Life expectancy can increase by up to 10 years following sustained shifts towards healthier diets in the United Kingdom

Adherence to healthy dietary patterns can prevent the development of non-communicable diseases and affect life expectancy. Here, using a prospective population-based cohort data from the UK Biobank, we show that sustained dietary change from unhealthy dietary patterns to the Eatwell Guide dietary recommendations is associated with 8.9 and 8.6 years gain in life expectancy for 40-year-old males and females, respectively. In the same population, sustained dietary change from unhealthy to longevity-associated dietary patterns is associated with 10.8 and 10.4 years gain in life expectancy in males and females, respectively. The largest gains are obtained from consuming more whole grains, nuts and fruits and less sugar-sweetened beverages and processed meats. Understanding the contribution of sustained dietary changes to life expectancy can provide guidance for the development of health policies.


Recruitment
UK Biobank is a prospective cohort study.A total of over 500,000 participants aged 37-73 years at baseline were enrolled, from the general population.In brief, between 2006 and2010, participants attended one of 22 assessment centres across Scotland, England, and Wales.All participants completed a touch-screen questionnaire, had physical measurements taken, and provided blood, urine, and saliva samples at baseline.A subset of 467,354 participants in UK Biobank for whom diet was assessed at least once using the web-based 24-hour dietary questionnaire Oxford WebQ were included in this study (Text S1, Table S1).

Ethics oversight
This study was performed under generic ethical approval obtained by UK Biobank from the National Health Service National Research Ethics Service (approval letter ref 11/NW/0382, 17 June 2011).
Note that full information on the approval of the study protocol must also be provided in the manuscript.

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Life sciences
Behavioural & social sciences Ecological, evolutionary & environmental sciences For a reference copy of the document with all sections, see nature.com/documents/nr-reporting-summary-flat.pdf

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Study description
UK Biobank is a prospective cohort study (quantitative).Our study used modeling with these background data.

Research sample
A subset of 467,354 participants in UK Biobank for whom diet was assessed at least once using the web-based 24-hour dietary questionnaire Oxford WebQ were included in this study (56% females).

Sampling strategy
A population-based random sample from >500,000 participants aged 37-73 years at baseline were enrolled, from the general population.In brief, between 2006 and 2010, participants attended one of 22 assessment centres across Scotland, England, and Wales.All participants completed a touch-screen questionnaire, had physical measurements taken, and provided blood, urine, and saliva samples at baseline.

Data collection
The baseline touchscreen questionnaire that was completed by participants at the assessment centre, was based on the food frequency questionnaire (FFQ), which included 29 items about diet and 18 questions about alcohol.The questionnaire included data on the frequency of consumption of the main food groups over the previous year, including fruits and vegetables, fish, meat, and cheese (details in Table S4).A 24-hour recall-based method, based on the Oxford WebQ, which captured information on up to 206 food and 32 drink items, was introduced towards the end of the recruitment period.Thus, participants recruited between April 2009 and September 2010 completed this at their assessment centre baseline visit.In addition, between February 2011 and June 2012, there were 4 cycles, separated by 3-4 months, where participants were invited via email to complete the 24-hour dietary recall at home.Over 200,000 participants completed at least one 24-hour recall.Further details about the dietary assessments, including

Sampling strategy
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