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

Plain Language Summary

The mortality rate is rising in the United Kingdom (UK) due to the poor quality dietary patterns among the general population. Public Health England and the UK government recommend the population eat a healthy balanced diet based on the Eatwell Guide. Adherence to the Eatwell Guide dietary pattern could reduce the mortality rate among the general population in the UK. This research estimated the benefits of sustainably changing the unhealthy dietary pattern to the Eatwell Guide or longevity-associated dietary pattern on life expectancy in the UK. Longevity-associated dietary pattern is based on a moderate consumption of whole grains, fruit, fish and white meat; a substantial consumption of dairy, vegetables, nuts and legumes; a comparatively low consumption of eggs, red meat and sugar-sweetened beverages; and a low consumption of refined grains and processed meat. The unhealthy dietary pattern included limited amounts of whole grains, vegetables, fruits, nuts, legumes, fish, milk and dairy, and white meat and high consumption of processed meat, eggs, refined grains and sugar-sweetened beverages. This peer-reviewed review used prospective population-based cohort data from the UK Biobank. In UK adults aged 40 years, the change from an unhealthy dietary pattern to the Eatwell guide added 8.9 years in males and 8.6 years in females to their life expectancy. Furthermore, sustained adherence to the Eatwell guide increased life expectancy up to 10.8 years in males and 10.4 years in females. Further robust studies are required to evaluate the correlation between life expectancy and different food groups due to the limitations of the current research. However, healthcare professionals can use the results of this research to develop health policies and to understand the beneficial effect of following the Eatwell Guide or longevity dietary pattern in increasing life expectancy in middle-aged men and women in the UK.

Expert Review

Reviewer: Chloe Steele

10th Jun 2024

Conflict of interest

None

Take home message

Healthy diets rich in fresh fruits and vegetables and fibre, and low in processed foods and beverages may help to prolong a healthy life.

Evidence category

C: Non-randomized trials, observational studies, narrative reviews

Summary review

Introduction

Healthy dietary patterns have been shown to reduce mortality. This study aimed to use statistical modelling to determine life expectancy gains following a sustained change from an unhealthy eating pattern to either the Eatwell Guide or the longevity-associated dietary pattern.

Methods

This was a prospective cohort study of over 500,000 individuals aged 37-73.
Statistical modelling (using a method developed by the authors) was used to estimate gains or losses in life expectancy after sustained dietary changes.

Results

Individuals who ate the highest amounts of whole grains (HR= 0.82; 95% CI: 0.79–0.86), vegetables (HR=0.93; 95% CI:0.89–0.97), fruit (HR= 0.86; 95% CI: 0.82–0.9), nuts (HR=0.81; 95% CI 0.2–3.24), legumes (HR=0.72; 95% CI: 0.1–5.11), and milk (HR= 0.93; 95% CI: 0.8–1.08) were associated with a reduced risk of all-cause mortality.
Individuals who ate the highest amounts of eggs (HR= 1.0; 95% CI: 0.95–1.23), red meat (HR= 1.21; 95% CI: 1.08–1.37), processed meat (HR= 1.47; 95% CI:1.27–1.69), refined grains (HR= 1.16; 95% CI: 1.11–1.21), and sugar sweetened beverages (HR= 1.59; 95% CI: 1.1-2.31) were associated with increased risk of all-cause mortality.
Sustained dietary changes from an unhealthy diet pattern to the longevity diet pattern increased life expectancy by 10.4 years for females and 10.8 years for males who were 40 years of age.
This amount decreased if aged 70 but was still 5.4 years for females and 5.0 years for males.
The Eatwell dietary pattern increased life expectancy slightly less than the longevity diet but was shown to increase life expectancy for a 40-year-old by 8.6 years for females and by 8.9 years for males.

Conclusion

It was concluded that middle-aged adults who change from an unhealthy dietary pattern to following the Eatwell Guidelines, or the longevity diet pattern, can increase their life expectancy.
Additional benefits can be seen if the new diet is rich in whole grains and nuts and reduces sugar-sweetened beverages and processed meats.

Clinical practice applications

This study supports the recommendation of healthier eating patterns for longevity.
Diets high in whole grains, nuts, and legumes and low in processed foods may support longevity.
This is however a modelling study and life expectancy increases are an estimate.
The longevity diet pattern differs slightly from the Eatwell Guide in that it has adopted a fasting-mimicking pattern of eating and completely cuts out red meat, which may account for differences in life expectancy increases.

Considerations for future research

Future research should focus on stratifying the associations between mortality and diet by gender and age.

Expert reviews are written by nutrition professionals and academics with advanced qualifications to provide a critical appraisal of the article and implications for practice. Each review is peer-reviewed by a member of the NED Editorial Board. Find out more about our NED Expert Reviewers here.

Abstract

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.