Watermelon – Got Lycopene?

Did you know that watermelon, a summertime favorite fruit, is high in the antioxidant called lycopene?

While tomatoes are  most well known to be high in lycopene, lycopene is also found in watermelon and guava.  Lycopene, a carotenoid, has potential anti-prostate cancer properties as well as being pro-fertility (sperm shape) – it has up to twice the antioxidant capacity of β-carotene.  The mean lycopene concentration of watermelon is about 40% higher than for raw tomato, and watermelon ranks 5th among the major contributors of lycopene in the U.S. diet.

Research in the past few decades show that increasing blood levels of lycopene might lower triglyceride and LDL-cholesterol levels, thus lowering cardiovascular disease risk.

Bottom line: Don’t hesitate to have watermelon this summer!

Quit Smoking to Improve Male Fertility and Erection

Smoking and Male Fertility: Cigarette smoking (including second-hand by being near a smoker) may negatively affect a man’s semen. This is important especially if a man is trying to have children. Some studies have shown decreased sperm count (average approximately 20% decreased and based on how much one is exposed to), motility (movement), abnormal sperm shape and sperm maturation have been described (more). Smokeless tobacco is not any better and also has the same negative effect on semen parameters (more). Further cigarette smoking has been shown to change sperm DNA packaging and changes in gene expression which may certainly affect fertility (more).

Cigarette Smoking and Male Infertility and Erectile Dysfunction Just as DNA damage can occur in women’s eggs from smoking, it has been identified that sperm DNA may be bound directly by tobacco smoke components. Sperm additionally have increased chance of getting an extra Y chromosome (DNA) with increased concentrations of smoking byproducts in the urine (more). DNA damage is transmitted from parents who smoke (fathers may play a more significant role than mothers) to offspring and can lead to miscarriages and birth defects. Even for those couples that seek in vitro fertilization (where sperm and egg are united outside the body and then replaced in the female’s uterus), smokers require twice as many attempts to conceive as nonsmokers.

Smoking and Erection: Severity of erectile dysfunction (ED) significantly correlates with the level of exposure to smoking regardless of increased cardiovascular risk (more). ED has been reported in 3.7% of current smokers, 2.0% of former smokers, and 2.2% of men who never smoked. Quitting smoking could prevent ED worsening in 25% of cases. Cigarette smoking causes arterial tightening (constriction), with reduction in oxygen supply and increased damage to healthy tissues (called endothelial tissues). Within 24-36 hours of stopping smoking, the bloodflow characteristics were improved in one study (more).

Bottom Line: While the overall effect of smoking remains difficult to assess on men’s fertility (due to factors including partner issues and other unhealthy habits of smokers that cannot be sorted out with available studies), data exists to discourage smoking in couples that desire children. Stop smoking and improve not just your breathing and fertility, but also possibly your sex life.

For tips on quitting smoking, see the CDC (Centers for Disease Control, US Government) website. Due to popular request, we will soon be posting info on the cancer risks of smoking (including bladder and kidney cancer).

Tomatoes- Prostate Cancer and…Sperm Quality


Anti-oxidants such as pomegranate are often in the news for possible health benefits.  Lycopene is another anti-oxidant known as a carotenoid, which is most often found in tomatoes and tomato-based products.

Some older studies have identified decreased risks of various types of cancer (prostate, lung, stomach) with increased lycopene intake, while others did not show such a benefit.   Recently, however, multiple studies show that there is a likely benefit to including lycopene in your diet: a decreased risk of prostate cancer as well as improved sperm shape (morphology).

Semen quality and antioxidants:

You can read more about the effects of antioxidants such as lycopene on sperm quality in our blog post here.

Prostate cancer and lycopene:

In terms of prostate cancer risk, let ‘s discuss the evidence for this finding.  Specifically, a Harvard and Ohio State University study noted that increased dietary lycopene intake is associated with decreased risk of prostate cancer (10-25% decreased risk), including lethal forms (highest intake group had 28% decreased compared to lowest lycopene intake) of prostate cancer in a recent study of  nearly 50,000 male health professionals.  Earlier and higher lycopene intake is associated with improved outcomes including decreased blood vessel (angiogenic) growth in tumors.

systematic review from China in 2013 identified that the greatest raw tomato intake had a 19% decreased risk of prostate cancer vs. those with the lowest intake.  Cooked tomato intake also had benefit with a 15% decreased risk.

Another recent study from 2014 from Italy indicated that low lycopene levels in the prostate are most frequently associated with prostate cancer.  In this study, 32 men took 20-25 mg/day of lycopene for six months, and then had prostate biopsy.  Prostatic lycopene level was significantly lower among men with prostate cancer than in men with  prostatitis (inflammation) or HGPIN (which is a pre-cancerous prostatic tissue).  Nearly 78% of the men with prostate cancer had a lycopene level <1 ng/mg, while only 6% of the HGPIN men  and none of the men with prostatitis had such a low lycopene level in the prostate.

While increased lycopene consumption seems to be beneficial, additional study of prostatic levels and intake should be studied in a variety of populations to confirm these findings.