention comprising diet and exercise are essential for fall and fracture prevention. Whilst the importance of resistance and balance exercise is well regarded, until recently the significance of diet remained less clear.
Specifically, vegetables providing a range of nutrients including vitamin K and nitrate may be key in supporting muscle and bone health. Therefore, key messages from public health campaigns around increasing fruit and vegetable intake such as ‘Go for 2 & 5’ must continue to be well promoted.
Key messages
- Resistance exercise and a healthy diet are essential for fall and fracture prevention
- A daily serve of green leafy and cruciferous vegetables provides sufficient vitamin K and nitrate to promote musculoskeletal health
- Consumption of five serves of vegetables daily, including a diverse range, should be promoted.
– References available on request
Author competing interests – nil