The study came as part of the multi-centre project 'European Study to Establish Biomarkers of Human Ageing' (MARK-AGE), which was funded by the European Commission.
The researchers said in the past studies had looked into this topic on a smaller scale with less stratified populations and narrower age groups and did not include both men and women.
These papers have also largely been carried out in the US where eating habits differ Europe.
The MARK-AGE paper included 2,118 women and men age-stratified from 35 to 74 years in six different EU countries.
The researchers said links between the lower risk of major chronic age-related diseases like cardiovascular diseases, diabetes and cancer and diets high in fruit and vegetables had led to an increased interest in the influence of carotenoid- and antioxidant-rich diets on the ageing process.
The researchers found that age was inversely associated with lycopene and alpha-carotene levels but positively with alpha-tocopherol in both women and men.
“These relations hold true after adjusting for well-known factors affecting plasma concentrations of carotenoids and tocopherols such as season, country, smoking status, gender, use of vitamin supplements, and intake of fruit, and vegetables,“ they wrote in the journal Nutrients.
They said the lower plasma levels of lycopene and alpha-carotene as we age may be down to several reasons including changes in dietary habits, lifestyle, impaired bioavailability of nutrients, storage pattern and an increased demand of antioxidants in later life.
You are what you eat
Using food diaries, they found intake of fruit, vegetables and vitamin supplements were all significantly higher for women than men and for non-smokers compared to smokers.
For reported vitamin supplement use of at least once a week this stood at 22% of women compared to 17% of men and 21% for non-smokers compared to 15% of smokers.
The reported use of these supplements differed between countries, with 24% of Germans taking them at least once a week compared to 23% in Poland, 23% in Austria, 19% in Belgium, 15% in Italy and just 14% in Greece.
Overall daily consumption of fruit and juice were higher and the weekly meat consumption was lower the older the participants were.
This also differed according to country.
Fruit consumption was high in Italy and Belgium where 78% and 66% of subjects, respectively, said they ate at least one serving each day.
Meanwhile 80% of Italians also said they ate at least one portion of vegetables per day and this was also high in Belgium at 85%.
French fries were frequently eaten in Belgium (40% of subjects reporting at least one serving per week) and in Greece (26%), and meat consumption (at least one serving per day) was high in Poland (30% of subjects) and Belgium (22% of subjects).
In the blood
Breaking these intakes down to nutrient plasma levels, the researchers found the highest mean concentrations of plasma carotenoids for lycopene.
Apart from beta-carotene, all carotenoids, tocopherols and retinol were statistically significantly associated with age.
Lycopene and alpha-carotene were inversely correlated with age, whereas beta-cryptoxanthin, lutein, zeaxanthin, alpha-/ gamma-tocopherol and retinol were positively linked with age.
The highest mean lycopene concentrations were found in subjects from Belgium, Greece and Italy, which reflected the high fruit, vegetable and French fries consumption in these countries.
Multi-centre EU team
The research was conducted by various institutions, mainly based in Germany: the University of Hohenheim, Friedrich-Schiller-University, the Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), German Center for Diabetes Research (DZD), German Center for Cardiovascular Research (DZHK), NutriAct-Competence Cluster Nutrition Research Berlin-Potsdam, University of Konstanz and research firm BioTeSys.
Elsewhere researchers came from the Dutch National Institute of Public Health and the Environment (RIVM), the Leipold-Franzens-University and University for Health Sciences in Austria, the University of Namur in Belgium, the Greek Institute of Biological Research and Biotechnology and National Hellenic Research Foundation (NHRF), the University of Bologna in Italy and the Polish Academy of Sciences.
8(10), 614; doi: 10.3390/nu8100614
“Plasma Carotenoids, Tocopherols, and Retinol in the Age-Stratified (35–74 Years) General Population: A Cross-Sectional Study in Six European Countries”
Author: W. Stuetz, D. Weber, M. E. T. Dollé, E. Jansen, B. Grubeck-Loebenstein, S. Fiegl, O. Toussaint, J. Bernhardt, E. S. Gonos, C. Franceschi, E. Sikora, M. Moreno-Villanueva, N. Breusing, T. Grune and A. Bürkle