Eat your greens: fruit and vegetables cut disease risk

Chronic non-communicable diseases (NCDs) are the leading causes of death and disability worldwide and are increasing rapidly in most regions. Meanwhile, the traditional plant-based diet in many countries is being replaced by a diet rich in animal fats and sugar and low in fibre. An analysis of international data helps to clarify the link between these two trends.

The degree of protectiongiven by fruit and vegetables against cardiovascular disease and cancers isunclear. Researchers from the London School of Hygiene and Tropical Medicineanalysed data from the updated World Health Organisation (WHO) Global Burden ofDisease (GBD) project, which included fruit and vegetable consumption as one of26 risk factors. They found that consumption is highest in Western Europe andparts of Australasia, and lowest in North America, the Former Soviet Union,parts of South-East Asia and eastern and southern Africa. Consumption varies byage, with children and the elderly generally having eating less thanmiddle-aged adults.

The analysis also showedthat:

• Inadequateconsumption of fruit and vegetables is estimated to cause up to 2.635 milliondeaths per year worldwide.
• Increasingindividual intake by up to 600g per day could reduce the total worldwide burdenof disease by 1.8 percent.
• This compareswith 1.3 percent for physical inactivity, 2.3 percent for overweight andobesity, 2.8 percent for high cholesterol and 4.1 percent for tobacco use.
• The increasedintake would reduce the burden of ischaemic heartdisease and ischaemic stroke by 31 percent and 19percent, respectively.
• For stomach,oesophageal, lung and colorectal cancer, the potential reductions are 19, 20,12 and two percent, respectively.

The researchers warn that theimpact of fruit and vegetable consumption on disease risk may vary depending onthe type and combination eaten, the frequency, and changes in intake during alifetime. It is also unclear whether the benefit of eating more fruit andvegetables is linear or whether there is a minimum threshold intake required.

Despite the limitations ofthe GBD study, it provides information on the impact of 26 risk factors,obtained using uniform methods, for all world regions. It can be used to stimulatedecision-makers to think about a wider range of health determinants whendeveloping public policy. In particular, they should consider:

• placing nutritionmuch higher on the policy agenda addressing the increasing rates of NCDs worldwide
• promoting an increasein fruit and vegetable intake to 400-500g per day (as in ‘5-a-day’ campaigns insome countries) as a minimum goal
• tacklingcompeting pressures such as marketing of fast food
• looking beyondindividual behaviour change, aiming to enhance people’s ability to eat healthydiets through action on agriculture, food labelling, nutritional claims,advertising, nutrition programmes and food taxation
• supporting the joint Fruit and Vegetable Promotion Initiative ofthe WHO and the UN Food and Agriculture Organisation (FAO), which advocates thedevelopment and implementation of national policies that are sustainable,comprehensive and engage all sectors.