px-r-F5cPQX9ZxUrwgORsMGDGwU Kuhnesiology: Article # 4 on Justflysports.com

Thursday, March 15, 2012

Article # 4 on Justflysports.com

On a low-fat diet?  Might want to read this...and reconsider.


Nutrition for the Power Athlete:  Part 4.  Fat

To conclude the explanation of the macronutrients, we must address fat.  Generally speaking, Power Athletes and the general public should have similar fat intake percentages, which comes to about 30% of total caloric intake. This is because fat, but not just any kind of fat, is very necessary for promoting optimal health. When you break it down...if you aren't healthy, how can you train or compete?

The idea that fat = bad is still very prominent in today's society. This notion is pretty unfortunate since fat (fatty acids) plays such an important role in so, many aspects of human physiology, like providing energy, aiding in the transport of the "fat-soluble" vitamins A, D, E, and K, and promoting anabolic hormone production to name just a few. So how much do you need?

The general consensus is that about 30% of your total caloric intake should come from fat, with 10% or fewer of total caloric intake coming from saturated
fats (keeping as far away as possible from trans fats). The very interesting and important thing to understand is that 1 gram of fat contains 9 calories. That's more than double the calories per gram of protein and carbohydrate. The International Society of Sports Nutrition recommends 10-15% of your total caloric intake come from monounsaturated fatty acids, and 10-15% of total caloric intake come from polyunsaturated fatty acids, with some saturated fat as well. This recommendation is due to the overwhelming evidence from research that is showing a higher fat diet helps to maintain circulating concentrations of anabolic hormones such as testosterone.  There exists much evidence (The Malmo Diet and Cancer Study) that high fat diets, even ones with greater than 10% saturated fat, are not detrimental to health and do not increase mortality.

What's the difference between saturated and unsaturated fatty acids? Glad you asked. It all comes down to molecular bonds and the number of hydrogen atoms that the fat molecule contains. Saturated fat has no carbon-to-carbon double bonds and is "maxed-out" by hydrogen bonds. Because of their molecular nature, they have a higher predisposition to being stored as opposed to used as fuel in comparison to unsaturated fatty acids. In general, saturated fatty acids are solid at room temperature while unsaturated fatty acids are typically liquid (oils) at room temperature.

Saturated fats are mostly from animal sources as well as oils that have been hydrogenated (like margarine), while unsaturated fats are mostly from plant sources. There are two kinds of unsaturated fatty acids:  Monounsaturated fatty acids contain one carbon-to-carbon double bond, and Polyunsaturated fatty acids that contain two or more carbon-to-carbon double bonds. In a similar fashion to specific amino acids characterized as "essential," some Polyunsaturated fatty acids must be obtained from the diet from either plant or animal sources since they cannot be synthesized. Due to our inability to create specific carbon-to-carbon double bonds at specific positions on fatty acid molecules, we must get the unsaturated fatty acids Omega-3 (linolenic acid) and Omega-6 (linoleic acid) from our diet. Though we need both Omega-3 and Omega-6 fatty acids, the specific ratio of these is very important since Omega-6 fatty acids are known to be "proinflammitory" and can therefore play a role in negatively affecting recovery and health if too much is present in the diet. This is an issue since the typical "western" diet has a ratio of about 20:1 of Omega-6 to Omega-3

The Institute of Medicine suggest a 7:1 ratio of these fatty acids. Research just published in the journal Prostaglandins and Other Lipid Mediators, and conducted by Weylandt, et. al.  has shown that Omega-3, on the other hand, reduces inflammation via the production of lipid mediators protectin and resolvin.  Buckley and Howe explain in their review of Omega-3 fatty acids that the role of these lipids may even be beneficial in preventing obesity. The review also states that Omega-3 fatty acids do more than help prevent obesity: "...including suppression of appetite, improvements in circulation which might facilitate
nutrient delivery to skeletal muscle and changes in gene expression which shift metabolism toward increased accretion of lean tissue, enhanced fat oxidation
and energy expenditure and reduced fat deposition."

