• By focusing primarily on healthy eating and food choices, existing guidance overlooks the undermining effect that poor hydration choices can have – and equally the benefits of good hydration choices such as water.

• The Eatwell plate, for example, could be usefully re-designed replacing soft drinks with water and incorporating reduced carbohydrates and a redefinition of fats.

The European Food Safety Agency (EFSA) recommends a total water intake of 2.0 litres a day for adult women and 2.5 litres a day for adult men under normal conditions. A greater intake is needed for those taking part in intense exercise, those who are pregnant or sick, or when the weather is particularly hot or humid.

While some fluid in the diet will come from food, the majority of this will come from drinks throughout the day. There are two related issues to consider:

(1) The importance of adequate fluid intake to maintain good health. Studies have proven that poor hydration can affect  brain function. The benefits of an adequate fluid intake – particularly water – include maintaining a proper fluid balance within the body, maintaining normal bowel and kidney function, controlling hunger and maintaining an optimum cognitive ability. It is also an essential element of exercise.

• Yet it is not clear that the people of the UK are remaining properly hydrated. The initial findings of the UK Fluid IntakeStudy, published in 2012, found that 30 per cent of adults had inadequate intakes of fluid – as did more than 50 per cent of children. The study also found low levels of water consumption in relation to hot beverages and sugar sweetened beverages.

• These figures are backed by separate studies commissioned by the Department of Health and Food Standards Agency. This body of research has shown that children aged four to ten years typically consume 276ml  of water per day and 620ml from other beverages (of which216ml was milk). Children and young people aged 11 to 18 years were found to consume 453ml of water per day and 680ml of other beverages, of which 150ml was milk.

(2) The contribution of fluid intake to calorie consumption. The initial findings of the UK Fluid Intake Study found that on average, sugar sweetened beverages provided 175 kcal per day of the calorie intake of children. This demonstrates the contribution that sugar sweetened beverages are making to rising levels of obesity.

• A study published by the British Journal of Nutrition in 2012 showed that, in 2008/09, beverages accounted for 21%,14% and 18% of daily energy intake for children aged 1.5–18 months, 4–18 years, and adults (19–64 years) respectively. 

• The study noted that, since the 1990s, there had been an increased consumption of fruit juices (as well as reduced-fat milk) among children, while adults saw similar trends but additionally saw an increased consumption of alcohol. The study highlighted that using water as a substitute for caloric beverages may reduce overall energy intake. 

• From a policy perspective, this leads to an imperative to acknowledge the contribution of sugar sweetened beverages to the diet and take steps to reduce this level. Many people will pay attention to what they eat, while overlooking the fact that sugar sweetened beverages can make a significant contribution to the amount of calories they consumer. In particular, there is a tendency to overlook the contribution that fruit juices and smoothies can make to sugar intake. While such drinks can provide one portion of the daily fruit and vegetable intake, the amount of sugar contained is  similar to many carbonated beverages, the acidity can have a negative impact on dental health, and many of the juices lack the fibre content of fruit and vegetables, lessening the benefits to digestive health. 

• Policy should focus on reducing the amount of sugar in beverages, reducing the amount of sugar sweetened beverages that are consumed, and promoting water or low calorie alternatives as the best way of remaining hydrated. 

• Change4Life acknowledges this need, recommending that “all the family swapping to water, milk (ideally semi-skimmed, one per cent or skimmed), or sugar free drinks  can really make a difference.” However, there is a need to make this more prominent in public health messaging.