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Associations of Fish Oil Supplement Use With Testicular Function in Young Men

Jensen TK, Priskorn L, Holmboe SA, Nassan FL, Andersson AM, Dalgård C, Petersen JH, Chavarro JE et al.

JAMA network open, 2020

1,679 participants

Abstract

IMPORTANCE: Many young men have poor semen quality, and the causes are often unknown. Supplement intake of ω-3 polyunsaturated fatty acid has been found to improve semen quality among men with infertility, but the association with semen quality among healthy men is unknown.

OBJECTIVE: To determine if intake of ω-3 fatty acid supplements is associated with testicular function as measured by semen quality and reproductive hormone levels among healthy men.

DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study included young Danish men from the general population recruited between January 1, 2012, and December 31, 2017, at compulsory examinations to determine their fitness for military service. Young unselected men were approached after the examination and invited to participate in a study of reproductive function, regardless of their fitness for military service. Data analysis was conducted from September 1, 2018, to June 30, 2019.

EXPOSURES: Intake of supplements, including fish oil, during the past 3 months.

MAIN OUTCOMES AND MEASURES: Semen quality, measured as volume, concentration, total sperm count, percentage of morphologically normal spermatozoa, and motility, and serum reproductive hormone levels, measured as follicle-stimulating hormone, luteinizing hormone, testosterone, free testosterone, and inhibin B levels.

RESULTS: Among 1679 young Danish men (median [interquartile range] age, 18.9 [18.7-19.4] years) recruited to participate, 98 men (5.8%) reported use…

How strong is the evidence?

Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design. Reported size: 1,679 participants or records.

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