Selenium Supplementation Does Not Affect Testicular Selenium Status or Semen Quality in North American Men

Abstract

Selenium (Se) is essential for sperm function and male fertility, but high Se intake has been associated with impaired semen quality. We reported previously a decrease in sperm motility in men fed high-Se foods, but we could not rule out the influence of other environmental and dietary factors. We now report on a randomized, controlled study on the potential adverse effects of Se supplementation on semen quality in 42 free-living men administered Se (300 mg/d) as high-Se yeast for 48 weeks. Semen analysis was performed 4 times before treatment began, then twice each week during treatment at 6, 12, 24, 36, and 48 weeks, and then after treatment at 72 and 96 weeks. Blood samples were collected 3 times before treatment and at each subsequent visit. Se concentration increased 61% in blood plasma and 49% in seminal plasma. However, Se supplementation had no effect on sperm Se, serum androgen concentrations, or sperm count, motility, progressive velocity, or morphology. We observed progressive decreases in serum luteinizing hormone, semen volume, and sperm Se in both the high-Se and placebo groups. Moreover, sperm straight-line velocity and percent normal morphology increased in Se-treated and placebo-treated participants. The lack of an increase in sperm Se suggests that testicular Se stores were unaffected, even though the participants' dietary Se intake was tripled and their total body Se approximately doubled by supplementation. These results are consistent with animal studies showing the Se status of testes to be unresponsive to dietary Se intake.

Nutritional modifications in male infertility: a systematic review covering 2 decades

“…Of the 23 included studies, 7 (n ¼ 1084 patients) evaluated the effect of dietary habits and food intake on semen parameters and quality, 2,25,28,48 4 (n ¼ 232 patients) evaluated the effect of carnitine consumption on sperm parameters and quality, 54-57 3 (n ¼ 148 patients) investigated the effect of selenium on sperm parameters, 58-60 2 (n ¼ 481 patients) evaluated the effect of coenzyme Q10 on sperm quality and parameters, 61,62 and each of the remaining articles investigated the effect of saffron, soybased foods, vitamin C, clomiphene citrate, n-3 polyunsaturated fatty acids, beta carotene, and ubiquinol on sperm parameters. [63][64][65][66][67][68][69] The 23 articles included patients from 9 different countries: Iran (6 articles), 2,[61][62][63]67,69 the United States (7 articles), 28,54,58,64,[70][71][72] Italy (3 articles), [55][56][57] Egypt (2 articles), 66,68 the United Kingdom (1 article), 60 Germany (1 article), 65 Poland (1 article), 59 Spain (1 article), 48 and Brazil (1 article). 25 …”

“…The single agents were saffron, 63 coenzyme Q10, 61,62,69 and selenium. 58,59 The average duration of the studies was 24 weeks.…”

“…2,25,28,48,63,64,[70][71][72] The remaining studies, which investigated the role of specific micronutrient(s) on indicators of semen quality, reported conflicting results (Table 3). 17,[54][55][56][57][58][59][60][61][62][65][66][67]69 Dietary habits and food intake. All 7 included studies that investigated the role of diet and food intake on sperm variables reported that diet plays a key role in the improvement of sperm parameters.…”

“…Two of the randomized control trials, by Iwanier and Zachara 59 and Hawkes et al, 58 investigated the effect of selenium consumption on sperm parameters, but neither reported a positive result. Selenium intake, neither 200 mg/d for 12 weeks 59 nor 300 mg/d for 48 weeks, 58 resulted in no significant improvement in sperm parameters.…”

Antioxidant therapy in male infertility: fact or fiction?

“…47,[50][51][52][53][54][55] Three RCTs evaluated the effects of selenium alone or in combination with N-acetyl cysteine and two of the three studies reported a significant improvement in sperm parameters in the treatment arm only. 43,48,54 Four RCTs evaluated the effects of L-carnitine alone or in combination with L-acetyl carnitine and three of the four reported a significant improvement in sperm parameters in the treatment arm only. 42,44,49,60 Three RCTs evaluated the effects of N-acetyl cysteine alone or in combination with selenium and all three reported a significant improvement in sperm parameters in the treatment arm only.…”