Frailty is a syndrome characterized by a decreased ability to adapt to stressors, increasing the risk of adverse health outcomes (falls, hospitalizations, death, etc.). There can be many causes of frailty, but the effects are weakness, loss of muscle mass, loss of balance, and weight loss. Approximately 10% of people ≥65 years old are frail, increasing to 15.7% in people 80–84 years old, and 26.1% in people ≥85 years old.^[1]

People with frailty experience decreased energy, strength, and balance; weight loss; and trouble performing activities of daily living, such as showering, brushing teeth, and getting dressed. Correspondingly, when people with frailty experience physical or emotional stresses, such as death of a loved one, illness, or injury, their physical capacity can decline rapidly.

There is no consensus on the standard diagnostic criteria of frailty. Two diagnostic criteria, the Fried Phenotype model^[2] and the Frailty Index (FI)^[3], are the most widely used.

Since people with frailty manage multiple health conditions, are vulnerable to adverse health outcomes, and require additional social support, treatment is multimodal and should treat the following components:^[4]

• Medical conditions (e.g., diabetes, cardiovascular disease)
• Mental health
• Cognitive impairment
• Decreased mobility
• Participation in life roles
• Social support systems

On their own, protein^[5], Vitamin D^[6], and DHEA^[7], show no effect on frailty status. One study found that milk fat globule membrane supplementation in combination with exercise improved frailty status.^[8] A meta-analysis of randomized controlled trials found that a combination of protein supplementation and exercise can also mitigate the physical aspects of frailty.^[9]

Malnutrition is the predominant concern among people who are frail. Ensuring that people with frailty have enough calories, protein, fruits, vegetables, and micronutrients in their diet can help reduce the risk of experiencing the adverse health outcomes associated with frailty.^[10]

Exercise is another tool that can improve physical function and prevent adverse health outcomes (i.e., falls) in people with frailty. Current guidelines recommend that people with frailty should undergo a physical activity program consisting of aerobic, balance, and resistance training.^[11] Gentler forms of exercise, such as Tai Chi, may also be helpful for people with frailty.^[12][13] Since there are no recommendations for the optimal frequency, intensity, or duration of an exercise program for frailty, the program should be tailored to the individual's health goals and physical capacity.

There is no one cause for frailty. It is a multifaceted disease that can arise from chronic health conditions (e.g., cardiovascular disease, dementia, sarcopenia, type-2-diabetes), aging, or psychosocial factors.