So, yet another diet question here.
I wish to know the difference between these two fat types.
It leads to confusion and error to divide fats into categories in this way. I know that countless authors do it and doctors do it and so forth, but it’s not a helpful practice for understanding at all. Quite the opposite actually.
It is about as good as dividing fats into those whose first letters start with A-J versus K-S or T-Z.
Having the same number of double bonds – which is what distinguishes saturated and unsaturated fats, or saturated vs monounsaturated vs polyunsaturated – does NOT make the fats the same.
Each fatty acid has its own individual properties.
DHA and EPA are very important essential fatty acids, as is GLA.
Oleic acid, richly present in olive oil and in high-oleic safflower oil (but not all safflower oil is high-oleic) is also important but as the body can itself produce it, it is not categorized as “essential.”
Lauric acid, for example, is another useful fatty acid, present in coconut oil.
As for saturated fatty acids such as stearic acid, in the context of a good diet these are perfectly okay. In the context of a poor diet, then reduction of fatty acids such as stearic may show some benefit, but the better thing to do would be to have a good diet in the first place.
In this context, by “poor diet” I mean low protein, high carb, probably high sugar, and poor overall fatty acid profile.
When Google just won’t do:
and of course Wikipedia:
Even reading the Wikipedia page which is far from complete gives an indication that things are not so simple.
As Bill points out the rest of the diet is very important. How good is the data for people eating well 80% or more of the time vs. average?
% of Calories from Food in North America:
Cereals (over 80% of cereal consumption is wheat based, and around 80% or more is refined)
Canada - 24%
USA - 24%
Refined Sugars
Canada - 10.7%
USA - 18.6%
Vegetable Oils
Canada - 19.7%
USA - 17.6%
Totals for nutrient poor calories (taking into account 5% of cereals that are whole grains)
Canada - 50%
USA - 55%
This is the standard diet against which one can assume large population studies are to be compared against. Suddenly altering saturated fat a few percent doesn’t seem like such a big deal compared to replacing half your intake with food, regardless what fat content may be.
I believe that using the classifications of saturated, monounsaturated, and polyunsaturated fat, makes sense as a tool in balancing fat intake from quality food. For example, beef has almost no polyunsaturated fat, adding 10-15g of walnuts and a few fish oil caps will nicely round it out. With fatty fish, no such tweaking is needed. Chicken is low in omega 3 polyunsaturated fat, so flax seed and fish oil will balance the fats.
As for amount of fat intake, currently (ok, 5 years ago - 2004 data) in Canada if one were to simply apply the saturated fat as a percentage of total calories, one would get 9.6%:
average Kcal consumption: 2674
SAT FAT: 28.47g = 256 Kcal
MONO FAT: 52.26g
POLY FAT: 21.15
If we were to simply balance these groups and the o3/o6 ratio, we could try to cut SAT 8g to get to the 7% number and increase POLY, but the 50% crap will not have changed. Even if we get cute and use flax seed and fish oil only to increase POLY so as to balance omega 3 and omega 6 fats as well as adding important long chain fatty acids (DHA/EPA), one is still consuming nutrient poor sources for the most part and likely little will change.
I am thankful to all the great answers. This’ll take a while.