More than two thirds of American adults are overweight or obese. As the American waistline increases so does the epidemic of insulin resistance, metabolic syndrome and type 2 diabetes. The link between decreasing testosterone levels associated with these syndromes is well established in the scientific literature: men with diabetes have significantly lower levels of serum (blood) testosterone when compared with men without diabetes; as well men in the lowest levels of free testosterone have a four-fold increased risk of having diabetes when compared with men in the highest levels of free testosterone. We don’t know the exact mechanism between insulin resistance and low testosterone in men. Visceral adiposity (belly fat) also plays a role where the enzyme aromatase can convert testosterone into estrogen, which also decreases testosterone levels.

A recent study suggests that another mechanism may have a direct impact on testosterone levels: sugar consumption. A study with 74 men between the ages of 19-34 looked at the impact of 75g of glucose on serum (blood) total and free testosterone levels in men with varying glucose tolerance. Glucose ingestion was associated with a 25% decrease in mean testosterone levels regardless of glucose tolerance or BMI, and remained suppressed for 120 minutes. What is 75g of glucose equivalent to in real food terms? A can of Coca Cola has 75g, a McDonald’s M&M McFlurry has 84.8g, a cup of low-fat fruit yogurt has 46.7g, a Clif Z bar has 30g and a pumpkin spice latte (grande) has 50g of sugar. It’s easy to see how regular sugar consumption alone can add up to perpetually suppressed testosterone levels in men.

So what does this mean?  If you are concerned about your testosterone level, decrease or eliminate your sugar consumption.  Everyone knows we should eat less sugar, and here is one more reason we should do so.

Then have your testosterone levels measured with a saliva test, and be treated accordingly with physiologic dosing of bio-identical hormones, along with lifestyle changes, such as diet and exercise.

There's a new study out to add to the debate about testosterone replacement therapy in men and heart disease.  Does it increase or decrease the risk of heart disease?