Risk assessment of vitamin A in liver

In the spring of 2005, the Risk Assessment Unit of the Finnish Food Safety Authority, Evira, started a project entitled “Assessment of Vitamin A Risk of Liver for Pregnant Women,” as requested by the Finnish Food Safety Authority. The project examined the exposure of Finnish women to vitamin A via liver foods and took a look at the need for recommendations related to the consumption of liver during pregnancy.

Risks associated with the consumption of liver have been debated for a long time. Consumers, media and health care personnel are interested in whether it is safe to eat liver. The subject has been of interest in the other Nordic countries as well and there is special concern about the safety of sensitive risk groups (pregnant women and small children).

No actual risk assessment has been made of liver and it is an issue that often comes up for discussion. Besides vitamin A, other harmful substances contained in liver have introduced an element of uncertainty into establishing just what recommendations are needed on the consumption of liver.

The goal of the project was to:
1. examine the content of vitamin A in Finnish beef, pork and chicken liver,
2. find out to what extent women of fertile age are exposed to vitamin A via liver and liver foods,
3. evaluate vitamin A risks for pregnant women if there are no recommendations on the consumption of liver, and
4. create varying scenarios and evaluate whether women could eat certain liver products during pregnancy.

Risk assessment was based on liver food consumption data (FINDIET 2002
study, KTL), obtained recipe information and recent results of vitamin A,
cadmium and lead in liver. To estimate intake, a mathematic simulation model
was designed. Intake was estimated as an average daily intake and
for retinoids also as an intake from single liver meal. The simulation model
results were compared with intake recommendations and upper intake limits.

Based on risk assessment, the following conclusions were made
1. Liver consumption may predispose women to retinoid intakes higher
than what is considered safe during pregnancy. However, the risk seems
to pertain mainly to liver foods eaten as a main course (i.e., liver casserole,
liver patties and liver stew). Safety thresholds are not likely to be exceeded
if only liver sausage or pâté is eaten in moderate amounts.
2. The most efficient way to manage the risk is for women to avoid main
course liver foods during pregnancy. The effect of the other scenarios examined
was notably smaller. Exclusion of sow livers from food production
would have only a minor effect on retinoid intakes from liver foods. If effects
similar to a restricted consumption scenario (no main course liver foods)
were tried to achieve by reducing liver retinoid contents, the retinoid content
of livers should be less than 25% of the present level.
3. When considering the total daily vitamin A intake from the nutritional
point of view, liver consumption has a positive effect. In addition to vitamin
A, liver contains also other benefi cial nutritional elements like folic acid and
iron. However, the benefi ts of eating liver can probably be substituted by a
well-balanced diet with plenty of vegetables and a reasonable amount of
meat without the risk of an excess intake of retinoids.
4. Cadmium and lead exposure from liver foods is relatively low when compared
with other dietary sources. The high iron content of liver may reduce absorption of cadmium and lead from liver foods.

Research group

Kirsti Savela (Evira)
Tiina Lavikainen (Evira)
Tero Hirvonen (Evira)
Christina Bäckman (Evira)

Group of experts

Annika Nurttila (Evira)
Kaija Hasunen (Ministry of Social Affairs and Health)
Hillevi Latvalahti (Finnish Food and Drink Industries’ Federation)
Satu Lievonen (Evira)

Joint committee

Susanna Eerola (Evira)
Eija-Riitta Venäläinen (Evira)
Marita Aalto (Ministry of Agriculture and Forestry)
Riitta Stirkkinen (Finfood)

Funding

Evira

Project publications

Report

Lavikainen, T., Karlström, U., Bäckman, C. & Hirvonen, T. (2007). Intake of vitamin A, cadmium and lead via liver foods among Finnish women of fertile age — a quantitative risk assessment. Evira research reports 2/2007, Helsinki 2007.