A key part of the Overcoming MS diet suggestions is understanding what fats and oils are, their properties, and how the different types of fats, both naturally occurring and human-made fats, play a role in MS development and progression.
- A fat’s melting point determines how sticky and flexible it will be when incorporated into the fatty membranes of your cells.
- Fats with melting points higher than body temperature (98F or 37C) are effectively solid in the membranes of body cells, making them hard and inflexible.
- Sticky, inflexible cells lead to clots, hardened arteries, and hypertension. They also cause degeneration, which is one key to the development and progression of MS.
Watch this short video to hear from Professor Jelinek about the importance of reducing saturated fat consumption.
Types of fats
A fatty acid is a long chain of carbon and hydrogen atoms, containing a carboxylic acid group.
- Lipids - general term for fatty acids.
- Oil - normally refers to lipids that are liquid at room temperature.
- Fat - specifically refers to lipids that are solid at room temperature, however we will be using 'fat' as a synonym for lipids.
Saturated fats are found principally in animal products, but also in coconut and palm oils.
The term saturated means that all of the carbon atoms in the long chains of these fats, often described as the carbon backbone, are connected to each other with single bonds (and there are no double bonds present). When the carbon chains of these fats have all the hydrogen atoms they can hold, they are said to be saturated with hydrogen.
These fats have high melting points and so are typically solid or nearly solid at room temperature (except for coconut and palm oils). This is critical to understanding the saturated fat-MS connection.
If one double bond is present between any two carbon atoms in a fat, that fat is monounsaturated. A typical example is oleic acid in olive oil.
These fats have lower melting points and so are liquid at room temperature, but will solidify a little or go cloudy in the fridge.
Monounsaturated fats are sometimes called omega-9 fats because the only double bond present in the backbone is at the ninth carbon from the omega end.
If more than one double bond is present, the fat is polyunsaturated.
This is the most reactive kind (as double bonds are reactive and having more of them makes the molecule more reactive) with the lowest melting points and are liquid at room temperature and in the fridge. This means they are more unstable and need to be treated.
Fatty acids are the building blocks of fats. The body breaks fat into fatty acids so they can be absorbed.
Many of these polyunsaturated fatty acids are what we call essential fatty acids. That is, they are essential for normal bodily function, but cannot be manufactured in the body. They must be consumed through diet, and can be thought of in the same way as vitamins.
There are two essential fatty acids in human nutrition. They are named due to the placement of the double bond closest to the start of the molecule.
- Those with the first double bond at the third carbon from the omega end of the chain, known as omega-3 or n-3 fatty acids, are typified by fish oil and flaxseed oil
- Those with the first double bond at the sixth carbon from the omega end, that is, omega-6 or n-6 fatty acids, are typified by all the familiar cooking oils, namely sunflower oil, safflower oil, corn oil, and so on.
What about the other types of fat I've heard of?
Hydrogenated fats / trans fats
Hydrogenation is an industrial process which involves partial hydrogenation (adding hydrogens to double bonds) which solidifies and partially hardens vegetable oil, creating a 'trans' shape. This is often used in the production of cakes and pie crusts.
Trans fats can also be created by heating vegetable oil at very high temperatures (e.g. in a deep fat fryer) which changes the shape of the molecule.