As rich sources of micronutrients, dietary fibre and other favourable substances, such as antioxidants, fruit and vegetables (F&V) are important elements of a healthy and balanced diet. However, population consumption of F&V remains inadequate( Reference Hall, Moore and Harper 1 ), independently increasing the risk of non-communicable diseases such as cardiovascular diseases (CVD), diabetes and several cancers( Reference Zhan, Liu and Cai 2 – Reference Hung, Joshipura and Jiang 8 ). Low F&V consumption is among the top contributors to global death and disability, and estimated to be responsible for approximately 6.7 million deaths worldwide in 2010, compared with 5.1 million in 1990( Reference Lim, Vos and Flaxman 9 ).
Fruit and vegetable intake and supply
As part of a healthy diet, the WHO suggests consuming a minimum of 400 g or five servings of F&V per day to improve overall health and reduce the risk of certain non-communicable diseases( 10 ). Recent evidence suggests that a higher number of servings might increase health benefits even further( Reference Oyebode, Gordon-Dseagu and Walker 11 ). Increasing individual F&V consumption to up to 600 g/d could reduce the global burden of disease by 1·8 %( Reference Lock, Pomerleau and Causer 12 ). The majority of adults globally would have to at least double their current F&V consumption to meet the WHO’s minimum recommendation( Reference Murphy, Barraj and Spungen 13 ). A study using data from 2003 showed that 77·6 % of men and 78·4 % of women from fifty-two mainly low- and middle-income countries consumed less than the minimum recommended five daily servings of F&V( Reference Hall, Moore and Harper 1 ). The determinants of low F&V intake vary and include a strong social gradient( Reference Kamphuis, Giskes and de Bruijn 14 ) and local access and availability( Reference Kamphuis, Giskes and de Bruijn 14 ). Wolnicka et al.( Reference Wolnicka, Taraszewska and Jaczewska-Schuetz 15 ) show in this issue that factors within the family environment such as parents’ dietary habits and F&V availability have a great influence on children’s F&V consumption.
A study using data from 2009 found that the global supply of F&V falls, on average, 22 % (34 % when considering food wastage) short of population needs, and this varies from 58 % to 13 % across low- and upper-middle-income countries. High-income countries appear to have sufficient F&V supply( Reference Siegel, Ali and Srinivasiah 16 ). These large differences between countries may be due to a range of factors, such as producer-end subsidies for other crops, adequacy of distribution systems (increasing F&V wastage), increasing population size, international trade, and the exclusion of subsistence farming and food production from the aforementioned figures.
An estimated F&V supply gap of 34 % and 43 % has been projected for years 2025 and 2050, respectively, with widening gaps between high-/middle-income and low-income countries, if current production levels remain constant( Reference Siegel, Ali and Srinivasiah 16 ).
Strategies to increase fruit and vegetable intake: what works?
The World Cancer Research Fund’s ‘NOURISHING framework of food policies to promote a healthy diet’( Reference Hawkes, Jewell and Allen 17 ) provides a useful structure to identify where action is most needed to increase F&V consumption. The NOURISHING framework focuses on policy efforts to improve the healthiness of food environments. These efforts include offering healthy foods and setting nutrition standards in key settings such as schools, food pricing strategies, food labelling regulations and tougher restrictions on junk food marketing to kids. Policy efforts focusing on food environments hinge upon harnessing supply chains and actions across sectors. Indeed, there is a tension between the need to consume more, on the one hand, and making reasonably priced F&V sufficiently available, on the other.
A lot of countries globally have F&V programmes or schemes in place in schools, some of them for lower socio-economic students only( 18 ). There is evidence that these programmes or schemes work to increase fruit consumption( Reference Schwartz, Henderson and Read 19 , Reference Ovrum and Bere 20 ) and to restrain the consumption of junk food among wealthier children( Reference Brunello, De Paola and Labartino 21 ). Some countries use targeted subsidies for healthy foods, including F&V( 18 ). Australia has implemented a Goods and Services Tax exemption for fresh F&V. Fiji has removed original import and excise duty (set at 5–32 %) on F&V that are not locally grown to promote F&V consumption.
This issue of Public Health Nutrition includes an example at the local level. The New York City Health Department District Public Health Offices distribute ‘Health Bucks’ to farmers’ markets in low-income neighbourhoods. When customers use income support (e.g. Food Stamps) to purchase food at farmers’ markets, they receive one Health Buck worth $US 2 for each $US 5 spent, which can then be used to purchase fresh F&V. According to Olsho et al.( Reference Olsho, Payne and Walker 22 ), greater exposure to Health Bucks was associated with greater awareness of farmers’ markets; increased frequency and amount of farmers’ market purchases; and greater likelihood of a self-reported year-over-year increase in F&V consumption.
