National Post (National Edition)
How to turn on the genes that can make you live longer.
THERE’S GENES FOR IT AND WAYS TO TURN THEM ON
Until recently, our knowledge about aging well appeared straightforward: low-fat foods — with a good portion of carbohydrates and smaller helpings of proteins and fats — would help us stay healthy. We could further help ourselves by making sure we were getting enough antioxidants, from fruits, vegetables and supplements.
It seemed to work: the average age in wealthy nations has climbed gently for decades, with people now likely to reach their late seventies or early eighties, and each generation living longer than the last. Clearly, we have been doing something right.
Until now.
In 2015, for the first time since the early Nineties, life expectancy in the United States declined. It has continued to drop, with more people dying from diseases such as Alzheimer’s and diabetes, according to the Centers for Disease Control and Prevention. And it’s not just the U.S. — something similar is happening in other rich countries. Granted, flu and pneumonia remain major culprits, but so too are the ailments of aging: cancer, Alzheimer’s and cardiovascular issues. The obesity epidemic is at least partly responsible.
It wasn’t meant to be like this. For decades, many people followed the so-called “heart-healthy” diet, cutting out saturated fats and eating cereals and whole grains.
But last year, the groundbreaking Prospective Urban and Rural Epidemiological (PURE) study — designed to examine the effects of lifestyle behaviours on the health of 135,000 people in 18 countries, over a decade — turned everything upside down. Researchers found that those who ate butter and eggs had fewer strokes and lived longer, while those who ate their cornflakes died younger.
When I started practising medicine, 25 years ago, I truly believed that butter was bad and margarine was good. But, over the course of my career, I’ve learned that, every five years, we need to unlearn half of what we thought was true. Medicine evolves at a breathtaking pace.
I have also learned that patients generally get much more benefit from making the lifestyle changes that prevent disease, rather than taking a tablet to treat it. To stay relevant, I realized, I needed to know more than just how to tackle illness. The book Younger for Longer is a culmination of that 25-year journey and shares the secrets I have learned about how to maximize your health.
As with so much, it’s out with the old and in with the new. Two important “facts” about aging — what we thought caused it, and how we can slow it down — have been proven wrong. And, if we heed both these things, we can switch on our longevity genes and potentially live longer.
Firstly, it is sugar and refined carbohydrates, not saturated fat, that are public enemy number one — strongly linked to obesity.
Secondly, antioxidants are not the health-hit we once hoped. Many of us have spent years consuming them, in the form of vitamin C pills or vitamin E. But it now seems this can harm us more than it helps. In the Sixties, Dr. Denham Harman explained that our cells are damaged by free radicals, and that antioxidants attack those free radicals and, in so doing, protect us.
He was right, but there was a problem, because it turns out that our cells have their own powerful antioxidant system called SOD (superoxide dismutase). Taking lots of antioxidants seems to make our own SOD system lazy, which means it doesn’t do its job as well. It turns out that a better solution is to exercise every day, because that wakes up our powerful SOD system, which is a far stronger antioxidant than any supplement we could swallow.
We now know that exercise reduces stress, stimulates brain growth, cuts our risk of diabetes and heart attack, and maintains healthy muscles and nerves — all of which are essential for longevity. In fact, you could argue that exercise (short and intense is the latest advice) is the single most beneficial thing we could do to stay younger for longer.
Unfortunately, though, none of this new knowledge will stave off death ... or might it? For millennia, we have known our allotted time is about threescore years and ten. But many other animals we share this planet with, do things differently.
The Turritopsis dohrnii jellyfish, for instance, just five millimetres tall, never dies unless eaten. Its other name is the “immortal jellyfish”. The bowhead whale — one of the largest mammals on Earth — can live to 200. Its sheer size ought to make it more prone to cancer, but it manages to dodge the disease thanks to specific genes that control its cell-division cycle and guard against it.
You might ask what relevance this has to us. The point is that we assume we will only live 70-odd years, but if we look at nature there are mechanisms that allow animals to survive far longer. Scientists hope this knowledge can one day be transferred to helping humans.
Academics have also started to look at the growing numbers of people who live to 100. They have found that many centenarians have special longevity genes, called geronto-genes.
These are not common. Scientists hope, in the future, to be able to transfer healthy geronto-genes from the lucky few to the rest of us — although to do so raises serious ethical questions about the genetic modification of humans and there’s no knowing what other effects meddling with our DNA could have on our health. So how can you and I can go about acquiring some longevity genes right now?
In fact, many of us will already have them. The human body contains about 20,000 genes, most of which — unless needed — lie dormant. Switching on whatever longevity genes we already have, is merely a case of living healthily. If we exercise today, and cut out sugar and starch, then we will activate them. If we lie on the sofa all day tomorrow, and eat pizza and chips, then we will likely turn them off. So if we want to consistently fire up our longevity genes then healthy living needs to be a daily way of life.
My grandfather grew up in Edinburgh, survived two world wars and made it healthily into his nineties. He taught me a lot, but probably his biggest lesson was not to take anything too seriously. Stress can switch off our healthy genes and his jovial approach to life probably kept many of his switched on. This may have been why, at the age of 91 he was still a menacing bowler in our back garden cricket matches.
In Britain today, one baby in three will reach their 100th birthday. Encouraging though that is, living longer is not a given for everyone, and populations could continue to die younger if governments and people fail to embrace what research is teaching us about health and aging.
But there are things we can each do on a personal level to die “young” as late as possible; to reach 100 in good health. Sleep well, eat better, exercise more, have long been hailed as health clichés, but they remain so for a reason — they work. Keeping the brain active by engaging in a variety of activities, whether it be crosswords, reading, taking up a new hobby, swimming, singing, works the muscles and retains its elasticity. While studies have suggested against ingesting large doses of antioxidants, a good quality multivitamin three times a week helps replace the minerals and vitamins we are not getting from our modern diet.
Last (and not the least cliché of them all) — laughter.