Rethinking realistic serving targets for fruit, vegetables and legumes

29 Aug 2017 --- Contrary to the often cited five-a-day, a new study among more than 135,000 people in 18 countries has found that eating three to four servings of fruit, vegetables and legumes per day (375-500g) achieves a similar benefit against the risk of mortality to higher portions. The findings provide a more affordable option for those in low- and middle-income countries and may have significant implications on household spending and food security in poorer countries.

The study takes a new approach to looking at the intake of fruit, vegetables and legumes and their association with cardiovascular disease and mortality on a global scale and includes data from 18 countries.

The authors stress that intake of fruit, vegetables and legumes should be considered part of a healthy diet. Global dietary guidelines, like those of the World Health Organization (WHO), recommend eating five servings of fruit, vegetables or legumes a day (equivalent to minimum 400g), but these targets are unaffordable for most people in low- and middle-income countries. 

The study suggests that three to four portions amounting to 375-500g could be just as beneficial. The authors do not recommend changes for people in high-income countries who can afford fruit, vegetables and legumes, but suggest that, for people who live in low- and middle-income countries, this provides an approach that is likely to be more affordable for people in these regions.

“Current dietary guidelines may not be achievable globally since fruits and vegetables have been shown to be unaffordable in many low- and lower-middle income countries. Our findings suggest an approach that is likely to be more affordable in lower and middle-income countries – that three to four servings of fruit, vegetables and legumes per day show a similar benefit against reducing the risk of death to ‘five-a-day’ guidance,” says lead author Victoria Miller, McMaster University, Canada. “For people in higher income countries already eating five servings per day, this is not a suggestion to eat less. Fruit, vegetable and legume intake should be seen as a part of an overall healthy diet and lifestyle.”

The study included 135,335 people aged 35-70 years old from 18 countries from various geographic regions including the Middle East, South America, Africa and South Asia. At the beginning of the study, participants provided information on their socioeconomic status, lifestyle behaviors, medical history, family history of cardiovascular disease, weight, height, waist and hip measurements and blood pressure.

They also completed a questionnaire on the types and frequency of food and beverages that they regularly ate, which the researchers used to calculate the number of servings of fruits, vegetables and legumes. In the study, one portion was defined as 125g of fruits or vegetables, or 150g of cooked legumes (as per US Department of Agriculture recommendations), whereas the WHO defines one portion at 80g. Potatoes, other tubers (i.e., sweet potato, cassava and dahlias), and juices were not included as a portion of fruit or vegetables. Legumes included beans, black beans, lentils, peas, chick peas and black-eyed peas.

Participants’ completed follow-up visits with the research team at least every three years to record information on cardiovascular disease (i.e., fatal and non-fatal heart attacks, stroke and heart failure) and death.

During a median follow-up of 7.4 years, there were 4,784 major cardiovascular events (i.e., deaths from cardiovascular disease, and non-fatal heart attacks, stroke and heart failure), 1,649 deaths from cardiovascular disease and 5,796 total deaths.

The global estimates found that risk of death was most reduced when people ate three to four servings of fruit, vegetables or legumes a day – equivalent to 375-500g.

Among people who ate three to four servings a day, the rate of overall death was 3 percent including 1 percent deaths from cardiovascular disease and 2 percent from non-cardiovascular disease (excluding deaths due to injury). Little additional benefit was found for fruit, vegetable and legume intake beyond that range (up to eight servings a day).

By comparison, for people who ate less than one serving a day, the rates were 8 percent for overall death, including 2 percent from cardiovascular disease and 5 percent from non-cardiovascular, respectively.

The study estimates that the average daily intake of fruits, vegetables and legumes is 3.9 servings – typically including two servings of vegetables, 1.5 servings of fruit and 0.4 servings of legumes. Intake was much higher in North America and Europe, South America and the Middle East, where participants typically ate between five and six servings a day, compared with three to four servings in South Asia, China, Southeast Asia and Africa. Typically those who ate more fruits, vegetables and legumes were more educated and physically active, did not smoke as much and lived in urban areas.

It is being presented at the European Society of Cardiology Congress 2017 and is published in The Lancet.