Hundreds of scientists from more than 40 countries are descending on Brighton and Hove for a congress this week, all with an interest in the health effects of dietary fats.

While we're told to eat a low-fat diet, the congress will hear about the important role of oils in health.

Before the advent of processed food, there was no need to know about the nutritional content of our food. Now it's becoming increasingly important to learn exactly what our foods, in particular the fats, are doing to us.

Did you know that human brain tissue contains about 60 per cent fat and that essential fats are crucial for every cell in your body?

A diet rich in the right kind of fats will help maintain a healthy heart and immune system, as well as healthy skin, hair and joints. This is found in fish, nuts, seeds and selected vegetables.

Our modern diet, however, is low in beneficial fats and high in harmful fried and hydrogenated fats.

It's also high in sugar, which interferes with the function of essential fatty acids.

Dr Alex Richardson, a senior researcher at Oxford University, has been investigating the role nutrition plays in diverse mental health conditions, including dyslexia, attention deficit hyperactivity disorder, depression and schizophrenia.

She says the two omega 3-essential fatty acids, DHA and EPA, are woefully lacking in our diet now.

Vegetable oils (sunflower, corn and others) and the processed foods found in supermarkets don't contain omega-3 oils.

The best food sources of DHA and EPA are deep sea, cold water fish such as herring, mackerel and sardines.

DHA forms one of the building blocks of brain tissue but our dietary intake has substantially reduced over the past 50 years. Low levels are associated with memory loss, visual problems and neurological conditions.

Studies show a severe deficiency in DHA may lead to a greater incidence of premature birth and behavioural or learning problems. Eating four or five servings of cooked, fatty fish weekly satisfies DHA requirements.

However, much fish and commercial marine oil is polluted with mercury and other contaminants so supplements may be wise.

While DHA is important for brain structure during early development, EPA is crucial for the moment-by-moment regulation of brain function.

Dr Richardson's aim is to provide access to reliable scientific information. She has set up a charity called Food and Behaviour (FAB) Research.

For more details, visit www.fabresearch.org or write to FAB Research, PO Box 6066, Nairn, Scotland IV12 4YN.

Martina is a qualified nutritional therapist and works at the Crescent Clinic of Complementary Medicine and the Dolphin House Clinic. Call 01273 324790 or visit www.thehealthbank.co.uk
If you have a question for Martina, write to her at Features Department, The Argus, Argus House, Crowhurst Road, Brighton BN1 8AR or email features@theargus.co.uk