I wouldn’t be surprised to see the phrase reverse aging in an advertisement or maybe a tabloid type publication. But last week I started to catch headlines in seemingly respectable publications promising a way to “reverse aging”. That’s quite a promise – one that will likely get your blog post or story a lot of clicks. The first one I noticed was in an online feature associated with Discover Magazine. The feature is called D-briefs and the headline was this:
Healthy Diet and Exercise Reverse Aging in Our Cells.
The headline also used the term “healthy diet” as if this phrase actually means something. We’re told that this “healthy diet” and exercise will reverse aging, in our cells, but since we’re made of cells, it doesn’t feel like much of a qualification. If it reverses ageing in your cells, how could it fail to reverse aging in you? It sounds more systematic and thorough than, say, botox shots.
Turns out this post is little more than a summary of a story with a very similar headline in LiveScience:
Lifestyle Changes May Reverse Aging in Cells
That story starts out with this teaser:
Lifestyle changes may turn back the biological clock, and reverse aging on a cellular level, new evidence shows.
There’s a corny image of a women who looks like her worry lines are being magically peeled off her face – something that might make more sense as part of a botox ad.
The Livescience author, Bahar Gholipour, describes a study by Dean Ornish, whose name is familiar because he wrote at least one popular diet book back in the 1990s that advocated a diet that was not only vegan but extremely low fat. This new study was a small one that included a whole bunch of variables including exercise, yoga, a support group and Dr. Ornish’s idea of a healthy diet.
The researchers took white blood cells from their subjects and measured sub-cellular parts called telomeres – structures at the ends of chromosomes that writers inevitably compare to the caps on the ends of shoelaces. Telomeres reportedly get shorter as we age until they leave our chromosomes naked and exposed and our cells stop dividing and poop out on us. In the study, the telomeres allegedly grew longer in the cells of those who did the super low fat vegan/support group/yoga thing. They shrank in the controls.
Many of us have written about telomeres, since they came up on stories about the life and death of Dolly the cloned sheep, and then work on telomeres and aging led to a 2009 Nobel Prize. One of those prize winners, Elizabeth Blackburn, is apparently also an author of this study, though Ornish seems to have all the quotes.
There are a couple of reasons why I’m not rushing to throw away my Greek yogurt, cheese, or eggs, give up sushi or take up yoga.
First, while telomeres are connected to aging, there’s no direct evidence that the group undergoing these lifestyle changes will age more slowly or live longer, let alone that they underwent some kind of Benjamin Button effect.
Secondly, it was a tiny study. There were 35 participants followed over five years. Only 10 did the lifestyle changes and the other 25 went on with life as usual and served as controls. All 35, we’re told, are men with prostate cancer – which is described as “non-threatening”.
A lot of assumptions seemed to go into the reporting. The LiveScience piece describes the yoga and Ornish diet as “positive” lifestyle changes. But are they? Is there evidence outside the study that either of these things do something “positive” for people? I actually had one of the old Ornish books and the recipes didn’t even let you use olive oil to sauté vegetables. It was somewhat extreme.
And finally, there’s a problem with multiple variables. Here’s a thought experiment. Imagine that the group that did the lifestyle changes was also asked to sing a chant every day and throw a penny in a wishing well? Would you tell readers that chanting and throwing pennies in wishing wells reversed aging in your cells?
Likewise, how to we know the yoga mattered? The study combined a lot of variables, thus making it impossible to sort out which ones, if any, are connected to the observed telomere-lengthening effect. The results seem interesting enough to prompt further studies, but not conclusive enough to warrant making health recommendations. You might think it’s okay because the diet is “healthy” anyway. But do you really know anything about vegan diets and their influence on health? Is there enough evidence behind it?
Adding a skeptical sound bite quote is not enough to capture the nature of the important caveats here.
While most of the stories lacked critical questions, there were a few reasoned, critical takes, such as this one by Larry Husten from Forbes.com, which also importantly noted Dean Ornish is a diet doctor who may have something to gain from any study that seems to favor his low-fat regimen.
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