The benefits, which were seen after only 14 weeks of regular consumption, “support a beneficial role for chronic nut consumption in sperm quality” may reflect a need to develop dietary recommendations that are more “male specific”.

The results of the study are presented today at the annual meeting of the European Society of Human Reproduction and Embryology.

According to Dr Albert Salas-Huetos from the Human Nutrition Unit of the Universitat Rovira i Virgil in Reus, Spain, who led the study, the research was performed against a background of general decline in quantity and quality of human sperm, attributed in industrialised countries to “pollution, smoking, and trends toward a western-style diet.”

Significant improvements

The study was a 14-week randomised clinical trial in which 119 healthy young men aged 18-35 were allocated to either their usual western-style diet supplemented with 60 g/day of mixed almonds, hazelnuts and walnuts, or their usual western-style diet without nuts.

Results showed significantly higher levels of sperm count, vitality, motility and morphology (shape) in the men randomised to the 60 g/day nut diet than in those following their usual diets free of nuts.

Improvements in the former group were by around 16% in sperm count, 4% in sperm vitality, 6% in sperm motility, and 1% in morphology (shape). These four parameters, explained Salas-Huetos, are all associated with male fertility.

These improvements were consistent with improvements found in other recent studies with diets rich in omega-3, antioxidants (eg, vitamin C and E, selenium and zinc), and folate. Nuts are dense foods containing many of these nutrients and other phytochemicals.

Benefits at the genetic level

The researchers, however also looked deeper into the DNA of the sperm to try and understand why the nuts might trigger these benefits. At the molecular level it has also been proposed that the genetic integrity of each sperm cell is essential for fertility. If DNA strands in the cell become damaged or fragmented, they will be unable or less likely to fertilise an egg and maintain embryonic development.

It is believed that this DNA fragmentation is caused by oxidative stress as a result of environmental and lifestyle factors.

In this study the men in the nut group also showed a significant reduction in their levels of sperm DNA fragmentation, a parameter closely associated with male infertility. The researchers propose that it is this change, at genetic level that is responsible for all the other benefits seen.

More to learn

The men in this study were generally healthy and exhibited no signs of infertility. The researchers say that a next step would be to look at the effects of regular nut eating on men with fertility problems.

Nevertheless Salas-Huetos concludes that “healthy lifestyle changes such as following a healthy dietary pattern might help conception – and of course, nuts are a key component of a Mediterranean healthy diet.”

Compared to a traditional, high-fat Western diet,  a healthier lower fat diet appeared to change the composition of their cell membranes in both the healthy cells and the cancer cells in the prostate.  The men also had lower levels of pro-inflammatory substances in their blood and a lower ‘cell cycle progression’ (CCP, an indication of how aggressively a cancer may spread), say researchers at the University of California Los Angeles (UCLA).

This study appears in the early online edition of Cancer Prevention Research and follows a 2011 study by Aronson and his team that found a low-fat diet with fish oil supplements eaten for 4-6 weeks prior to prostate removal slowed the growth of cancer cells in human prostate cancer tissue compared to a traditional, high-fat Western diet.

That short-term study also found that the men on the low-fat fish oil diet were able to change the composition of their cell membranes in both the healthy cells and the cancer cells in the prostate. They had increased levels of omega-3 fatty acids from fish oil and decreased levels of the more pro-inflammatory omega-6 fatty acids from corn oil in the cell membranes, which may directly affect the biology of the cells, Aronson said.

You are what you eat

“These studies are showing that, in men with prostate cancer, you really are what you eat,” said study lead author William Aronson, a clinical professor of urology at UCLA and chief of urologic oncology at the West Los Angeles Veterans Affairs Medical Center. “The studies suggest that by altering the diet, we may favorably affect the biology of prostate cancer.”

The men in the previous study were placed into one of two groups, the low-fat fish oil diet or the Western diet. The Western diet consisted of 40% of calories from fat, generally equivalent to what many Americans consume today. The fat sources also were typical of the American diet and included high levels of omega-6 fatty acids from corn oil and low levels of fish oil that provide omega-3 fatty acids.

The low-fat diet consisted of 15% of calories from fat. Additionally, the men on this diet took 5g of fish oil per day in five capsules, three with breakfast and two with dinner, to provide omega-3 fatty acids. Omega-3 fatty acids have been found to reduce inflammation, and may be protective for other malignancies.

