Sugar and arachidonic acid encourage the production of pro-inflammatory hormones. When the problem in male fertility is an obstruction to the "plumbing" that carries the mature sperm to the prostate gland to be incorporated into semen, then inflammation is bad and relieving inflammation is good. Eating less sugar and fewer high-fat protein foods encourages the production of anti-inflammatory hormones that may permit more sperm to reach the prostate gland. Avoiding sugar is also keenly important when female infertility is due to PCOS, also known as polycystic ovarian syndrome. Although the symptoms of PCOS are tied to the overproduction of testosterone, the overproduction of testosterone is connected to insulin resistance, a condition that can be relieved by consuming less sugar. The way this works is that some kind of stress an injury, a long illness, or just years of unrelieved stress raises blood sugars long enough that cells start to shut out sugar to prevent free radical damage.
When cells burn a lot of sugar, they produce a lot toxic byproducts, so they resist the efforts of insulin to carry sugar out of the bloodstream into the cell. The ovaries, however, are never insulin resistant. Sugar flows into the unimpeded. All the extra energy makes the ovaries work overtime, and one of the results of additional ovarian activity is an excess of testosterone. Insulin resistance is such a major factor in this form of female infertility that reducing sugar consumption just enough for 2 to 5 pounds of weight loss often is enough to enable conception. Although avoiding sugar is never a guarantee for couples trying to conceive, couples that eat healthy are far more likely to have children sooner than those who do not.