I wanted to find out some more about saturated fat's effect on testosterone, so I did a bit of research. The most detailed article I could find in my quick search was actually from another fitness-themed website.
Again, I'm not very familiar with how this works, but it seems like the scientists aren't unsure as well. I'm not necessarily contesting the idea-just am keeping an open mind about it. I just thought I'd highlight some important points from what I read:
-"...most studies compared vegetarian-type diets to western-type diets. This presents several problems when trying to explain the hormonal responses from the dietary manipulations. The first is that other dietary factors were altered in addition to fat intake. These included fiber content and the presence of various phytonutrients like flavonoids, isothiocyanates, etc. The main point is that there are many factors that can determine the effects of dietary fat on T levels. Most studies did not even report the amounts of fatty acids in the subjects? diets, let alone the content of phytonutrients, so these factors were most likely not controlled for. Furthermore, differences in the length of the treatments (2 weeks vs. 10 weeks), lifestyles of the subjects (active vs. sedentary), and calorie loads (2800 vs. 4374) are additional examples of factors that can impact the results."
-"Another important finding was that urinary excretion of T was much greater on the high-fat, low-fiber diet (6). Other studies have shown that on higher fat diets, urinary excretion of T is increased (10, 11) while vegetarian type diets may decrease the urinary excretion of T (9, 10, 11). This is an important point to consider in evaluating the level of T bioactivity in the body. If blood levels of T elevate and the excretion rate of T also elevates there may not be a net bioactive effect of T. However, if blood levels of T remain the same and T excretion decreases, that may signal a net bioactive effect of T in the body. While it is difficult to say if a higher fat or lower fat diet would be better for increasing the bioactivity of T, it does appear that higher fat and lower fiber-type diets are associated with greater excretion of T. "
-"The results do not support one another and only point to the fact that dietary fat plays a role in modifying T production, but that role is still unclear."
-"Remember, it is the bioactive fraction of total T that is important. This fraction consists of fT and albumin-bound T. Fasting suppresses T production and small amounts of either PRO or CHO do not reverse the suppression. Diets with a PRO intake greater than the CHO intake lower total T levels, and may actually decrease the bioactivity of T in the body. Higher CHO diets (70% or more from CHOs) may increase T levels, but they also affect the metabolism of T as well. While the role of fat is not entirely clear, saturated fat and cholesterol are closely linked to higher levels of T and PUFAs have some modifying role."
-"It would seem that CHO intake must exceed PRO intake by at least 40% to keep the bioactive fraction of T high. Fat intake should be at least 30%, saturated fat needs to be higher than PUFA, and fiber intake needs to be low. "
In essence, it seems like the correlation between testosterone and saturated fat isn't quite as simple as most of us believe.