Dietary assessment

Dietary guidelines give us recommendations for a healthy diet, but how does this measure up to what we are actually eating?

Assessment of dietary intake is one of the first steps to establish what a person is actually eating.

The assessment helps to identify quantitative and qualitative characteristics of our diet and, if need be, support changes.

Dietary assessment methods

Dietary assessment methods are broadly grouped as indirect and direct methods:

1. Indirect methods – use secondary data such as population-based statistics on food supply, availability, and consumption (eg food balance sheets or household surveys)
2. Direct methods – either retrospective or prospective, use individual-based information to assess the food intake on a personal level (eg dietary history, screens).

On the personal level, assessing dietary intake can help understand eating habits, track down eating patterns and map out areas for improvement. There are a few simple tools that could help record, estimate and monitor food intake.

The most popular assessment tools in practice and research are:

• Diet Record:
  Recording all food and beverages consumed over 3 days (commonly 2 weekdays and 1 weekend)
• 24-Hour Dietary Recall:
  Reporting all food and beverages consumed over last 24 hours in an interview
• Food Frequency Questionnaire:
  Reporting frequency of consumption and portion sizes of a range of foods and beverages over a long-term period (commonly over 1 year).

There are other simple tools that could help assess dietary intake on a personal level, such as food diaries and checklists.

Using a food diary

A food diary or food journaling should include:

• When and how?
  What time you are eating or drinking and in what setting (eg lunchtime sandwich at home, apple in the car on the way to work, or dinner with friends)
• What?
  Type of foods and beverages consumed and how these were prepared (eg baked mixed vegetables or fresh fruit salad)
• How much?
  Quantity of the consumed foods or beverages, either weighed or estimated using household measures (eg 1 cup of yoghurt or 2 tablespoons of almond butter on a thin slice of a wholemeal bread)

It’s helpful to write down foods and beverages as soon as you consumed these and to be as specific as possible. A food diary could be used to estimate the overall intake of food, assess diet quality, identify areas for improvement (eg eating on the run or unhealthy snacking), monitor impact of diet on psychological and physiological state (eg mood or gastrointestinal symptoms), and plan food budget, shopping and cooking.

Commonly, food diaries are completed for 3 to 7 days to provide a good representation of a person’s average intake. Once completed, food diaries could be analysed against simple checklists. For example, consumption of vegetables, fruit, wholegrains and other food groups.

Using a checklist

Dietary checklists could be used as a part of comprehensive dietary intake assessment or as a stand-alone measure to, for example, calculate a specific score for consumption of a specific food or food group (eg vegetables or take-away consumption checklist).

Dietary checklists are less reliant on memory and may be advantageous to monitor quantitative changes in dietary intake.

Your task

Explore the provided resources in the ‘Downloads’ and ‘See Also’ sections below on the assessment of dietary intake.

Have you tried any of these assessment tools in the past? Or do you think any of these might be useful to you?

Discuss your perspectives with other learners in the comments.