An interventional study of Walnuts and OTC multivitamin in Oligozoospermia, Asthenozoospermia and Teratozoospermia, sponsored by University of California, Los Angeles. Completed at 2 sites in United States. Open to male participants aged 21 Years and older. Per ClinicalTrials.gov, last updated 2026-03-13.
Sponsored by University of California, Los Angeles · Not applicable, Interventional, and Treatment
The investigators are testing the hypothesis that two ounces of whole-shelled walnuts/day added to the diet of men seeking care for infertility will beneficially affect sperm parameters and fertility. The investigators will compare the walnut intervention to the commonly suggested recommendation of adding an OTC multivitamin supplement to the diet.
Purpose: The investigators are testing the hypothesis that two ounces of whole-shelled walnuts/day added to the diet of men with oligo- astheno- or teratospermia will beneficially affect sperm parameters. The investigators found in a previous study (Robbins et al. 2012, Biology of Reproduction 87(4):101, 1-8.) that walnuts added to a Western diet improved sperm parameters in healthy, young men of unknown fertility and the most improvement occurred in participants with poor sperm parameters at baseline. The investigators now test the walnut dietary intervention in a fertility clinic population known to have poor sperm parameters. The investigators will compare the walnut intervention to the usual care suggestion of adding an OTC multivitamin supplement to the diet. Neither walnuts nor the OTC multivitamin have been tested for efficacy in this fertility clinic population previously.
Methods: A randomized, parallel two-group, dietary intervention trial with single-blind masking of outcome assessors will be conducted with up to 140 men who present for fertility work-up with semen parameters below the 25th centile for count, and 10th centile for motility and/or morphology according to the WHO 5th Edition, Laboratory Manual for the Processing and Examining of Human Semen, 2010. Repeated measures at baseline and 12 weeks include: semen analyses (primary outcome), blood fatty acid/ nutrient profiles (secondary outcomes); IPAQ physical activity questionnaire and IIEF index of erectile function (potential modifiers or confounders). Dietary intake will be assessed throughout using 24-hour ASA dietary recall x 5 and fertility assessed by questionnaire at one year post enrollment.
64 studies on the registry are indexed under Oligospermia; 17 are open to participants now.
This study's enrollment of 80 is above the median of 65 across 46 interventional studies indexed under Oligospermia.
Browse Oligospermia studies →University of California, Los Angeles is the lead sponsor of 1,170 studies on the registry; 195 are open to participants now.
Of its 95 completed or terminated interventional studies of FDA-regulated products, 70 (74%) have results posted.
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Exclusion Criteria:
2 ounces whole-shelled walnuts per day for 12 weeks
Dietary Supplement: Walnuts
OTC multivitamin tablet 2 per day for 12 weeks
Dietary Supplement: OTC multivitamin
Sperm count
Change from baseline to three months in sperm count
Time frame: 12 weeks
Sperm motility
Change from baseline to 12 weeks in sperm motility
Time frame: 12 weeks
Sperm morphology
Change from baseline to 12 weeks in sperm morphology
Time frame: 12 weeks
Fertility
Fertilization of ova through natural conception or assisted reproductive technology
Time frame: 12 months
Blood fatty acid and nutrient profile
Change from baseline to 12 weeks in blood fatty acid profile and nutrients
Time frame: 12 weeks
Sperm aneuploidy
Change from baseline to 12 weeks in sperm aneuploidy
Time frame: 12 weeks
Sperm DNA strand breakage
Change from baseline to 12 weeks in sperm DNA integrity
Time frame: 12 weeks
Physical Activity
IPAQ (International Physical Activity Questionnaire) assessment of change from baseline to 12 weeks
Time frame: 12 weeks
Sexual function
IIEF (International Index of Erectile Function) assessment of change from baseline to 12 weeks
Time frame: 12 weeks
Dietary intake
ASA-24 (Automated Self-administered) 24-hour dietary recalls x 5 over 12 weeks
Time frame: 12 weeks
The record gives a start of May 2014, a primary completion of Mar 2020 and a completion of Mar 2020. It does not say whether these dates are actual or estimated.
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This study is completed, as verified in Nov 2020. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Walnut
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