- Posted April 1, 2014 by
London, United Kingdom
Seven plus portions of fruits and veggies reduce all-cause mortality
Fruits and vegetables are an important part of a healthy diet and adequate daily consumption could help prevent major diseases, such as cardiovascular diseases and certain cancers.
In a new analysis of health survey for England, researchers from the University College London led by Dr. Oyinlola Oyebode of UCL's Department of Epidemiology & Public Health examined whether daily consumption of fruit and vegetables benefits health in the general population of England.
For this analysis researchers evaluated lifestyle data of 65,226 participants, aged 35 years and up in the 2001–2008 Health Surveys for England. The Health Survey for England is a major monitoring tool looking at the nation's health. It is used by the Government to plan health services and make important policy decisions that have an impact on us all.
The participants were visited by an interviewer who collected demographic and socioeconomic data, health and health-related behaviors, measures on their height and weight, and even had a nurse to take waist circumference, blood pressure, blood samples, and medication use.
The results showed that participants who consumed seven or more servings of fruits and vegetables were less likely to die from any cause over almost an eight year span. Consuming seven or more servings reduced cancer mortality by 25% and cardiovascular mortality by 31%.
For those participants who consumed less than seven servings a day still saw benefits but they were not as strong. Consuming five to seven servings reduced mortality by 36%, three to five servings 29% and one to three servings 14%.
These figures are adjusted for sex, age, cigarette smoking, social class, Body Mass Index, education, physical activity and alcohol intake, and exclude deaths within a year of the food survey.
Fresh vegetables had the strongest effect with each daily portion reducing overall risk of death by 16%. Salad contributed to a 13% risk reduction per portion, and each portion of fresh fruit was associated with a smaller but still significant 4% reduction.
Dr. Oyebode comments "We all know that eating fruit and vegetables is healthy, but the size of the effect is staggering.” "The clear message here is that the more fruit and vegetables you eat, the less likely you are to die at any age. Vegetables have a larger effect than fruit, but fruit still makes a real difference. If you're happy to snack on carrots or other vegetables, then that is a great choice but if you fancy something sweeter, a banana or any fruit will also do you good."
The findings lend support to the Australian government's 'Go for 2 + 5' guidelines, which recommend eating two portions of fruit and five of vegetables. The UK Department of Health recommends '5 a day', while 'Fruit and Veggies – More Matters' is the key message in the USA.
“Our study shows that people following Australia's 'Go for 2 + 5' advice will reap huge health benefits," says Dr Oyebode. "However, people shouldn't feel daunted by a big target like seven. Whatever your starting point, it is always worth eating more fruit and vegetables. In our study even those eating one to three portions had a significantly lower risk than those eating less than one.”
There was no evidence found for fruit juice but canned and frozen fruit seemed to increase the risk of mortality by 17% for each portion. The survey did not distinguish between canned and frozen fruit so this finding is difficult to interpret. Canned fruit products are almost four times more popular than frozen fruit in Europe*, so it is likely that canned fruit dominated this effect.
Dr. Oyebode explains "Most canned fruit contains high sugar levels and cheaper varieties are packed in syrup rather than fruit juice.” "The negative health impacts of the sugar may well outweigh any benefits. Another possibility is that there are confounding factors that we could not control for, such as poor access to fresh groceries among people who have pre-existing health conditions, hectic lifestyles or who live in deprived areas."
In their conclusion the researchers write “A robust inverse association exists between fruit and vegetable consumption and mortality, with benefits seen in up to 7+ portions daily. Further investigations into the effects of different types of fruit and vegetables are warranted.”
*Note: 13.0m tons of canned fruit and vegetables were sold in the EU in 2008 compared to 3.7m for frozen fruit and vegetables. See CBI Market ‘Survey The EU Market for Canned Fruit and Vegetables and Preserved Fruits and Vegetables The EU market for frozen fruit and vegetables.
This is the first study to link fruit and vegetable consumption with all-cause, cancer and heart disease deaths in a nationally-representative population, the first to quantify health benefits per-portion, and the first to identify the types of fruit and vegetable with the most benefit.
This study is published in the Journal of Epidemiology & Community Health.