Breakfast: Shaping Guidelines from Food and Nutrient Patterns
Michael Gibney and Irina Uzhova
The value of regular breakfast intake for nutrition, health, and wellbeing is widely recognized. Data exist, with varying degrees of confirmation, that a regular breakfast intake may help in body weight management, in cognitive function, and in cardiometabolic health. Regular breakfast consumers also enjoy a more optimal total daily intake of nutrients compared to breakfast skippers. A critically important question that must be addressed by policy makers is the approach to defining an optimal breakfast. Such a definition would involve the enumeration of quantitative nutrient guidelines which should transcend geographic patterns and ensuing food-based dietary guidelines that would reflect local foods and gastronomic customs.
Most governments that have issued standards for optimal breakfasts have done so in the context of food groups such as cereals, breads, fruits, and fruit juices, dairy produce, and pulses. None have based their recommendations on any underlying objective evidence derived from any analysis of existing breakfast patterns. Two countries, the USA and Mexico, have issued statutory guidelines on nutrient and food choices for optimal breakfasts in schools. In both cases, the nutrient recommendations are simply energy-adjusted targets based on prevailing dietary guidelines for adults. Moreover, neither enumerates specific targets for micronutrients and neither do they elaborate on the evidence base for the targets set for food intakes to achieve these nutritional guidelines. In the UK, a voluntary nutrient standard for school meals recommends a universal figure of 20% of daily intake based on the frequently observed finding that breakfast supplies about 20% of daily energy intake. The reality is that the intakes of many desirable nutrients, the minerals and vitamins in particular, contribute far more than 20% to total daily intake.
Cluster and principal component analyses have been used to identify patterns of breakfast food intake. These studies have frequently allowed the intakes of nutrients of different breakfast food clusters to be described in terms of their contribution to both breakfast nutrients and to overall daily nutrients. What is clear from an analysis of some of these data is that intake of nutrients across clusters of breakfast foods is very large compared to the variation that exists for the same clusters as regards total daily intake. In simple terms, good breakfast patterns do not automatically lead to optimal daily nutritional patterns. Equally, poor quality of breakfast nutrients does not determine a poor overall daily nutritional pattern.
One approach which is currently being examined by the International Breakfast Research Initiative is to assign each individual in a national survey with a value for their nutrient-rich food (NRF) index. The NRF index measures dietary quality for both macro- and micronutrients and has been extensively used across the globe to provide a quantitative score of overall dietary quality. For each of 6 national surveys (Canada, Denmark, France, Spain, UK, and USA), tertiles of NRF scores are created, indicating increasing overall energy-adjusted dietary quality. The intake of foods and nutrients for each individual at breakfast is computed for each of the 3 NRF tertiles. This approach is to be explored to establish if optimal breakfast nutrient targets can be defined. As regards food-based dietary guidelines, these will alter across different gastronomic traditions, but some critically important points need to be noted before food advice for breakfasts is issued. The average population intake of a food is a function of 2 elements: the percentage of the population consuming the food and the mean intake of the food among consumers of that food. The average intake of yogurt across NRF tertiles is constant for yogurt consumers. However, as NRF scores improve, more people eat yogurt. This approach is essential for public health nutrition in improving breakfast food choice toward achieving an optimal nutrient intake.