A reader write in with the following comments about coconut oil:
"Or coconut oil, that is being sold now as a panacea. Many say that coconut oil actually causes fat loss and is good for your heart and is a superior source of quick energy!!! It has something to do with the fact that coconut oil has medium chain fatty acids as opposed to long chain found in butter etc. I would love to write a letter to McDougal or someone like that and ask about coconut oil and these claims."
This gentleman was exactly right: coconut oil is being touted as a panacea. One of its biggest advocates is Dr. Mercola who just happens to make a killing on every bottle he sells on his web site. Another group that loves coconut oil is the Paleo Diet advocates, because it's high in saturated fat and, therefore, must be a testosterone-boosting, miracle-working superfood, right?
Well, I have a question for those following the current Paleo Diet craze:
Have you ever noticed how almost all Paleo guys are always either 1) under 40 or 2) heavy exercisers? There is a reason for that and it is blood flow (and, therefore, erections).
Many studies have shown that saturated fat slows down blood flow in humans.  One study even did a comparison between a nasty high saturated fat meal and a nasty high glycemic, low fat, high carb meal. Guess what they found? Blood flow was better after the high glycemic, low fat, high carb meal!  Both meals were bad, but the high saturated fat meal did even worse.
Again, the only way to compensate for the negative effects of saturated fat is to 1) either be young or 2) exercise like a wild man.
So then the Mercola question remains: is organic, extra virgin coconut oil somehow an exception?
The answer was clearly shown in the famous "cake and shake" study - which used pristine, organic, virgin coconut oil - where researchers clearly found that flow-mediated dilation decreased by 32% after coconut oil consumption and only 17% after safflower oil (3 hours post-meal).  Once again, researchers found that saturated fat impairs blood flow, but the Paleo crowd just refused to accept it.
Their weird arguments are all over the internet and so you can read those if you want. But all I have to say is this: there is no conspiracy here. Maximum erections require maximum blood flow, so if you want to eat saturated fat, then consider doing the following:
1) Take fish oil or consume fish as research has shown this will partially overcome the negative effects of saturated fat.
2) Exercise frequently (a couple times per day)
3) Consider eating a few walnuts as this also has been shown to partially overcome the blood flow issue of saturated fat. I cover this elsewhere on my site.
Even then, though, I don't really recommend deliberately trying to increase your saturated fat consumption. Animal studies show that coconut oil by itself will push cholesterol (and possibly triglyceride) levels much higher than compared to fish oil.  Dr. Weil gives a very balanced response for those interested.  Please read these links on The Potential Dangers of Saturated Fat and The Potential Dangers of the Atkins/Paleolithic/Low Carb Diet for more information.
Leave the coconut oil and saturated fat for the young guys. After twenty years (unless they are extremely careful), they'll end up with clogged arteries just like the rest of the West and will have to start researching the Ornish Diet to try to clear out all that arterial plaque and improve blood flow for erections.
1) Journal of the American College of Cardiology, Aug 2006, 48(4):715-720, "Consumption of Saturated Fat Impairs the Anti-Inflammatory Properties of High-Density Lipoproteins and Endothelial Function"
2) Arteriosclerosis, Thrombosis, and Vascular Biology, 2005; 25: 1274-1279, "Flow-Mediated Dilatation Is Impaired by a High Saturated Fat Diet but Not by a High-Carbohydrate Diet"
3) Journal of the American College of Cardiology, 2006; 48(4): 715-720, "Consumption of Saturated Fat Impairs the Anti-Inflammatory Properties of High-Density Lipoproteins and Endothelial Function"