(CNN) — Small changes in diet, exercise and sleep may extend life by a year when put into practice together, while making larger changes could provide more than nine additional years of life, according to a new study.
Combining changes in diet, sleep and exercise also increased “health span,” or the number of years a person may live without major health complaints.
“These findings highlight the importance of considering lifestyle behaviors as a package rather than in isolation,” said lead study author Nick Koemel, a research fellow in physical activity, lifestyle and population health at the University of Syndey’s main campus in Camperdown, Australia.
“By targeting small improvements across multiple behaviors simultaneously, the required change for any single behavior is substantially reduced, which may help overcome common barriers to long-term behavior change,” Koemel said in an email.
However, that finding is far from conclusive, said Kevin McConway, professor emeritus of applied statistics at the Open University in Milton Keynes, United Kingdom, who was not involved in the study.
“A snag is that the paper uses complicated statistical methods that are not always described clearly,” McConway said in an email. “It’s therefore difficult to tell to what extent the findings have emerged from the researchers’ choice of statistical analyses, rather than things that are clearer from the data.”
A theoretical model
Using scientific modeling, Koemel and his team found combining as little as five additional minutes of sleep, two minutes of moderate to vigorous physical activity (such as brisk walking or taking the stairs), and an additional ½ cup of vegetables a day might lengthen life by a year.
However, this predicted outcome was only for people who had an extremely poor diet, slept less than six hours per night and only exercised about seven minutes a day. In addition, it wasn’t until the model’s lifestyle improvements greatly increased that the results became scientifically significant.
“All of the gains reported in this study are theoretical,” Koemel said. “We cannot claim a direct causal effect from the lifestyle patterns. These findings should therefore be interpreted as expected or projected benefits under assumed behavioral variations, rather than confirmed effects of an intervention.”
The greatest gain in longevity — 9.35 years — and health span — 9.46 years — came with the combination of an addition of 42 to 103 minutes of exercise and sleeping between seven and eight hours a day, while also eating an extremely healthy diet that included fish, whole grains, vegetables and fruits.
Adding exercise to the mix moved the longevity needle the most — a fact that did not surprise preventive cardiologist Dr. Andrew Freeman, director of cardiovascular prevention and wellness at National Jewish Health in Denver.
“Exercise is the elixir of youth,” said Freeman, who was not involved in the study. “But let me be clear — this study should not be interpreted as exercising for exactly two minutes and stop, you’ve accomplished a goal.
“Rather, you should aim to get 20 to 30 minutes of brisk, breathless physical activity, combining strength and cardio in every day. That advice has not changed over decades of study.”
Forget numbers — focus on well-being
The study, published Wednesday in the journal eClinicalMedicine, looked at almost 60,000 participants from England, Scotland and Wales in the UK Biobank, a longitudinal health study, who were followed for an average of eight years. Everyone in the study provided information on their diet — including ultraprocessed foods, such as sugar-sweetened beverages. A subset of the group also wore wrist watches that provided more objective measurements of movement and sleep.
Researchers gathered this medical data and used it to form theoretical scenarios of improved longevity and health span, which was defined as the number of years free of cardiovascular disease, dementia, chronic obstructive pulmonary disease and type 2 diabetes.
Enjoying a longer life and a longer health span, or remaining free of disease, aren’t the same thing, Koemel said. “Combined improvements in sleep, physical activity, and diet were associated with longer lifespans, even if people still developed some chronic conditions later in life.”
After adjusting the findings for many variables — such as the amount of ultraprocessed foods, smoking, alcohol use, body mass index, insomnia, snoring and daytime sleepiness — the results differed depending on how much of each behavior change was accomplished.
In addition to the lowest and highest levels of the lifestyle changes discussed above, researchers also found lower levels of exercise — less than 23 minutes a day — sleeping seven to eight hours a night, and an excellent diet were associated with nearly four more years of life and three years of health, the study found.
Moderate levels of exercise (between 23 and 42 minutes a day), sleeping up to eight hours per night, and a high-quality diet were associated with a greater improvement of an additional seven years of life and just over six years of good health. So many calculations! What does it all mean?
“This is not about the absolute minutes you exercise or sleep or the number of pieces of broccoli you eat. It’s about making sure that all the things you do in your life are synonymous with health,” Freeman said.
“This is a great time of year to reflect on how you live and make big changes that will set you up for a life of wellness by modifying your life’s trajectory,” he said. “The overall signal in the noise is if you live well, your health span and then your lifespan will be longer.”