In addition, protein and carbohydrate amounts were shown to have an effect on sperm production and fertility in the speckled cockroach. Holidic diets were used which allowed for specific protein and carbohydrate measurements to be taken, giving it credibility. A direct correlation was seen in sperm number and overall of food intake. More specifically, optimal sperm production was measured at a 1:2 protein to carbohydrate ratio. Sperm fertility was best at a similar protein to carbohydrate ratio of 1:2. This close alignment largely factors in determining male fertility in "Nauphoeta cinerea". Surprisingly, sperm viability was not affected by any change in diet or diet ratios. It's hypothesized that sperm viability is more affected by the genetic makeup, like in the "good sperm hypothesis". These ratios and results are not consistent with many other species and even conflict with some. It seems there can't be any conclusions on what type of diet is needed to positively influence sperm competition but rather understand that different diets do play a role in determining sperm competition in mate choice.