Wait a minute. Eating Omega-3 fatty acids does what?

-Improves circulation and nutrient delivery
-Shifts metabolism toward lean tissue growth
-Increases the amount of stored fat that is used as energy

Do those sound like beneficial things when it comes to training? Yeah. Those are good.

So what are some good sources of these mono- and polyunsaturated fatty acids?

Monounsaturated:  Olive oil, canola oil, and peanut oil, as well as avocados and most nuts.

Polyunsaturated:  Corn oil, flower oils, sesame oil, soy oil, as well as most nuts and seeds.

What about good sources of Omega-3 fatty acids?

Walnuts and most cold water fish, such as herring, tuna, sardines, mackerel, and salmon. Also...it is pretty easy to find fish oil supplements.

And...since Power Athletes can eat some saturated fat, good sources include: beef and poultry, as well as dairy products. For non-animal source saturated fat, sources include: coconut oil, palm oil, and kernel oil.

AVOID trans fats, which have been shown to promote obesity and other inflammatory diseases, such as heart disease, certain cancers, and diabetes. Trans fats, which are usually plant oils that have been processed to extend shelf life or "hydrogenated" to obtain a specific "solid" characteristic have also been shown to: increase "bad" LDL cholesterol
decrease "good" HDL cholesterol
increase C-reactive protein (a marker of muscle damage and breakdown) 

To avoid these trans fats, check the ingredients label.  If it says "trans fat," "hydrogenated," or "partially-hydrogenated," it should be limited or avoided.

(Note: Just because a label says 0g of trans-fat, this doesn't mean it doesn't have any trans-fat. Food companies can put 0g of trans-fat on their label if there is less than .5g in a serving, so check the ingredients list for the "hydrogenated" or "partially hydrogenated" key words!)

If you can consume the good fats and limit the bad ones, it will really help you as an athlete!  So don't be afraid of fat.  It does much more than insulate and keep you warm.


Buckley, J.D. & Howe, P.R.  (2010).  Long-chain Omega-3 Polyunsaturated Fatty Acids may be Beneficial for Reducing Obesity - a Review. Nutrients.  2(12):  1212-1230.

Hofheins, J.  (2008).  An Overview of Macronutrients.  In J. Antonio, D. Kalman, J.R. Stout, M. Greenwood, D.S. Willoughby, and G.G. Haff (Eds.), Essentials of Sports Nutrition and Supplements (pp. 349-370).  Totowa, New Jersey:  Humana Press

Leosdottir, M., Nilsson, P.M., Nilsson, J.A., Mansson, H., & Berglund, G.  (2005). Dietary Fat Intake and Early Mortality Patterns - Data from the Malmo Diet and Cancer Study. Journal of International Medicine.  258:  153-165. 

Lowery, L.  (2008).  Fat.  In J. Antonio, D. Kalman, J.R. Stout, M. Greenwood, D.S. Willoughby, and G.G. Haff (Eds.), Essentials of Sports Nutrition and Supplements (pp. 349-370).  Totowa, New Jersey:  Humana Press

Stoppani, J., Scheett, T.P., & McGuigan M.R.  (2008). Nutritional Needs of the Strength/Power Athletes. In J. Antonio, D. Kalman, J.R. Stout, M. Greenwood, D.S. Willoughby, and G.G. Haff (Eds.), Essentials of Sports Nutrition and Supplements (pp. 349-370).  Totowa, New Jersey:  Humana Press

Weylandt, K.H., Chiu, C.Y., Gomolka, B., Waechter, S.F., & Wiedenmann, B.  (2012). Omega-3 Fatty Acids and their Lipid Mediators:  Towards an Understanding of Resolvin and Protectin Formation.  Prostaglandins and Other Lipid Mediators.  (Epub ahead of print).  

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