Do cholesterol levels matter? As you may know, that is a highly controversial and "religious" topic with most health-conscious men nowadays. But, regardless of your stance on total cholesterol, let me tell what does matter: LDL. And let me tell you why it matters. Most guys showing up on my site or on the Peak Testosterone Forum have significant cardiovascular issues, especially anyone over the age of 40. If you're over 40 and have lived a Western lifestlyle, your arteries have significantly hardened due to the eroding of the collagen content and the buildup of arteriosclerosis, i.e. arterial plaque.
Very few Westerners escape the rapid acceleratio of plaque buildup. One huge issue this causes is damage to the endothelium. What eventually happens is that the lining of your arteries, the endothelium, becomes so covered with plaque that it cannot pump out any signficant amount of nitric oxide. This leads to a host of issues including erectile dysfunction, high blood pressure and at times angina.
So one of the huge tasks facing most men is the get their arteries back. How can they do that? Simple: lowering LDL. Many studies and clinicians have recognized the importance of lowering LDL to reverse plaque. Yes, your arterial plaque can be actually reduced and blood flow increased.
NOTE: It's not just the Low Fat folks who insist on and outline how to decrease arterilsclerosis: it's also leading cardiologists such as William Davis and the Asteroid Study researchers mentioned below. (You can read more about the subject in my link on Clearing Your Arteries.)
"But wait!", you ask, "Isn't LDL cholesterol and I thought cholesterol doesn't matter?" Okay, admittedly, it doesn't matter to a healthy, younger male with little arterial plaque. However, the rest of us need some help and some arterial repair and need to face the facts. Consider the current evidence on the subject:
1. Your level of arteriosclerosis is related to cardiovascular events. And, yes, cardiovascular 'events' are not a good thing.
2. Decreasing arterial plaque (arteriosclerosis) improves cardiovascular risk.
3. Decreasing LDL to a certain threshold will reverse arteriosclersosis.
And that's the subject of this page. Just what LDL threshold does one need to go to actually begin to reverse his arteriosclerosis? Below I'll show you the levels given by various experts and researchers.
Want your arteries back? Want increased blood flow? Then focus on your LDL and quit listening to the "Cholesterol Myth" people. Remember that heart disease is the #1 killer of men in modern societies. Lowering LDL levels could almost completely eliminate this plague.
1. Dr. Caldwell Esselstyn. This physician was one of the early pioneers who showed that arterial plaque could indeed be reversed. In another link I reviewed his book, Prevent and Reverse Heart Disease, and in this book on page 67 he writes his target LDL levels with his patients:
"Here, once again, is the basic message of my research: no one who achieves and maintains total blood cholesterol of 150 mg/dl and LDL levels below 80 mg/dl - using strict plant-based nutrition and, where necessary, low doses of cholesterol-reducing drug - experiences progression of heart disease."quot;
Now, granted, in this quote he does not actually promise reversal of arteriosclerosis, but, in fact, his books has a number of photos and stories of people who have done just that.
2. Dr. Neal Bernard. I have also reviewed Dr. Bernard's low fat book on Reversing Diabetes (with a Low Fat, low glycemic diet) - another excellent book! - and Dr. Bernard suggests therein that some men may need to go even lower (p. 105):
"...many scientists are now pushing for stricter standards, including reductions to below 70 mg/dl (1.8 mmol/l) for high risk patients. Some authorities have called for lowering your LDL by 30 to 40 percent regardless of what your starting level is." 
3. 2007 Circulation Study. The journal Circulation looked at three different diets and found that the more the fat, the less the blood flow: "BART testing revealed a significant inverse correlation between flow-mediated vasodilation and intake of total fat (r2= 0.29; P=0.03), saturated fat (r2= 0.31; P=0.02) and monounsaturated fat (r2= 0.35; P=0.01)."  I am inserting this comment, because it's important to realize that fat slows down blood flow. A lot of you middle-aged guys are going to get big benefits in erectile strength from this. Can I hear an Amen, brother? And in this study, the Low Fat participants went down to an average LDL of 84.6 ng/dl.
4. Dr. Ornish. Probably the most famous Low Fat researcher is Dean Ornish. His landmark studies in the 80's showed that a Low Fat Diet could reverse heart disease and arteriosclerosis. In his bestselling book The Spectrum (p. 204) he wrote:
"If that's enough to bring it down to an LDL level less than 100 mg/dl, preferably below 70 mg/dl if you have heart disease, that may be sufficient."
NOTE: A Low Fat Diet has also been found improve to telomere aging, turns off 100's of prostate cancer genes, etc. and I discuss all of the list in link on The Incredible Health Benefits of a Low Fat Diet .
Now why would Dr. Ornish even mention an LDL as high as 100 mg/dl? The reason is that this book, The Spectrum, is built on the idea that one does not HAVE to be on a Low Fat Diet unless you have heart disease. If you do not have major cardiovascular problems, then you can get by more than likely with a more moderate approach.
But then notice the LDL target that Dr. Ornish gives after that: 70 mg/dl.This is low LDL indeed but underscores the importance of taking aggressive action if you have heart disease. Ornish's Low Fat programs can have a profound impact on men with heart disease. For example, one of his studies showed angina decreasing by 91% - a very impressive result to say the least. (p. 9)
5. Asteroid Study. This study gave patients high doses of statins and then tracked, based on their LDL levels, cardiovascular outcomes. LDL of 70 mg/dl was the level at which the authors felt that all cardiovascular goals were achieved. However, other commentators have noted that this study showed plaque reversal at about 60 mg/dl.
Now, because plaque reversal has been achieved at higher levels, one cannot help but wonder if some negative aspect of statins require one to go even lower than is necessary with Low Fat. This seems reasonable to me considering that statins decimate CoQ10 levels and raise arachidonic acid levels, both of which are heart unhealthy.  For more negatives, see my link on The Hidden Risks of Statins.
6. Dr. William Davis. Some people will trust Dr. Davis a little more, because he a) hates wheat, b) is not in love with Low Fat Diets and c) likes some fat in the form of omega-3's and monos. He has kind of been adopted by some in the Paleo crowd because of it, but what they don't realize is that in his book, Track Your Plaque, he advocates an LDL of 50-60 for those who want to decrease arteriosclerosis! 
As you can see there is some variation in what level of LDL you should shoot for. 85 mg/dl is the highest number advocated by someone who has actually achieved plaque reversal. But there is some evidence for men with serious issues that it needs to be lower, probably between 60 and 70.
So you (and your physician if he/she knows anything about the subject) have to decide for yourself. There are many unanswered questions:
How much does exercise play a role? Can certain superfoods (pomegranate juice, berries, etc.) play a role?
We will not know the answers to these kind of questions for probably years to come, so, in the meantime, one has to make an educated guess.
1) Diabetes Care, 2006, 29(suppl1):S4-S42, American Diabetes Assocation, "STandards of Medical CAre in Diabetes - 2006"
2) Circulation, 2007, 116:II_819, "Abstract 3610: Comparative Effects of 3 Popular Diets on Lipids, Endothelial Function and Biomarkers of Atherothrombosis in the Absence of Weight Loss"
3) American Journal of Cardiology, 2009, 104(1):29-35, "Safety and Efficacy of Achieving Very Low Low-Density Lipoprotein Cholesterol Levels With Rosuvastatin 40 mg Daily (from the ASTEROID Study0"
5) Nutr Metab Cardiovasc Dis, 2001 Apr, 11(2):88-94, "Statins enhance arachidonic acid synthesis in hypercholesterolemic patients"
6) Track Your Plaque, Dr. William Davis, p. 106.