STEP 1: Step 1 in any Prediabetes and Diabetes Reversal Program must start with the obvious: take an honest look at whether or not you have one of the conditions. Of course, diabetes is usually pretty obvious. However, prediabetes can be much more subtle and does not usually hit you like a storm. However, it is VERY common in Western societies and one set of researcher even called it a pandemic.  That may seem a bit dramatic, but, when you consider that about one fourth (of the U.S. population) has prediabetes, pandemic is clearly not an exaggeration.  For those who don't know, prediabetes is the condition where one begins to become insulin resistant. And, unfortunately, it is accompanied by a whole suite of negative symptoms that can take a man out of commission.
NOTE: Another term for prediabetes is Metabolic Syndrome or Met-S.
In my opinion, monitoring for prediabetes one of our top priorities, simply because the effects are so devastating. The problem is that you can live with Metabolic Syndrome for years, while it is silently destroying everything you hold dear as a male. Terms like Metabolic Syndrome may seem obscure, but let me give 5 Great Reasons You Do Not Want This Condition, regardless of the name:
a) Metabolic Syndrome is associated with apnea, depression, fatigue and other conditions that can affect your relationships and productivity.
b) Metabolic Syndrome causes endothelial dysfunction, i.e. it decreases blood flow and, therefore, will likely effect your erectile strength.  In fact, endothelial dysfunction is considered one of the early signs of Metabolic Syndrome, and, furthermore, men with Metabolic Dysfunction have an increased chance of erectile dysfunction. See my page Erectile Dysfunction Syndrome for more information.
c) Metabolic Syndrome, if it goes on long enough, often leads to full-fledged type II diabetes. One of the reasons for this is that, as you begin to lose your insulin sensitivity, your blood sugar levels can spike and fall. There is considerable evidence that these surges can actually damage the beta cells of the pancreas.
d) Metabolic Syndrome silently annihilates your arteries and cardiovascular system. I already mentioned the endothelial dysfunction that comes with it, but it also leads to a) higher triglycerides, b) lower HDL and c) greater LDL-P (or apoB). These all lead to increased arterial plaque and clots, which, of course, is perfect recipe for a heart attack or stroke. Think about it: prediabetes is almost designed to be the Perfect Killing Machine. It increases almost every risk factor you can think of for heart disease, and heart disease is the #1 killer of men. (The high blood pressure that comes with it often does the same.) 
e) Metabolic Syndrome is often associated with the beginnings of fatty liver disease. And, please, do not say "my liver markers were good, so I don't have fatty liver!" Read the section below on low SHBG and you will see this is an invaldi assumption.
So prediabetes is much more serious than most men realize. And, because the initial symptoms are often not incapacitating, many learn to live with it and even ignore it for years Doctors are rarely any help: most of them insist that early warning signs such as prehypertension and fasting blood glucose between 90 and 100 are a non-issue. The bottom line is that you usually have to take charge and watch for this silent killer yourself.
How do you it? The good news is that the research has uncovered some great warning signals. Here are Eight Early Signs of Prediabetes (Metabolic Syndrome):
1. Post-Meal Blood Glucose Surges. Most physicians will use fasting blood glucose or insulin as their primary gauge as to whether or not a man is struggling in these areas. However, research shows that your blood sugar post-meal (post-prandial) is much more predictive of future diabetes risk. This is a simple test that you can do at home and I discuss the latest research in my page How to Test for Insulin Resistance.
2. Low SHBG. I have been surprised to find just how many men on the Peak Testosterone Forum have low SHBG. Researchers found that men and women in the lowest quartile were almost twice as likely to develop diabets as those in the upper. The conclusions were that "low levels of circulating sex hormone-binding globulin (SHBG) are strongly predictive for Type 2 diabetes in women and men, report researchers in the New England Journal of Medicine." 
Why is this? SHBG is the binding protein to both testosterone and estradiol. It is produced almost entirely in the liver and so, if the liver is dysfunctional, SHBG can be negatively impacted. Because prediabetes often leads to dysfunctional liver cell function, SHBG is often pushed to very low levels.
What does prediabetes lead to altered liver cell function? You have to remember the root cause of insulin resistance: intramyocellular lipids. Basically, liver (and muscle) cells get stuffed with fats (from refined carbs, high fat meals and/or overeating). For more information, see my pages Low SHBG and How to Cure Low SHBG.
