Last week, I had a conversation with a vibrant, independent 96-year-old, who was excited to share her thoughts about the current election cycle.
It's becoming more common to live into your 90s: according to the National Institutes of Health, those who were more than 90 years old increased by 2.5 times over a 30-year period from 1980 to 2010 in the U.S. (1). Researchers refer to this group as the "oldest-old," which includes those over age 84.
What do these "oldest-old" have in common? According to one study, they tend to have fewer chronic medical conditions or diseases. As a result, they typically have greater physical functioning and mental acuity, which allows them a better quality of life (2).
A study of centenarians found that they tended to be healthy and then die rapidly, without prolonged suffering (3). In other words, they stayed mobile and mentally alert.
While genetics are a factor that can predict your ability to reach this exclusive club, lifestyle choices also play an important role. Let's look at the research.
Does exercise really help extend our lives?
We're repeatedly nudged to exercise. This is not vanity; it can have a direct impact on our longevity and health.
One study of over 55,000 participants from ages 18 to 100 showed that five-to-ten minutes of daily running, regardless of the pace, can significantly impact our life span by decreasing cardiovascular mortality and all-cause mortality (4).
Amazingly, even if participants ran fewer than six miles a week at a pace slower than 10-minute miles, and even if they ran only one to two days a week, there was still a decrease in mortality compared to nonrunners. Those who ran for this very limited amount of time and modest pace potentially added three years to their life span.
An editorial that accompanied this study shared that more than 50 percent of people in the U.S. do not achieve the current recommendation of at least 30 minutes of moderate exercise a day (5).
One study of over a quarter-million people found that walking just 3867 steps a day started to reduce the risk of dying from any cause, and every additional 1000 steps reduced risk of death from all causes another 15 percent (6). The researchers could not find an upper limit to the benefits.
For those 85 and older, all-cause mortality risk was reduced 40 percent by walking just 60 minutes a week at a pace that qualified as physical activity, not even exercise.
What is the best protein source?
Many are questioning the value of a long-standing dietary paradigm that suggests we need to eat sufficient animal protein to support us as we age.
In an observational study of 7,000 participants from ages 50 to 65, researchers found that those who ate a high-protein diet with greater than 20 percent of their calories from protein had a had a 75 percent increase in overall mortality, a four-times increased risk of cancer mortality, and a four-times increased risk of dying from diabetes during the following 18 years (7).
However, this did not hold true if plants were the protein source. Interestingly, they found a high-protein plant diet may actually reduce the risks, not increase them. The reason, according to the authors, is that animal protein may increase insulin growth factor-1 and growth hormones that have detrimental effects on the body.
The Adventists Health Study 2 of over 73,000 participants with a median age of 57 years reinforced these findings (8). It looked at Seventh-day Adventists, a group that emphasizes a plant-based diet, and found that those who ate animal protein once a week or less experienced a significantly reduced risk of dying over the next six years compared to those who were more frequent meat eaters.
What does systemic inflammation tell us about longevity?
The Whitehall II study included 3,044 participants over the age of 35 who did not have a stroke, heart attack or cancer at the beginning of the study (9). Researchers measured a specific marker for inflammation, interleukin-6 (IL-6). They found that higher levels had negative impacts on participants' healthy longevity. If participants had elevated IL-6 (>2.0 ng/L) at both baseline and at the end of the 10-year follow-up period, their probability of healthy aging decreased by almost half. The good news is that inflammation can be improved significantly with lifestyle changes.
The bottom line is that lifestyle choices are important to healthy longevity. A small amount of exercise and consuming more plant protein than animal protein can contribute to a substantial increase in healthy life span. IL-6 may be a useful marker for inflammation, which could help predict healthy or unhealthy outcomes. Your doctor can test to see if you have an elevated IL-6. If you do, lifestyle modifications may be able to reduce these levels.
References:
(1) nia.nih.gov. (2) J Am Geriatr Soc. 2009;57:432-440. (3) Future of Genomic Medicine (FoGM) VII. Presented March 7, 2014. (4) J Am Coll Cardiol. 2014;64:472-481. (5) J Am Coll Cardiol. 2014;64:482-484. (6) Eur J Prev Cardiol. 2023 Dec 21;30(18):2045. (7) Cell Metab. 2014;19:407-417. (8) JAMA Intern Med. 2013;173:1230-1238. (9) CMAJ. 2013;185:E763-E770.