You can’t out-run a bad diet, say experts. Getting enough sleep as well as eating a balanced diet are among the lifestyle adjustments we can make to support health and longevity
By Chloe Gray
How do you go about improving your health? If you’re part of the majority, you might sign up to a gym or head out running, with a Public Health England survey from 2021 finding the most popular way people improved their lifestyle was by exercising more.
But with a new study from University College London (UCL) showing that the benefits of exercise don’t counteract the negative impact of a lack of sleep, is it a mistake to put all of our healthy eggs in one basket?
“The glamorisation of working out does mean a lot of people feel like intense exercise is the first port of call, especially with the ‘no pain, no gain’ phrase that’s constantly peddled by the industry,” says Nancy Best, PT and founder of Ladies Who Crunch. “Many people are unable to participate in that and for others, it’s actually an extra strain on their nervous system. Exercise is one way, but certainly not the only way, to improve our health.”
So what other health-improving habits should you start building – and how do they compare to working out?
The UCL research, published last week, had some eye-opening insight into the role of sleep on our health. Researchers found that middle-aged people who exercised regularly but slept badly faced the same or more rapid cognitive decline over the course of 10 years as their more sedentary counterparts. The study seemed to reveal that those who slept for six or fewer hours couldn’t reap the benefits of their workouts.
“Good sleep supports us in everything we do,” says sleep scientist Dr Kat Lederle. “It strengthens our immune system to fight off illnesses better and supports our cardiovascular health to lower the risk of heart and metabolic diseases and helps to clear, refill and restore the brain and body.
“Exercise can do this too, but what the current study suggests is that, at least for some age groups, the positive effects of activity can only go so far if sleep is short. ”
“When we are tired we find it harder to engage in healthy behaviours because of how lack of sleep impacts our decision-making and willpower,” adds Dr Lederle.
In fact, 35 per cent of people cite a lack of sleep as the reason they don’t eat well or exercise, according to a survey by the World Cancer Research Fund. “Sometimes, it’s much better to sleep in than to compromise your sleep time for the sake of an intense workout,” adds Dr Lederle.
Can you out-run a bad diet? It seems not, according to a study published in the British Journal of Sports Medicine involving 360,000 people for 11 years, which found high levels of physical activity don’t counteract the detrimental effects of a poor diet on mortality risk.
While people who regularly exercised but had a diet low in fruit and vegetables and high in red and processed meat did live longer than those who ate poorly and did no exercise, those with the best diet and a good exercise routine were the most likely to live longer.
The authors of the study say: “Both regular physical activity and a healthy diet play an important role in promoting health and longevity. Some people may think they could offset the impacts of a poor diet with high levels of exercise or offset the impacts of low physical activity with a high-quality diet, but the data shows that unfortunately, this is not the case.”
Dietitian Sophie Medlin adds: “You won’t be able to benefit from exercise in the same way, build muscle or sustain your workout routine without improving your diet. Combining the two is certainly important but when it comes to weight loss, a calorie deficit is achievable through diet alone.”
In fact, exercise bolsters metabolism which can make us hungrier, so extra exercise often isn’t the route to losing weight, if that is your goal.
“Weight loss aside, our diet is at the core of our overall health. The way that we eat impacts every cell in the body, from its physical structure to its function, making it pivotal for improving health and maintaining good health as we age,” adds Medlin.
There’s more to a good diet than just vegetables and protein – eating a fibre-rich, gut-healthy diet is crucial for supporting health markers, including immunity and mental health.
Harvard University’s infamous Study of Adult Development – which has been ongoing for 85 years, making it the longest in-depth longitudinal study on human life ever done – found the key to longevity isn’t regular exercise or eating salads, but happiness.
Study director, Dr Robert Waldinger, says in his TEDX Talk: “The clearest message we get from this… study is this: Good relationships make us happier and healthier. Period.”
Loneliness kills: some studies have compared it to smoking and countless others have found associations with all-cause mortality. Another study investigating 28,000 people in China found that weekly socialising increased time to death by 110 per cent.
“Researchers aren’t completely sure of the mechanisms that make social connection vital to our health,” explains personal trainer and trainee psychologist Shona Vertue.
“The same regions of the brain involved in physical pain also respond to social rejection, showing our nervous system values relationships and social cohesion because they are incredibly important for our survival and reproduction. In terms of physical health, good relationships reduce stress which we know has a profound impact on our immune and cognitive function.”
So how do you work on your social fitness? “Find relationships that align with your personal values and where interactions leave you feeling good, rather than anxious. Good social engagements also encourage positive behaviour like exercise or skill development,” says Vertue.
“By now, you’ve probably gotten the message that being sedentary sets you up for all kinds of problems, dying prematurely being the worst of them,” write movement experts Juliet and Kerry Starrett in their new book, Built To Move. “But somehow that message has been translated into the idea that if you pedal your heart out for an hour at SoulCycle or on your Peloton bike, you’ve conquered the sedentary dilemma.”
That’s not how it works – in fact, many people who hit the recommended three-to-five-times-weekly workouts are actually considered sedentary because of how irregularly they move. Studies suggest moving more often is more important than moving intensely, with a 2018 review of data on more than 1.3 million people finding that, regardless of exercise, the amount of time sat down a day is associated with a greater risk of several major chronic diseases, including cancer and diabetes. In short, if you sit for 12 hours “you’re in some ways cancelling out all the good your workouts are doing,” say the Starretts.
The first thing you can do to reduce the impact of sedentary behaviour is walking more – specifically 8,000 steps a day which has been associated with a 51 per cent reduction in mortality as well as improved circulation, mental health and body function.
The second is to break up “marathon sitting” by moving every 30 minutes, even with an activity as simple as standing up. A 2016 study reported that 10-30 minutes of standing after meals reduced blood glucose by 12 per cent while walking reduced them by 24 per cent.
“By design, we’re meant to be in motion all day, not necessarily in grand gestures like an hour in the pool or on a running path, but by frequently changing positions [and] adjusting the body’s load,” write the Starretts. “The best way to continue working movement into your life is to stand for a greater proportion of your day. Standing is where the action is.”