3. A1C (hbA1C). Glycated hemoglobin is one of those gifts of Mother Nature. This blood protein is basically a rolling average of your last 3 months of blood sugar. Levels between 5.7 and 6.4 are generally considered prediabetic and those 6.5 or greater are thought to be diabetic. This is a very simple test that can be done at home - you can buy kits at Walmart - or you can do it very inexpensively (without a doctors orders) through one of these labs sites: Inexpensive Testosterone Labs.
4. High Triglcyerides and Low HDL. One of the signs of prediabets are high triglcyerdies and low HDL. Of course, this is a double-edged sword, because high triglycerides will only worsen intramyocellular lipids and low HDL is needed to protect the lining of the arteries from plaque. What is the threshold? One study found that "Cardiometabolic risk factors were more adverse in men and women whose TG/HDL-C ratios exceeded 3.5 and 2.5, respectively, and approximately one third were identified as being IR...These findings suggest that the TG/HDL-C ratio may serve as a simple and clinically useful approach to identify apparently healthy, young individuals who are IR and at increased cardiometabolic risk." 
5. Fasting Glucose. Fasting glucose is something you can do at home or a doctor can order it for you. The current thinking among most docs is that fasting glucose between 100 and 125 is prediabetic and 125+ is diabetic. I think this kind of thinking could not be more wrong. Example: the man who had low SHBG in my How to Cure Low SHBG did not have fasting glucose over 100 and he took readings many times. In fact, he had none of the typical warning signs of prediabetes that doctor's like to use. The same is true monitoring post-meal glucose surges. Some men will be suprised to find they are insulin resistant using this test. Again, these are great tests to find if you are in the early stages.
6. Low Prolactin. SHBG is not the only thing negatively impacted by an insulin resistant state: prolactin can also drop precipitously. Of course, many men know that higher prolactin levels lower testosterone and libido, so they assume that low prolactin would a be a good thing. But, as is so often the case, there is a range for everything and prolactin is no exception. It turns out that when prolactin drops below about 4.5, it can be a significant signal that one is losing glucose and insulin control. See my page on Low Prolactin for more information.
7. Rising apoB (LDL-P or LDL Particle Count). Researchers have found that it's the traditional LDL measurement, LDL-C, that you so often get with an annual physical is not the most important marker for cardiovascular and arterial disease. An even better marker is something called the LDL Particle Count, or LDL-P. An alternative measurement of essentially the same thing is apoB. Basically, these markers directly tell you the concentration of LDL particle in the blood, and it is this concentration level that will determine if LDL is driven into the walls of your arteries.
What does all of that have to do with prediabetes? As mentioned above, when a man starts losing his insulin sensitivity, he will begin to produce more and smaller LDL particle numbers. (He also will produce more triglcyerides - see #4.) This in turn will raise his LDL-P and apoB. Men with Met-S can have staggeringly high numbers. What levels should you be at? See my pages LDL-P Particle Count Levels and Safe Levels of apoB for more information.
8. Unexplained High Blood Pressure. Some men will meausre their arterial plaque with an IMT or Heart Scan and find their have some plaque, but not enough to create the kind of blockages that would create a rise in blood pressure. Often they are fairly young as well and cannot figure out why they are struggling with blood pressure issues at such a young age. Well, one of the explanations can be Metabolic Syndrome. Prehypertension and hypertension are actual symptoms of Metabolic Sydnrome and is one of the things that savvy doctors look at in their evaluation.
1) Arteriosclerosis, Thrombosis, and Vascular Biology, 2008, 28:629-636, "Metabolic Syndrome Pandemic"
2) J Am Coll Cardiol, 2013 Aug 20, 62(8):697-703, "Prevalence and trends of metabolic syndrome in the adult U.S. population, 1999-2010"
3) Curr Hypertens Rep, 2005 Apr, 7(2):88-95, "Metabolic syndrome and endothelial dysfunction"
5) J Lipid Res, 2013 Oct, 54(10):2795-9, "Plasma triglyceride/HDL-cholesterol ratio, insulin resistance, and cardiometabolic risk in young adults"