Fat Facts – Part 1

Foods with Fat we should definitely be eating
Foods with Fat we should definitely be eating

“Mummy is Fat good for you?”

Several minutes later bored looking child switches off.  I often give clients and carers at the children centre a run down about fats and reading an article recently on the subject related to cardiovascular disease, I realised how complex it is.  So I decided it would be useful to give some basic fat facts.  So, in this blog I aim to give you the jargon  and what foods contain which fats.  Then, in another blog, I’ll relate some of what we know about the benefits of fats and the possible risks.  I don’t profess to know everything, but I’ll aim to relay some of the accepted thinking and some of the disputed thinking.

The fats we are talking about are the fats present in our food and here we quickly enter the chemistry world; I will attempt to keep it simple, it’s basically all Carbon, Hydrogen and Oxygen atoms! Picture spheres (atoms) with sticks between (bonds).

Fats have building blocks called fatty acids.

The Fatty bit: is a Methyl group CH3 and a chain with lots of CH2’s, this bit is water insoluble (Hydrophobic)

The Acid bit: is a carboxyl group COOH this bit is water soluble (Hydrophilic)

Fatty acids can then be split into 2 groups.

  • Saturated: All the carbons in the chain have 2 hydrogens
  • Unsaturated: Some of the Carbons have lost a hydrogen and therefore have a double bond
Fatty acid structure
Fatty acid structure

Unsaturated fatty acids can be further split into 2 groups:

  • Monounsaturated fatty acids (MUFAs) – just one unsaturated bond
  • Polyunsaturated fatty acids (PUFAs) – many unsaturated bonds

 

omega-3omega6And finally our PUFAs, which are split into many families, but the two well known ones are:

  • Omega 3 fatty acids where the first double bond is at position 3
  • Omega 6 fatty acids where the first double bond is at position 6

 

 

 

Fatty acids are grouped in 3’s to form triglyceride fats (TG’s).  Triglycerides are the main form of fat in the body and 95% of the fats we eat are triglycerides.  A glycerol molecule joins the 3 fatty acids.

eie-triglyceride

Often we refer to foods as containing a particular fat where as in reality they contain predominantly that fat, but will also contain others.  For example in 100g of butter there is 81g fat, 51 g of saturated fats, 21g monounsaturated fats and very small amounts of polyunsaturated fats.

In actual fact there are 500 different fatty acids so this introduction is very simplified.

 

 

 

 

If you look below, in order to further understand which foods have which fat, I have given some examples. The data comes from averaged data and doesn’t necessarily discern between organic/grass fed/corn fed which is believed to make a difference.

Examples of foods with saturated fats:

 In 100g Fat Sat. Fat Mon.Fat Poly Fat Omega 3 Omega 6 Ratio 6:3
Butter 81 51 21 3 0.3 2.7 9
Lard 100 39 45 11 1.0 10.0 10
Coconut Oil 100 87 6 2 0.0 1.8
Beef (10% fat) 10.0 4.1 4.4 0.3 0.0 0.3 8

Good sources of mono-unsaturated fats:

In 100g  Fat Sat. Fat Mon.Fat Poly Fat Omega 3 Omega 6 Ratio 6:3
Olive Oil 100 14 73 11 0.8 9.8 13
Rapeseed Oil 100 7 63 28 9.1 18.6 2
Avocado 15 2.1 9.8 1.8 0.1 1.7 15
Almonds 49 3.7 30.9 12.1 0.0 12.1 2011

Foods with poly unsaturated fats with examples of good and bad omega 3:omega 6 balance.  Our diet has a predominance of omega 6 fats compared with our ancestors so we need to include more omega 3 rich foods shown by a ratio less than 1 the lower the better.

In 100g Fat Sat. Fat Mon.Fat Poly Fat Omega 3 Omega 6 Ratio 6:3
Vegetable Oil 100 9 57 29 0.0 28.9 782
Flax/Linseed Oil 100 9 20 66 53.3 12.7 0.2
Salmon 12 3 4 4 2.3 0.7 0.3
Linseed/Flax seeds 42 4 8 29 22.8 5.9 0.3
Walnut 65 6 9 47 9.1 38.1 4

It is important to say here that you need to consider the types of foods that are good sources of omega 3.   You are more likely to eat 100g of salmon than 100g of seeds or their oil.  The Omega 3 ‘s present in plant sources are short chains and to have the benefits that the long chain fatty acids (found in oily fish) have they need to be converted and this is very inefficient so more need to be eaten.

Variety is what is called for here, however including those foods with omega 3 fats is definitely beneficial and quite hard to over do it. (although not impossible)

So Mummy is fat good for us?  Perhaps now we can break this down into which types of fat are good for us or which types of food containing fats are good for us?