Sue Baumgardt says plant oils offer better protection for health than fish oils (Letters, October 28).

I have been studying omega fatty acids for two years so I assume she is talking about the omega 3 and omega 6 acids.

The highest omega 3 levels in plant oils are found in flax oil - this is called ALA.

However, in order for ALA to be functional in the body, it needs to be converted into EPA and DHA by the delta-6-destaurase enzyme.

It is well established that about 30 per cent of the population is deficient in this enzyme and this makes flax a poor source of the omega 3 fats.

Fish oils contain EPA and DHA in a form which requires no conversion.

It is also important to realise that the omega 6 fatty acids are a double-edged sword.

We need small amounts of omega 6 but excess - in the form of, say, evening primrose oil - can cause many more problems that it solves.

If your readers want to get the facts I suggest they read Fats That Heal: Fats That Kill by Udo Erasmus and The Omega RX Zone by Barry Sears.

-Simon J Boyd, Newhaven