We may not need to completely overhaul our lives to live healthier for longer, according to a large UK-based study.

This is welcome news, particularly as many people will already have abandoned their New Year’s resolutions.

The recent study followed about 590,000 people in Britain, with an average age of 64, over an eight-year period. The researchers confirmed earlier findings that healthier lifestyles are associated with lower risk of disease, including dementia, and with living longer in good health and independence.

The authors reported that even very small changes were associated with such benefits. These included about five additional minutes of sleep a night, two extra minutes a day of moderate to vigorous physical activity, and modest improvements in diet. Together, these changes were associated with roughly one additional year of healthy life. “Healthy life” here refers to years lived without major illness or disability that limits daily functioning.

More substantial changes were linked to larger gains. Almost half an hour of extra sleep a night, combined with four additional minutes of exercise a day, which adds up to nearly half an hour of extra activity a week, along with further dietary improvements, was associated with up to four additional healthy years of life.

This matters because, although women live longer on average than men, those extra years are often spent in poorer health, with significant personal and economic costs. Women face a higher risk of dementia, stroke and heart disease at older ages, as well as conditions that lead to vision loss and bone fractures. These illnesses can reduce quality of life and threaten independence.

Lifestyle change may also reduce the risk of early death. The same lifestyle factors examined in this cohort were analysed last year in a separate study, which focused on mortality (the risk of dying).

In that analysis, people who followed healthier lifestyle patterns over an eight-year period had a 10 per cent lower risk of death in that period. The combination of 15 extra minutes of sleep a night, two additional minutes of moderate to vigorous physical activity a day and a healthy diet was linked to a modest reduction in the risk of dying.

A much larger reduction of 64 per cent was seen among people who slept between seven and eight hours a night, ate a healthy diet and engaged in 42-103 additional minutes of moderate to vigorous physical activity every week. Importantly, this benefit was seen only when these behaviours occurred together. Diet alone had no measurable effect, for instance.

Strengths and limitations

One of the key strengths of these studies is that they show health benefits at very low thresholds of behaviour change. This reduces the likelihood that the results are driven only by people who are already healthier or more motivated, and makes the findings more applicable to older adults and those with limited capacity to change their routines.

Another strength is the use of objective measurements rather than self-reported data. Physical activity and sleep were measured using wearable devices, rather than relying on participants to estimate their own behaviour. Self-reporting can be unreliable, particularly for people with memory problems, such as those in the early stages of dementia.

However, there are important limitations. The objective measurements were collected only for three to seven days, which may not reflect people’s long-term habits. From personal experience, wearing activity trackers can lead people to exercise more while they are being monitored, but these changes are often short-lived.

In addition, wrist-worn accelerometers estimate sleep and activity based on movement. During deep sleep, people move very little, but lack of movement does not always mean someone is asleep. These devices may therefore not fully capture true sleep patterns or physical activity levels. Other methods, such as thigh-mounted sensors or mattress-based sensors that detect movement during sleep, may provide more accurate assessments.

Despite these issues, objective measurements are generally more reliable than self-report. Still, because behaviour was only measured once, it is unclear whether actual changes in behaviour over time influenced health outcomes. It is also not clear whether the recorded activity reflected leisure-time exercise or physical activity at work, which can have different effects on health.

Dietary information presents another challenge. Diet was self-reported and collected three to nine years before collection of sleep and activity data. Diets often change over time, particularly after diagnoses such as cardiovascular disease, where people may be advised to reduce their cholesterol intake, or in conditions such as dementia, where people may forget to eat. As a result, it is difficult to know whether diet influenced disease risk, or whether emerging disease altered diet, eventually contributing to poor health and earlier death.

There are also broader social factors to consider. Healthy behaviours tend to cluster together and are strongly linked to education and financial security. For example, smoking and having overweight and obesity are closely associated with deprivation and poverty.

Participants in the UK Biobank, a large long-term health research project that collects genetic, lifestyle and health data from hundreds of thousands of British adults, are generally healthier than the average British population.

Health research often attracts people who are healthier, better educated and more financially secure. This may reflect both interest in research and having the time and resources to take part in such studies.

Wealth also shapes exposure to risk. People with higher incomes are less likely to live in areas with high levels of pollution and are more likely to have control over their working conditions and finances. Financial stress can affect sleep quality, leading to fatigue and reducing the likelihood of exercising, shopping for fresh food, or preparing healthy meals. Over a lifetime, these factors contribute to poorer health and earlier death.

Although researchers attempted to account for these influences using statistical methods, these are deeply interconnected and difficult to separate. The widening health-wealth gap, with many people now living in severe poverty, highlights the limits of personal responsibility. These structural issues require action from policymakers, rather than placing the burden solely on people who may have very little control over the conditions that shape their health.

Eef Hogervorst, Professor of Biological Psychology, Loughborough University

This article is republished from The Conversation under a Creative Commons licence. Read the original article.