Food and Nutrition Evaluation and Decision Making
What you must know
This domain requires you to weigh evidence and make justified food choices. You should understand dietary reference values (estimated average requirement, reference nutrient intake, lower reference nutrient intake), the traffic-light and percentage front-of-pack labelling schemes, and how to compare products fairly per 100 g rather than per serving. Know the main public-health dietary guidelines - eat at least five portions of fruit and vegetables daily, choose wholegrain, limit free sugars, salt and saturated fat - and the reasons behind them. You must also evaluate factors influencing food choice: cost, culture, religion, allergies and intolerances, availability, convenience, media influence and health status.
Traps to watch
A frequent trap is comparing foods per serving when serving sizes differ - always standardise to 100 g. Watch for 'low fat' products that are high in sugar or salt, and for health claims that are marketing rather than regulated nutrition claims. Distinguish allergy (immune, can be severe) from intolerance (digestive, dose-related). Beware of questions that assume the healthiest choice is always the most expensive or that guidelines apply identically to every individual.
Worked example
Product A: 12 g sugar per 30 g serving. Product B: 18 g sugar per 60 g serving. Per 100 g, A = 40 g and B = 30 g, so B is lower in sugar despite the larger serving figure. Rule of thumb: convert to per 100 g, then check fat, salt and fibre together - no single nutrient decides whether a food is a healthy choice.