Does eating fish really prevent eczema?
Publication Date:26/09/2008
Feeding children fish at an early age could help prevent eczema, a new study tells us. And so could having a pet bird. But how good is the research? We take a closer look.
What do we know already?
Eczema is a medical condition that causes patches of itchy, flaky skin. It's common in children, and in most cases is caused by an allergy. It's linked to other allergic conditions, and tends to run in families along with hay fever and asthma.
Allergies are getting more and more common, so there's been lots of interest in what causes them. One theory is that living in a clean environment means we aren't exposed to dirt and germs when we're growing up. Some doctors think this means our immune systems don't develop fully, which causes allergies.
For example, some research suggests that being around pets as a baby may help to prevent asthma. Pets bring dirt into the home, which might give the child's immune system a boost. It becomes slightly more complicated for older children, because once a child has developed asthma or another allergy, dog or cat fur could trigger their symptoms.
Researchers in Sweden have now done a study looking at around 5,000 children. Parents filled in questionnaires about all aspects of their children's lives. The questionnaires were filled in when their children hit 6 months, and then again at 12 months. The researchers used the questionnaires to look for possible causes of eczema.
What does the new study say?
About 2 in 10 children had symptoms of eczema by the age of 12 months. Children were most likely to get eczema if their parents had it.
There were also some slightly surprising findings. Children who were given fish to eat before reaching 9 months also had a lower risk of eczema. The researchers suggest that a type of fatty acid called omega-3, which is found in fish, could possibly explain this lower risk. But they cannot be certain, because they found no difference in the risk of eczema between children who ate white fish and those who ate oily fish, which is a lot higher in omega-3.
Having a pet bird was linked to a lower risk of eczema, although pet dogs had no effect on risk. The researchers suggest that exposure to feathers may decrease the risk.
Where does the study come from?
The researchers were based at several hospitals and universities throughout Sweden. The study was published in a journal called Archives of Disease in Childhood, which is owned by the BMJ Publishing Group. It was funded by several organisations, including the Swedish Asthma and Allergy Association.
How reliable are the findings?
The first thing to remember is that in this type of study, there may be other factors at work that the researchers didn't take into account.
For example, it could be that parents who suffer from allergies are reluctant to have birds in the house. Their children inherit eczema from their parents, and also grow up without a pet bird for company. This doesn't mean that not having a pet caused their eczema.
Similarly, families who give their children fish to eat from an early age are likely to be different in lots of other ways to families who don't.
Another problem with the study is that researchers looked at lots of different foods, and dozens of aspects of the children's lives. Here are just some of the things they looked at (none of them appeared to be linked to eczema):
- How old the children were when they first had cows' milk and eggs
- Whether they ate butter or margarine
- Whether children ever slept in their outdoor clothes
- Whether the family owned a holiday cottage
- Whether the family moved house early in the child's life
- What position the children slept in.
If you look at dozens of factors, and then pick out the ones that appear important, it increases the chances of getting a fluke result.
What does this mean for me?
It's entirely possible that lifestyle and diet affect whether children get eczema. Unfortunately, there's no proof from this study that giving your child fish to eat from an early age, or keeping a pet bird, can prevent eczema in your children.
What should I do now?
Many parents instinctively feel that anything that may help to reduce their child's risk of an unpleasant medical condition seems to be worth trying. But in this case, bear in mind that the study is quite limited in what it tells us. It doesn’t tell us that feeding your child fish, or keeping a bird, will prevent eczema. There are also other things to consider, like whether other people in the house might be allergic to feathers.
Fish contains plenty of nutrients, and is generally recommended by dieticians as part of a healthy diet. Advice for parents in the UK says that breast milk contains all the nutrients a child needs up to the age of 6 months. The Food Standards Agency, which advises on food safety, says that children can safely eat fish from 6 months onwards.
Bear in mind that the most important risk factor for eczema is family history - something you can do nothing about.
From:
Alm B, Aberg N, Erdes L, et al. Early introduction of fish decreases the risk of eczema in infants. Archives of Disease in Childhood. Published online 25 September 2008.
To read more, see our information on eczema.
News Archive
© BMJ Publishing Group Limited ("BMJ Group") 2007. All rights reserved
This information does not replace medical advice. If you are concerned you might have a medical problem please ask your Boots pharmacy team in your local Boots store, or see your doctor.
