HOW MUCH WATER
and women should drink respectively 2 L/day and 1.6 L/day. Each European country is encouraged to include and adapt those recommendations into their official national dietary guidelines [2]. Some countries—such as Spain, the United Kingdom and Turkey—have already incorporated the recommendations [9-11]; yet, still national dietary guidelines might benefit from a revision. For instance, in France the official dietary guidelines are to drink water ad libitum (i.e., without restraint or limit), which could be open to interpretation by the general public [12].
Emerging Science for More Specific Water Recommendations Adapting an international recommendation to one country might be challenging due to the fact that drinking and eating habits of individuals are specific to each culture. When EFSA reviewed the available data on water/fluid intake in 2010, it observed great discrepancy in mean total fluid intake across countries in Europe [2,13,14]. Ideally, each country should make an accurate assessment of total fluid intake in a sample representative of its population. Scientists at Danone Nutricia Research wished to address this gap in the scientific literature by building and publishing on the Liq.In7 database. This database contains information on the drinking habits of populations in 13 countries across three continents: Japan, Indonesia, China, Iran, Turkey, Poland, Germany, United Kingdom, France, Spain, Argentina, Brazil, and Mexico [15-18]. Besides the cultural aspect, another possible explanation for the inter-country differences in mean total fluid intake is the difference in assessment method used in the countries. In nutrition research, the method of assessment is a key point because people can forget, overestimate, or underestimate their dietary intake,
Adapting an international recommendation to one country might be challenging due to the fact that drinking and eating habits of individuals are specific to each culture. and such actions, consequently, affect the accuracy of the data. The method most widely used for dietary assessment is "24h dietary recall," which requests individuals to remember all food and fluids consumed during the past 24 hours. A second method used to assess dietary intake is a diary or record: individuals record, in real time, over a period of one or more days, what they eat and drink. The data present in the Liq.In database was collected with such a diary covering seven consecutive days. The Liq.In record had an additional special feature: it was specific for fluids. A comparison of data collected with a 24h dietary recall versus those collected with a seven-day fluid record demonstrated that with a 24h dietary recall, individuals significantly underestimate about 400ml of their fluid intake [19]. This potentially implies that, because the reference values
are based on food surveys and many food surveys use a 24h recall in their national surveys, the reference values for water intake are underestimated. Because all surveys providing data to the Liq.In database were performed with the same record, the results of the different countries can be compared. The results of the surveys showed that in the 13 countries, approximately 60% of men drank less than 2 L/day and 40% of women less than 1.6 L/day [17]. However, the proportion of adults with an average fluid intake below the references ranged from 30% in United Kingdom to 71% in Japan, showing again the large difference in drinking habits between the countries [17]. The Liq.In surveys not only assessed the amount of fluids but also the type of fluids consumed. It showed that 25% JAN/FEB 2017
BWR
17