Researchers have identified eight habits that could see people live more than 20 years longer.

The study found that low physical activity, opioid use, and smoking had the biggest impact on lifespan, and were associated with around a 30-45% higher risk of death.

While stress, binge drinking, poor diet, and poor sleep hygiene were each associated with around a 20% increase in the risk of death.

And a lack of positive social relationships was associated with a 5% increased risk of dying.

Our research findings suggest that adopting a healthy lifestyle is important for both public health and personal wellness

Meanwhile, a separate study suggests incorporating olive oil into your diet could help reduce the risk of dying from dementia.

Consuming more than half a tablespoon of olive oil per day is linked to a 28% lower risk of dying from the condition, compared with those who never or rarely eat the oil, researchers say.

The findings from both studies were presented at Nutrition 2023, the annual meeting of the American Society for Nutrition being held in Boston, and may include more up-to-date figures than the data initially submitted for the meeting.

The research that looked at lifestyle habits used data from medical records and questionnaires collected between 2011-2019 from 719,147 people enrolled in the Veterans Affairs Million Veteran Program.

It found that men who have all eight habits at age 40 would be predicted to live an average of 24 years longer than men with none of these habits, and for women an additional 21 years.

Xuan-Mai Nguyen, health science specialist at the Department of Veterans Affairs and rising fourth-year medical student at Carle Illinois College of Medicine, USA, said: “We were really surprised by just how much could be gained with the adoption of one, two, three, or all eight lifestyle factors.

“Our research findings suggest that adopting a healthy lifestyle is important for both public health and personal wellness.

“The earlier the better, but even if you only make a small change in your 40s, 50s, or 60s, it still is beneficial.”

The researchers say their findings, which have not been peer-reviewed, highlight the role of lifestyle factors in contributing to chronic diseases such as type 2 diabetes and heart disease that lead to premature disability and death.

In the olive oil study scientists analysed dietary questionnaires and death records collected from more than 90,000 Americans over three decades, during which 4,749 people died from dementia.

It also found that replacing just one teaspoon of margarine and mayonnaise with the equivalent amount of olive oil per day was associated with around an 8-14% lower risk of dying from dementia.

Anne-Julie Tessier, a postdoctoral fellow at the Harvard TH Chan School of Public Health in the USA, said: “Our study reinforces dietary guidelines recommending vegetable oils such as olive oil and suggests that these recommendations not only support heart health but potentially brain health, as well.

“Opting for olive oil, a natural product, instead of fats such as margarine and commercial mayonnaise is a safe choice and may reduce the risk of fatal dementia.”

Research suggests that people who regularly use olive oil instead of processed or animal fats tend to have healthier diets overall.

However, Dr Tessier noted that the relationship between olive oil and the risk of dying from dementia in this study was independent of overall diet quality.

She added that the research is observational and does not prove olive oil is the cause of the reduced risk of fatal dementia.

However, Professor David Curtis, UCL, said it was difficult to assess whether the research adds much to the understanding of links between diet, health and dementia risk, as it has not been peer-reviewed.

He added: “There are many, many differences between people who consume olive oil and those who do not and it is never possible to fully account for all possible confounding factors.

“Another point to bear in mind is that about half of dementia is caused by vascular disease so that anything which improved cardiovascular health, such as not smoking, would be expected to reduce dementia risk.

“It has been shown that olive oil consumption is associated with better cardiovascular health so one would expect that it would also be associated with lower dementia risk.”

Dr Duane Mellor, registered dietitian and senior lecturer, Aston University, said: “The authors claim replacing margarine and mayonnaise with olive oil could reduce risk.

“However, many people who did this would also change the food that it is being added to, which could increase vegetable, lentils, beans, peas, seeds and nut intake – all of which are linked to a healthy diet and reduced risk of conditions like dementia.

“We also need to remember that it is not just what we eat that helps maintain our brain function, it is how we eat – and remaining sociable around meal times and eating with others can benefit our mental health in the short term and cognitive function as we age.”