Fish and shellfish

Last updated on 8-8-2025 by Elise Grimm

Why do we study the consumption of fish and shellfish according to guidelines?

A balanced diet plays an important role in maintaining and promoting health. The Superior Health Council provides food-based dietary guidelines tailored to the Belgian population, aiming to reduce illness, premature death, and the overall disease burden caused in part by unhealthy eating habits.
Fish and shellfish are a valuable source of essential nutrients, such as high-quality protein, long-chain omega-3 polyunsaturated fatty acids (such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)), iodine, selenium, zinc, vitamin D and vitamin B12. Nutrient content can vary according to species, diet, environment, maturity and by the way they are preserved and prepared. Regular consumption of fish has been associated with a reduced risk of cardiovascular disease, certain cancers, cognitive decline, and metabolic syndrome, while reducing overall mortality, although there are potential risks associated with high consumption of salted fish and contamination by heavy metals. However, the benefits of eating fish outweigh the potential risks.
The Superior Health Council recommends that adults eat at least 200 g of fish and shellfish per week, including once a week fatty fish (which provide up to 10 times more EPA and DHA than lean fish).

How do we study the consumption of fish and shellfish?

Trained interviewers conducted two non-consecutive 24-hour dietary recalls to record all the foods and drinks participants had consumed on the previous day. These recalls were carried out in a standardised manner using a specialised computer program (GloboDiet®).
Fish and shellfish intake was assessed as habitual intake (also known as usual or long-term intake), representing the average daily intake over the long term. This method accounts for natural day-to-day variations in what and how much people eat, offering a more accurate picture of typical dietary habits over time. This is particularly important when evaluating whether a population meets dietary recommendations. All intakes mentioned in the results below refer to the mean habitual intake, unless stated otherwise.
The statistical tool Statistical Program to Assess habitual Dietary Exposure (SPADE) was used to estimate habitual intake distributions based on the short-term data collected through the 24-hour dietary recalls.
In addition to the 24-hour recalls, the respondents (or parents in the case of children) completed a Food Frequency Questionnaire: they were asked to indicate how often they consumed a specific food or food group in the last 12 months. The response options were: Never, less than 1 time per month, 1-3 times per month, 1 time per week, 2-4 times per week, 5-6 times per week, 1 time per day, 2-3 times per day, more than 3 times per day. Based on this, the proportion of the population that never eats fish and shellfish was assessed.
In this page, we present the habitual intake of fish and shellfish in the population based on statistical modelling, as well as the mean ratio between the amount of fatty fish consumed and the total amount of fish and shellfish (expressed as a percentage). This ratio was calculated, without modelling, for each recall day and then averaged over both recall days for each participant having consumed fish or shellfish. The mean was then calculated and presented for the total population and by subgroups (sex and age, education, region, year).
The detailed methodology can be found here.

What did we include as “fish and shellfish”?

Based on the recommendation of the Superior Health Council, “fish and shellfish”:
- include fresh, frozen, smoked and canned fish (natural or in oil/vinegar), as well as seafood;
- do not include deep-fried fish and fish products such as fish fingers or fish burgers.

The proportion of the population never eating fish and shellfish was calculated based on the following Food Frequency Questionnaire items:
- Fresh or frozen fish;
- Smoked fish (smoked salmon, halibut, mackerel, trout, etc.);
- Shellfish (mussels, oysters, lobster, crab, prawns, etc.).

KEY RESULTS

The population aged 3 years and older in Belgium eats on average 18 g of fish and shellfish per day, or 126 g per week

23% of the adults eat at least 200 g of fish and shellfish per week

Children (3-9 years) and adolescents (10-17 years) eat less fish and shellfish than adults aged 18 years and above

38% of the total fish and shellfish intake of the population aged 3 years and older is coming from fatty fish

People with a low level of education are more likely to never eat fish and shellfish