Metabolism plays critical role in reducing frailty risk in older adults, study says

New research suggests that maintaining a youthful metabolism into older age can help protect people from frailty. 

In a new study published in the journal Cell Metabolism on Friday, Dalhousie University researchers found a clear link between frailty and metabolic health in older adults. 

“(A)lthough some octogenarians run marathons, others are severely functionally impaired,” notes the article. “This variability in health among people of the same age has led to the concept of ‘‘frailty,’’ which is an age-related state of heightened risk for adverse health outcomes.” 

Titled ‘The intersection of frailty and metabolism,’ the study involved a review of scientific literature focused on frailty and metabolism. Researchers found a clear link between the two. 

“What I learned from this paper is that there’s this intimate link between metabolism and frailty, such that as you become frail, it starts to impair your metabolism,” lead author Dr. Susan Howlett said in an interview. 

“As your metabolism is impaired, it starts to impair functioning. And this then feeds back so that you become frailer, and you get this vicious cycle.”

By interrupting that cycle and modifying metabolism, Howlett said people can be helped “tremendously.”

“And it’s not going to just improve your metabolism. It’s also going to improve your fitness, it’s going to probably reduce your disease burden,” Howlett explained. 

Howlett, who helped develop a frailty index widely used in animal research, is a professor in Dalhousie University’s department of pharmacology. She described metabolism as the body’s ability to take in nutrients, deal with waste, and create energies for tasks related to our cells. Many of those processes become dysregulated as we get older. 

“It’s like when you go to your high school reunion and you look around. And if you’re a certain age, 50 or probably even 40, you’re like, ‘Ooh, people age at different rates,’” she said.

Interventions that reduce frailty

According to the study, the evidence demonstrated that modifying metabolism through  specific interventions can affect the degree of frailty in both human and animal models. For example, combining exercise with taking protein and other amino acid supplements reduced the risk of frailty in older people. This was especially true for women, who tend to be more frail than men. The study’s conclusion noted the following:

Investigations in older people at risk of frailty show that protein and BCAA supplements, especially when combined with exercise, can reduce their degree of frailty. By contrast, preclinical studies have focused on reducing dietary calories and/or protein consumption as strategies to mitigate frailty. These discrepancies highlight the importance of considering the context of interventions designed to affect frailty in vulnerable older individuals. 

It is possible that dietary restrictions may prevent frailty if started in younger populations but exacerbate rather than improve outcomes if started in frail older people. Overall, the exploration of new multidomain interventions designed to maintain a youthful metabolism is a promising area for preclinical mechanistic studies and human intervention trials.

Howlett said as the study came together over the last year, she was inspired by what she learned.

“We know strategies that can preserve a youthful metabolism, right? And that includes staying physically active and strength training,” she said.

“When I reviewed the literature, strength training, especially if given with adequate protein or protein supplement in women especially, really reduces frailty.”

‘If you’re not doing anything, start’

If people take anything away from the journal article, Howlett hopes it’s the knowledge that there are things they can do, starting today, to decrease their chances of either developing frailty, or having their frailty accelerate. And it doesn’t have to be expensive.

“If you’re not doing anything, start. Get out and do a walk. You don’t have to go and run a marathon, you just have to increase your activity. Start thinking about this,” Howlett said. 

“And for women, I would really like to say lift weights and don’t worry about becoming this huge muscle bound person…I’ve been doing this for more than a year myself, and I couldn’t do push-ups, and now I can. I can knock off 30..It came from doing one push up. Then I did two.”

More muscle, she said, is good for your skeleton and for bone density. But it can also help reduce your chances of frailty.

“Your whole body, it’s all connected, right?…We just need to try and keep it working well into later life. That’s going to help us resist diseases of old age and age in a more healthy fashion, because it’s shown that these things can reduce frailty,” Howlett said. 

“It may not be a one size fits all package. If you’ve got an obesity problem that could be slightly different. You might want to try a weight loss program there first. But that could involve walking. Using your body is a really good way to keep it working.”