I’m sure you know too much sugar is bad for you. But it seems every day I learn something new about the negative effects of eating (or drinking) too much of it. We know, for example, that sugar and refined carbohydrates causes inflammation, and I’m convinced this (inflammation) is the main culprit in cardiovascular disease (even more so than cholesterol).

Here’s something you may not know–sugar can temporarily suppress testosterone. I can point to at least one study that confirmed this:

Researchers were interested in knowing whether or not men tested for hypogonadism (low testosterone) should be tested in a fasted state. 74 men were given 75 grams of glucose (the standard dose for a glucose tolerance test). Their hormone levels were monitored at 30 minute increments after taking the sugar. They found that testosterone levels were suppressed by as much as 25% and remained so at the two-hour mark (120 minutes). All subjects experienced this suppression, regardless of whether or not they had other health issues related to glucose tolerance (diabetes, etc.). Some subjects had normal testosterone levels, yet the suppression caused enough drop to (temporarily) put them in the same range as men who suffer from hypogonasism.1

We do have to keep a few things in mind here: the drop in testosterone was transient, this is only one study, and insulin is an anabolic hormone in its own right.

But I didn’t realize just how drastically one insulin spike can affect other hormone levels. Drinking sweet drinks all day could negatively affect your testosterone levels (in addition to the other health issues). A 20-ounce soda on an empty stomach would pretty much duplicate the conditions of this study (a bottle would have 65 grams of sugar).

This is another reason I like the Renegade Diet style of eating. It seems limiting your intake of carbohydrates/sugar throughout the day is a reasonable strategy for optimizing your testosterone levels.

Reference:

1.Clin Endocrinol (Oxf). 2013 Feb;78(2):291-6. doi: 10.1111/j.1365-2265.2012.04486.x.

Abrupt decrease in serum testosterone levels after an oral glucose load in men: implications for screening for hypogonadism.