Evaluating the potential health gain of the World Health Organization's recommendation concerning vegetable and fruit consumption

Abstract

OBJECTIVE: The World Health Organization (WHO) recommends a daily intake of at least 400 g of vegetables and fruit. The aim of this paper was to evaluate the public health benefit of meeting this WHO recommendation by applying a statistical method that combines estimated intake distributions and simulated intake changes. DESIGN AND SETTING: The benefit of an increased consumption of vegetables and fruit was quantified by the preventable proportion of diseases. This proportion was estimated by a general formula derived in the paper that incorporates individual relative risks. Three different strategies of increasing usual intake were simulated and compared. The first strategy assumes that all individuals increase their intake by the same amount, the second assumes a constant increase among low consumers, and the third simulates individual increments necessary to meet the WHO recommendation. Calculations were made for three different scenarios with varying relative risks. RESULTS: The third simulation strategy turned out to be the most appropriate one to quantify the potential health gain of the current dietary recommendation. Applying this strategy to prevent cancer, the proportion of preventable cases was country-specific. Estimates for France and Sweden were 21.9% and 19.3%, respectively, which are somewhat lower than the non-specific figure published by the World Cancer Research Fund. CONCLUSIONS: To improve estimates of the preventable proportion of diseases, the estimation formula presented here can be applied. Its application requires intake data to estimate the initial intake distribution in the population and to simulate adequate dietary changes.