Usually whenever we hear the "F" word, we instantly run for cover. It is very easy to only concentrate on the calorific value of fats, some nine calories per gram compared to 4.2 calories per gram of carbohydrate (CHO) and protein (Pro). Thus trainers, clients and athletes will tend to steer clear of fat as it is associated with higher levels of body fat and many fatal diseases. Although fat has a role in coronary heart disease and such, it is not necessarily the prime candidate as consuming too much CHO and Pro can also be converted into fats. Although this argument is way beyond the scope of this article, for now I want to discuss the benefits of fats in our diet.
First off, I am primarily talking about the "healthy fats" such as omega 3, 6 and 9, rather than saturated fats or trans fats. These are the fats that have many different roles in the body and can be converted into the various substances and chemicals the body needs.
Some of these chemicals or substances I am referring to are known as hormones or more specifically "steroid hormones." These are derived largely from cholesterol (a lipid or fat), and just how similar they are in molecular structure is demonstrated below:
Hormones can be broken down into two different categories: steroid hormones and polypeptide hormones. A hormone’s role is primarily the same: A hormone is a specific chemical messenger substance made by an endocrine gland and secreted into the blood to regulate and co-ordinate the function of distant organs. The effect of any given hormone is exerted in two different ways. The most important are listed here:
||Derived from cholesterol/fat
||Derived from amino acid pool
||Non lipid soluble
|Diffuse easily into cells
||Do not diffuse through cell membrane
It can be said from this table that steroid hormones exert their effect from "inside" the cell and interact directly with the cell nucleus, while polypeptide hormones interact with the cell wall and rely on sending messengers inside. This can be compared to walking into the boss’s office, kicking the door down, holding him up by the neck and demanding your pay rise rather than knocking on the door to your boss' office and asking if someone could speak to his assistant who will then in turn speak to him at some point in his busy schedule.
This may go some way to explain why insulin and growth hormone (GH) are only anabolic in the presence of other substrates such as CHO or Pro. This also strongly suggests that polypeptide hormones are not as powerful as their brother steroid hormones and need to be released in much larger quantities for a longer period of time to exert the same level of effect.
Testosterone and similar steroid hormones help to burn fat as a fuel source for metabolism as well as directing amino acids into muscle cells, thereby decreasing fat mass while increasing lean tissue mass. This provides great data on why resistance training yields results in body fat measurements as well as in strength gains. Surely then it seems plausible that without adequate levels of correct fats in our diet, hormone production could be slowed due to an inability to synthesize the correct hormone balance?
In one recent study, researchers looked at blood concentrations of free testosterone, testosterone and growth hormone (GH). The joint Finnish/American researchers were interested in which anabolic hormones would be sensitive to dietary intake both at rest and after heavy resistance exercise. What they found was very surprising: During the resting phase of the study, a higher fat intake and lower protein intake was associated with increased levels of anabolic hormones in both sedentary and trained subjects. However, during the active phase of the study, the higher fat intake increased anabolic hormones in the trained subjects only. The results from this study make more of an argument for increasing the healthy fats in our clients' diets further, as they are certainly in their training phase.
This is especially prudent information as current diet and nutrition logic applies plenty of reasons to consume descent quantities of CHO and Pro but not fats. In addition, where good fats are encouraged, it’s very common to find it limited to a coupe of small capsules a day or a portion of fish once or twice a week.
In closing, I would like to add that more research data is needed in regards to fats, hormones and their role in health/performance. However, a very recent study showed that higher dietary fat seems to play a decisive role in the efficiency of growth hormone and in protein conservation. Again, researchers found that this appears to be linked more with trained subjects rather than sedentary counterparts.
When next analyzing your own diet or your client’s food diary, have a closer look at the ratio of Pro, CHO and fat content. It may explain a lot about current progress and advancement in your training program. If you see a lack of healthy fats and plateaus in strength/performance and no body fat reduction, try increasing fish portions or mixed nuts to levels suggested below or encourage supplements every day with breakfast. Whatever your intervention, I advise small steps of change and increasing the healthy fats while decreasing carbohydrates and not protein!
|Ideal Intake (portions per week)
||12-14 (2 per day)
- Norrelund, H. et al: The decisive role of free fatty acids for protein conservation during fasting in humans with and without growth hormone. J Clin Endocrinal Metab 2003;88(9):4371-8.
- Sallinen, J. et al: Relationship between diet and serum anabolic hormone responses to heavy resistance exercise in men. Int J Sports Med 2004 Nov; 25(8):627-33.
- Selye, H. 1978. The Stress of Life – revised ed: McGraw Hill Inc.
- Tortora, G. J. 2002. Principles Of Anatomy And Physiology: John Wiley & Sons.
- Wilmore, J.H. & Costill, D.L. 1994. Physiology of Sport and Exercise: Human Kinetics.