There are many misconceptions on fat and I would like to talk about one of the leading lights in the 'fat debate', and that is Udo Erasmus.

Basically, this man has dedicated his life to understanding the effects of fat and oils on the health of humans. You can follow his work in the many books he has written on the subject.

One of the main issues he tries to put across is that some fats are essential for human health. When he says essential he means that the body can't make it for itself, and therefore it is needed from the diet.

Starving oneself of these fats can cause deficiency and, in the worst case scenario, even death. The two main oils or fats are omega 3 and omega 6; he confirms that these two are the true essential fatty acids.

Erasmus confirms that virtually every seed and nut available contains omega 6, but the point to remember is that salted, roasted and damaged nuts do not fall into this category. It is interesting to note that he confirms that if you are a regular consumer of nuts and seeds you will be unlikely to fall into the omega 6 deficiency category.

I would think that was good news! Most people like nuts; seeds are not so popular, but increasingly they are being added to foods in general. The good news about eating nuts and seeds is that if you are a vegetarian or non-fish eater, they can go some way to provide the essential oils required by your body that fish would supply.

In addition, Udo comments that in some areas of the world, fish is contaminated by mercury, or even toxins, so by ingesting nuts and seeds it avoids possible toxination, while at the same time absorbing the required oils.

The essential oil omega 3 can be gained from plant sources. Udo believes that flax seed is the richest source, while beans and lentils and green vegetables are all contributory.

He makes the point that Hindus do not eat fish or fish oils, but they have as much DHA (an omega 3 derivative) in their brain, eyes and sperm as a person consuming a good Western diet, including fish.

He adds that if they didn't they would be dumb, blind and sterile. Take note those who are making babies! The Hindus get most of their omega 3 from the beans and lentils they use in their food.

The absorption of the omegas is much more complicated than I have room to describe here; however, it is worth defining the specific oils to ensure they are not avoided when trying to lose weight at this time of year. It can only lead to damage in the long term.

Many people would say that eating the essential fats in volume would cause weight gain and this is the issue that needs to be understood. Udo explains that omega 3 fats actually turn on the fat-burning process and turn off fat production, so they can help you lose weight.

He adds it is impossible to gain weight with omega 3 and very hard with omega 6. Most of the weight gain that people blame on fats is caused by eating more carbohydrates than they can burn. In addition it is important to identify the bad fats that should be avoided.

Hydrogenated fats, margarine, vegetable shortenings and partially hydrogenated vegetable oils are all bad fats. These increase the risk of heart attacks, strokes, embolisms and diabetes. He adds that recent research has shown that these fats interfere with liver detoxification, and learning and vision in children. In addition, there is evidence they also interfere with the immune function and reproduction in both male and female animals.

Secondly, avoiding the cooking oils that have been treated with sodium hydroxide and phosphoric acid, then bleached and heating to frying temperature before being bottled. One has to ask how will we know which to choose?

Udo explains that all oils in the supermarket have been treated this way with the exception of extra virgin olive oil. The final avoidance should be of any oils or fats that have been overheated or burned; they turn into a bad fat in this state.

A subject of discussion is how to use oil to cook with. The advice from Udo is that extra virgin olive oil should be added to food and salads after they have been cooked or heated. He believes that the idea of using oil for frying is just another way of selling more oil.

He worked for a company many years ago, who employed a laboratory to measure the stability of extra virgin olive oil when it was heated. They were amazed to find out how quickly the heat damages the oil. So how can we sauté food?

Udo believes that water should be used to do this as it will not burn the food. However, if one insists on using an oil to cook with, then the suggestion is that the least damage occurs with butter and unrefined coconut oil.

This man is a mine of information about fats and oils. I have only been able to touch on his advice here. However, he has a Website www.udoerasmus.com where his various books can be seen too. At least if you do nothing else consider the way good fats should be used and not avoided to keep you healthy for 2007.

Ms Borg is a member of the Guild of Health Writers in the UK, an association of journalists dedicated to providing accurate, broad-based information about health and related subjects to the public. E-mail: kathryn@maltanet.net.