Reducing junk food marketing to kids also has potential to improve diets( Reference Boyland and Whalen 23 ). Team FNV (http://www.fnv.com/) is a recent innovative campaign in the USA to market F&V and have F&V taking over the billboards from junk food. F&V claims on food packages are often not regulated under existing regulations or standards. Heller et al.( Reference Heller, Martin-Biggers and Berhaupt-Glickstein 24 ) show in this issue that labels and advertisements for sham fruit foods mislead children with regard to the food’s real fruit content. Wellard et al.( Reference Wellard, Hughes and Tsang 25 ) further suggest that F&V claims should be regulated using nutrient profiling. They found that many products in Australia carried F&V claims and were significantly higher in energy, saturated fat, sugar and sodium than fresh F&V. Marketing these products as a way of meeting F&V intake is misleading.
Moreover, it may contribute to increasing the already important social gradient in nutritional health literacy( Reference Cowburn and Stockley 26 ) and the intake of ultra-processed foods that are high in fat, sugar and/or sodium. There are considerable and widening inequalities( 27 , Reference Bell and Slater 28 ) both in the consumption of healthy diets( Reference Mathieson and Koller 29 ) and in nutrition-related diseases( Reference Stamatakis, Wardle and Cole 30 – Reference Howe, Tilling and Galobardes 33 ). It can be argued that health claims are an effective form of marketing, which is a well-established way of influencing consumer food purchasing and consumption behaviour( Reference Cairns, Angus and Hastings 34 ).
The NOURISHING framework also recommends policy areas focusing on population- and individual-level behaviour change and communication, including information, nutrition advice and counselling. There is mixed evidence that F&V promotion campaigns are useful, with some reviews concluding that 5-a-day and other campaigns are somewhat effective at improving knowledge and awareness of recommended F&V portions as well as purchasing behaviour( Reference Mozaffarian, Afshin and Benowitz 35 , Reference Hawkes 36 ) and others finding modest evidence that campaigns aimed to promote an increase in F&V intake( Reference Rekhy and McConchie 37 ) are effective. Intensive long-term campaigns that communicate simple, unambiguous messages through many different channels and involve the whole family in an interactive way have been found to be most effective.
Nudging to increase F&V consumption has been trialled. Van Kleef et al.( Reference van Kleef, Bruggers and de Vet 38 ) suggest in this issue that children’s vegetable intake can be improved by serving larger portions in smaller-sized pieces. In addition, a study from Peru( Reference Cardenas, Benziger and Pillay 39 ) found that promoting fruit consumption by product placement close to the point of purchase, adding health information and price reduction had a positive effect on fruit purchasing in a university cafeteria, especially in males and non-student adults. Yi et al.( Reference Yi, Kanetkar and Brauer 40 ), however, show that the perception of specific vegetables on taste, healthiness, ease of preparation and cost varies significantly across different consumer segments. This has implications for the development of new approaches to promoting different vegetables.
Grier et al.( Reference Grier, Hill and Reese 41 ) evaluated the feasibility of a 10-week gardening and nutrition education programme for young people and their communities living in a low-income area of Virginia (USA). They found potential for the programme in that it significantly improved self-efficacy around F&V, gardening knowledge and familiarity with food-based dietary guidelines. Grier et al.’s study contributes to strengthening the evidence base on urban gardening programmes( Reference Warren, Hawkesworth and Knai 42 ). Gudzune et al.( Reference Gudzune, Welsh and Lane 43 ) also tested opportunities to improve F&V consumption in a low-income urban setting: they paired urban farms with corner stores for produce distribution, which may be feasible as a new model to increase access to F&V among low-income urban neighbourhoods. This echoes the findings of reviews which highlight the importance of multifaceted approaches to F&V( Reference Knai, Petticrew and Durand 44 – Reference Knai, Pomerleau and Lock 46 ), including active participation of the wider community and hands-on exposure to F&V.
Overall, promising strategies for increasing F&V consumption include community-based multi-component interventions to maximise exposure to F&V, interventions in supermarkets and canteens to make F&V more visible and accessible, F&V programmes in schools, reducing junk food marketing to kids and reducing the price of F&V( Reference Mozaffarian, Afshin and Benowitz 35 , Reference Pomerleau, Lock and Knai 45 , Reference Escaron, Meinen and Nitzke 47 , Reference Glanz, Bader and Iyer 48 ).
Future directions
Existing interventions have led to only small to medium increases in the actual consumption of F&V, which is not sufficient to meet the WHO recommendations. In addition, the supply of F&V is currently not sufficient for everyone to meet existing recommendations. The global nutrition and agricultural communities need to find innovative strategies to increase both the supply of and the demand for F&V to meet population health needs.
Some of the strategies to increase demand for F&V may include: providing fresh F&V for low-income students; creating healthier school food environments; farm-to-institution programmes in schools, hospitals and workplaces; taxes on foods of low nutritional value and subsidies on F&V; stricter controls on marketing for unhealthy foods; supporting community gardens; and providing vouchers to help low-income pregnant women and their infants/young children purchase more F&V. Increasing the supply of F&V needs further consideration and could potentially be achieved through: tackling food loss and waste across the supply chain; adequate distribution systems in low-income countries; reducing producer-end subsidies for other crops; and optimizing international trade. Notably, these strategies range across multiple levels, from local to global, and they will have their best chance at success if there is a shared vision of what needs to be achieved and some coordinated effort towards that end.