In this section:
Saturated fatty acids
Monounsaturated fatty acids
Polyunsaturated fatty acids
8 reasons we like Omega 3 polyunsaturated fats
More information on Omega 3 Polyunsaturated Fats
More information on Omega 6 polyunsaturated fats
The chemistry / technical part
- Saturated fats are most often animal fats which are often solid or hard at room or refrigerator temperatures. They have high melting points.
- Sources of saturated fats: Meat, milk, cheese, yoghurt, cream and some vegetable products especially coconut oil, coconut milk and palm oil.
- Monounsaturated fats have lower melting points and are liquid at room temperature. They may solidify or go cloudy in the refrigerator. These are found mainly in vegetable oils and nuts.
- Sources of monounsaturated fats: Olive oil and avocado.
- Polyunsaturated fats contain essential fatty acids which you need from your diet as your body cannot make them.
- Polyunsaturated fats have the lowest melting points.
- They are further divided into Omega 6 and Omega 3 polyunsaturated fats.
- Sources of Omega 6: Sunflower, safflower, corn and soybean oils, grape seed, nuts and seeds.
- Sources of Omega 3: Fish oil, flaxseed oil, walnuts, green vegetables.
Foods can have a combination of saturated and unsaturated fats in them. Where they are listed as good sources of a particular fat it generally means the majority of the fat they contain is of that particular type.
- Some studies show Omega 3s are associated with improved quality of life, reduced disease activity and disability for people with multiple sclerosis  
- They may reduce the frequency of relapses for people with multiple sclerosis.
- They lower cholesterol
- They make your blood less sticky which helps to prevent certain strokes and cardio vascular problems
- They are anti-inflammatory 
- They appear to modulate immunity
- They reduce the chance of getting diabetes 
- They reduce the risk of certain cancers  
The three most nutritionally important omega-3 fatty acids are alpha-linolenic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
Alpha-linolenic acid (ALA)
Eicosapentaenoic acid (EPA)
- ALA is also the primary building block for EPA and DHA (see below). Our immune, inflammatory, cardiovascular, and nervous systems need sufficient amounts of EPA and DHA. ALA is also used directly for energy production.
- Good sources of ALA include flaxseed, sardines, salmon, cauliflower, Brussels sprouts, spinach, kale, green beans, romaine lettuce, fish, legumes and strawberries and, raspberries.
Docosahexaenoic acid (DHA)
- EPA produces anti-inflammatory messenger molecules. We cannot produce EPA ourselves so we need to eat food sources rich in EPA, such as fish.
Fish - farmed or wild?
- DHA is particularly important to brain function, and DHA is found in our brains in significant quantities. We cannot produce DHA ourselves so we need to eat food sources rich in DHA, such as fish, especially tuna oil.
Fish have an omega-3 content that is highly dependent on their diet. If they eat algae, sea plants and other foods rich in omega-3s, they are able to store more omega-3s in their tissue. Some farmed fish are fed processed omega-3 concentrates to boost their omega-3 content, other farmed fish are fed few omega-3s and have lower-than average omega-3 content.
A note on canola oil
Canola oil is a combination of saturated, mono and polyunsaturated fats. It is made with a highly unnatural processing method that involves high heat, deodorisation and the toxic solvent hexane. Significant amounts of trans fats are formed during this process.
- The main omega-6 essential fatty acid is linoleic acid. This is found in the oils of seeds and nuts, such as sunflower, safflower, soya, corn seeds, grape seeds, nuts and seeds.
Trans fats are made when liquid vegetable oils are "hardened" or "hydrogenated" to make them more stable and less prone to becoming rancid. This increases the shelf life of a product. Trans fats or hydrogenated fats are found in margarines, cooking oils for frying, shortening for commercial baking.
Trans fats interfere with Essential Fatty Acid absorption in your body and contribute to cardiovascular disease and diabetes. Active measures are being taken by the government to reduce / eliminate trans fats from our foods.
Polyunsaturated oils, including the omega-3 fats, are extremely susceptible to damage from heat, light, and oxygen. When exposed to these elements for too long, the fatty acids in the oil become oxidised, a scientific term that simply means that the oil becomes rancid. Rancidity alters the flavour and smell of the oil and it also reduces the nutritional value.
Look after your polyunsaturated oils in the following ways:
1. Buy cold pressed versions as high temperatures cause rancidity
2. Store in the fridge
3. Do not heat or keep heat as low as possible. If you choose to cook with olive oil do not heat to the smoking point.
4. Keep out of sunlight
5. Store in dark glass or dark containers the sun cannot penetrate
6. Store in airtight containers
- Fats are made up of the molecules carbon, hydrogen and oxygen. All fats have a carbon "back bone" and each carbon atom is linked to each other by a bond
- Saturated fats: If all the carbon atoms in the backbone are connected to each other with single bonds = saturated fat.
- Monounsaturated fats: If there is one double bond present between any of the carbon atoms = monounsaturated fat.
- Polyunsaturated fats: If there is more than one double bond present between any of the carbon atoms = polyunsaturated fat.
- Polyunsaturated fats are further divided into Omega 3 and Omega 6 poly unsaturated fats.
- Omega 3 polyunsaturated fats/ Omega 3 fats: These have their first double bond at the third carbon from one end of the carbon backbone.
- Omega 6 polyunsaturated fats: These have their first double bond at the sixth carbon from one end of the carbon backbone.
Always check with your Dr before changing your diet or supplementing.
Individuals who have disorders involving bleeding, who bruise very easily, who are planning on having surgery or who are taking blood thinners must consult with a medical practitioner before taking supplemental omega-3 fatty acids.
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