Researchers from the University of Sheffield found that a diet supplement containing a compound from tomatoes can improve the quality of sperm.
To better understand the role of dietary factors in the quality of semen, researchers from the University of Sheffield enlisted 60 healthy males, aged 19-30, who were recruited and randomized in this double-blind, placebo-controlled parallel study. Sperm and blood samples were collected at the beginning and end of the trial. The participants either received 14 mg lactolycopene a day (the equivalent of two tablespoons of concentrated tomato puree) or a placebo for 12 weeks.
Lycopene is an antioxidant that gives many red fruits and vegetables, such as radishes, beets and watermelon their pigment. But because dietary lycopene is poorly absorbed by the human body, the compound used in the Sheffield trial is a commercially available formulation called lactolycopene, created by supplement manufacturer Cambridge Nutraceuticals Ltd.
The research team found that it is possible to increase the proportion of healthy shaped (morphology) sperm and boost 'fast swimming' (motility) sperm by about 40%. The discovery could transform the way male infertility is treated by reducing the need for invasive fertility treatments in the future. Of all infertility cases, approximately 40-50% are due to "male factor" infertility, according to NBCI.
The study concluded that supplementation of 14 mg/day of lactolycopene improves sperm motility and morphology in healthy young men.
"We didn't really expect that at the end of the study there would be any difference in the sperm from men who took the tablet versus those who took the placebo. When we decoded the results, I nearly fell off my chair," said Professor Allan Pacey, the lead author and world-renowned expert in male reproduction.
"The improvement in morphology -- the size and shape of the sperm, was dramatic. We used a computer system to make these measurements, which takes a lot of the human error out of the results. Also, the person using the computer didn't know who had taken LactoLycopene and who had taken the dummy pills either.”
"This was the first properly designed and controlled study of the effect of LactoLycopene on semen quality, and it has spurred us to want to do more work with this molecule."
"We were surprised by the improvement in sperm quality shown by the results," said Dr. Liz Williams, who designed the trial.
More studies are in the pipeline
While the results offer hope, the study only involved healthy participants and does not show that lycopene improves fertility. Further studies are needed to be replicated with men with poor sperm quality.
"This was a small study and we do need to repeat the work in bigger trials, but the results are very encouraging. The next step is to repeat the exercise in men with fertility problems and see if LactoLycopene can increase sperm quality for those men and whether it helps couples conceive and avoid invasive fertility treatments,” added Williams.
Professor Pacey, who also heads the University of Sheffield’s department of oncology and metabolism, said the work so far has not investigated the mechanism for Lycopene's beneficial action but it is a known powerful antioxidant, so is potentially inhibiting the damage caused by oxidation of sperm which is a known cause of male fertility problems. He believes this antioxidant effect is key in producing the improvements in sperm quality seen in the trial, and is hoping to investigate this more.
The research team said they are hoping to embark on the new study as soon as possible.
European Journal of Nutrition
2019; doi: 10.1007/s00394-019-02091-5
A randomized placebo-controlled trial to investigate the effect of lactolycopene on semen quality in healthy males
Authors: Williams, E.A., et al.