As you’re probably aware by now, I fancy myself a test subject in my own longevity experiment. I got my degree in science, I spent 6 years in clinical research at the University of Pennsylvania, and 99.9% of everything I read is either science or science-related.
One of the biggest things we need in science is control, a level of control I have no interest in subjecting myself to. I’m living in the real world, I have no interest in micromanaging my health to the level that I’m measuring my food, sticking to a set restrictive menu, staying strict to a set exercise and physical activity schedule…you get the idea.
Another big factor in science is having valid measures. Ideally, you have both objective and subjective measures, especially in something like longevity. Who cares if you’re aging slowly when you feel and perform like garbage? But most importantly, you want measures, not measure; relying on a single measure simply won’t cut it.
A recent study looking at different biomarkers of aging illustrates this point nicely. The study found that some of the more objective measures of cellular aging didn’t jibe with the performance measures such as physical and cognitive ability. This shouldn’t be very surprising, and here’s why.
DNA methylation, strength, and mental performance
Of the objective cell-based measures reviewed in this study, the DNA methylation tests reliably predicted aging from a time perspective. This is great, which is why I’m a fan of that type of testing, but the test wasn’t strongly predictive of physical and mental abilities. Not surprising again because they really shouldn’t have a strong relationship with one another; they’re measuring different things that are indirectly related to one another.
The DNA methylation test is basically assessing how many times your cells have divided, which is useful information. It doesn’t directly assess whether you’ve been exercising, eating a great diet, performing mental work, or managing stress well. These factors are probably pretty strongly related to longevity, just as much as how many times your cells have divided. And they’ll have an impact on the DNA methylation test, but it’s not directly related to the specific biological age you’re predicted to have.
For example, I’m 41 years old, and I’d be flat out surprised if my DNA methytlation testing comes back as any less than 36 years old. I’ve also been exercising consistently for about 30 years, which probably puts my strength, muscle mass, and bone density on par with people in their 20s. These people will test younger than I am on the DNA methylation test, but who’s more likely to survive a fall, a massive heart attack, or a stroke in 20 years if they never take to exercise and I keep plugging along?
And what about cognitive ability? Just because a person is younger on a DNA methylation test doesn’t necessarily mean they’re using that youthful brain; remember, youth is wasted on the young. The saying, “You’ve got to use it or lose it” doesn’t only apply to older people.
Applying the DNA methylation/telomere testing appropriately
I recently took the DNA methylation test because I plan on using that information. I think I’ve identified some pretty valuable factors that can allow me to slow down the clock, so to speak. I’ve been following these procedures for about a year, some for longer than others, and I want to see the fruits of my labor.
This first test will function as a baseline, and I plan on retesting in 6 or so months. If my first test is good, I may do the retest after a few months of hedonistic eating and laying around to see if the results are from winning the genetic lottery or making the changes that I’ve made over the last year.
If my first test is not so good, I have a few things I can change that are probably not doing me any favors. My diet on the weekend is pretty terrible, I drink way too much craft beer on the weekends, I could increase my fiber intake, and I could be a little tighter on syncing my circadian rhythms. I think the circadian stuff will probably have a significant effect on my rate of aging, but there’s still room for improvement.
This is where this type of information is valuable, for tweaking stuff and retesting. I don’t really see the purpose of doing it if you’re not going to perform a second test after some form of change. It’s also important to have performance measures such as reaction time, nighttime heart rate, heart rate variability, and subjective measures such as how you feel normally and/or during your workouts.
I feel good, I’m strong, I sleep great, and I don’t really get sick. Generally speaking, I feel pretty resilient, probably more so than your average 41 year old. All that said, I’m interested in finding out if the way I feel is a good representation of how I’m aging.
This is where tests like DNA methylation or telomere testing can be useful. If my results come back good I probably won’t change my lifestyle since I feel great. If my test comes back bad, I’ll probably do a little tweaking.
If I had good test results but didn’t feel as good as I currently do, I’m not sure I’d put a lot of weight behind the testing. As this biomarker study pointed out, objective cellular measures don’t necessarily equate to good performance measures. To optimize healthspan, and likely lifespan, you need to look at both types of measures for a complete picture of how you’re aging.