Positive Health Online

Abstract

MYINT and COLLEAGUES, 1 School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK. phyo.myint@abdn.ac.uk ;  2 Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, UK phyo.myint@abdn.ac.uk ;.3 Clinical Gerontology Unit, Department of Public Health and Primary Care, School of Clinical Medicine, University of Cambridge, Cambridge, UK. phyo.myint@abdn.ac.uk ;4 Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, UK; 5 Clinical Gerontology Unit, Department of Public Health and Primary Care, School of Clinical Medicine, University of Cambridge, Cambridge, UK.6 MRC Epidemiology Unit, Cambridge, UK set out to quantify the association between plasma vitamin C concentrations as an indicator of high fruit and vegetable consumption and the risk of incident respiratory diseases and associated mortality in a general population.

Background

Cancerous and non-cancerous respiratory diseases are common and contribute significantly to global disease burden. The authors aimed to quantify the association between plasma vitamin C concentrations as an indicator of high fruit and vegetable consumption and the risk of incident respiratory diseases and associated mortality in a general population.

Methodology

Nineteen thousand three hundred and fifty-seven men and women aged 40-79 years without prevalent respiratory diseases at the baseline (1993-1997) and participating in the European Prospective Investigation into Cancer (EPIC)-Norfolk study in the United Kingdom were followed through March 2015 for both incidence and mortality from respiratory diseases.

Results

There were a total of 3914 incident events and 407 deaths due to any respiratory diseases (excluding lung cancers), 367 incident lung cancers and 280 lung cancer deaths during the follow-up (total person-years >300,000 years). Cox's proportional hazards models showed that persons in the top quartiles of baseline plasma vitamin C concentrations had a 43% lower risk of lung cancer (hazard ratio (HR) 0.57; 95% confidence interval (CI): 0.41-0.81) than did those in the bottom quartile, independently of potential confounders. The results are similar for any non-cancerous respiratory diseases (HR 0.85; 0.77-0.95), including chronic respiratory diseases (HR 0.81; 0.69-0.96) and pneumonia (HR 0.70; 0.59-0.83). The corresponding values for mortality were 0.54 (0.35-0.81), 0.81 (0.59-1.12), 0.85 (0.44-1.66) and 0.61 (0.37-1.01), respectively. Confining analyses to non-smokers showed 42% and 53% risk reduction of non-smoking-related lung cancer incidence and death.

Conclusion

Higher levels of vitamin C concentrations as a marker of high fruit and vegetable consumption reduces the risk of cancerous and non-cancerous respiratory illnesses including non-smoking-related cancer incidence and deaths.

References

Phyo Kyaw Myint  1   2   3 , Andrew M Wilson  4 , Allan B Clark  4 , Robert N Luben  5 , Nicholas J Wareham  6 , Kay-Tee Khaw  5. Plasma vitamin C concentrations and risk of incident respiratory diseases and mortality in the European Prospective Investigation into Cancer-Norfolk population-based cohort study. Eur J Clin Nutr.;73(11):1492-1500. Nov 2019. doi: 10.1038/s41430-019-0393-1.Jan 31 Epub 2019.

 

Comment

The results of the above cohort study comprising >19,000 individuals demonstrate  a 43% lower risk of death from lung cancer and 53% from death in people with high plasma vitamin C concentrations serving as marker of high fruit and vegetable consumption.