Slowing cancer’s spread

For this study, the research team wanted to look at the potential biological mechanisms at work in the low-fat fish oil diet that may be providing protection against cancer growth and spread. They measured levels of the pro-inflammatory substances in the blood and examined the prostate cancer tissue to determine the CCP score.

“This is of great interest, as the CCP score in prostate cancer is known to be associated with more aggressive disease and can help predict which patients will recur and potentially die from their cancer,” Aronson said.

Further, Aronson and his team analyzed one pro-inflammatory substance called leukotriene B4 (LTB4) and found that men with lower blood levels of LTB4 after the diet also had lower CCP scores.

“Given this finding, we went on to explore how the LTB4 might potentially affect prostate cancer cells and discovered a completely novel finding that one of the receptors for LTB4 is found on the surface of prostate cancer cells,” Aronson said.

Further studies are planned to determine the importance of this novel receptor in prostate cancer progression.

• Earlier this year a study on essential fatty acids and prostate cancer was misleading reported in the media as showing that supplements of omega-3 fatty acids could promote aggressive prostate cancer. See here for our news analysis Essential fatty acids and prostate cancer – not quite the final word.

Studying the effects of fruits and vegetables on ‘motility’ (the ability of sperm to swim towards an egg), researchers concluded that carrots are the food that seems to carry the most health benefits.

For the study, which was published in the journal Fertility and Sterility, researchers used a questionnaire to survey the diets and supplement use of nearly 200 young, college-age men in the Rochester, New York. They also tested the quantity and quality of the men’s sperm.

Comparing data

Each man provided a semen sample which was analysed within half an hour for:

• semen volume
• sperm count
• sperm motility
• sperm morphology

From the food and supplement frequency questionnaire, the researchers were able to estimate the amount of the following micronutrients in the men’s diet:

• vitamin A
• vitamin C
• vitamin E
• carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein and lycopene)

With this data the researchers were able to look for links between the amount of each micronutrient consumed and semen quality.

Beta-carotene benefits

Increased carotenoid intake was associated with sperm that moved 6.5% faster compared with those from men with the lowest carotenoid intake. This association was higher if the intake came from food rather than supplements.

The sperm boosting effect of carrots was attributed to the carotenoids, especially beta-carotene which the body converts into vitamin A, which in turn can support sperm health and neutralise free radicals. The carotenoid lutein was found to have a similar benefit to sperm health.

Higher intake of lycopene, which is found in large amounts in tomatoes, was associated with 1.7% higher numbers of normally-shaped sperm compared with men with the lowest intake.

Interestingly, high intake of vitamin C (from food only) was associated with lower sperm count. The sperm concentrations were 22% lower than in the men with the least intake of vitamin C.

However moderate amounts of vitamin C in the diet produced the highest sperm concentration, count and motility. Vitamin C was not related to any change in sperm shape.

In this study no associations were seen with intake of vitamin A or E, and none of the results were affected by BMI or smoking status. However in an older population, as previous studies have shown, the effects of these things might have been more apparent.

Salad foods means better sperm

Three foods (carrots, lettuce and spinach) accounted for 59% of the beta-carotene intake and two foods (lettuce and spinach) accounted for 56% of the lutein. The majority (98%) of the lycopene was in five foods (tomato soup, tomato juice, salsa, ketchup and fresh tomatoes).

According to the researchers: “In a population of healthy young men, carotenoid intake was associated with higher sperm motility and, in the case of lycopene, better sperm morphology. Our data suggest that dietary carotenoids may have a positive impact on semen quality.”

But clean up your environment, too

Recent studies have indicated that average sperm count has decreased by more than half in western countries. Environmental toxins and physiological changes in the body, weight gain, a sedentary lifestyle, and high alcohol use, cell phones in pockets and estrogen in dairy products or water have all been linked to a decline in sperm health.

Apart from a diverse and antioxidant-rich diet, other ways to improve your sperm quality include:

• Quit smoking
• Try to achieve and/or maintain a healthy weight
• Exercise more
• Drink sensibly
• Keep your testicles cool
• Don’t put your laptop on your lap – or your mobile phone in your pants pocket
• Filter your water
• Eat organic food to avoid hormone disrupting pesticide residues

But unlike in women, neither soya protein nor a common antidepressant provides relief for men, according to US researchers.

 Hot flashes occur in approximately 80% of men who are undergoing hormone manipulation as treatment for prostate cancer. Hormone therapy (sometimes called androgen-deprivation therapy) reduces the levels of male hormones, called androgens, to prevent them from reaching prostate cancer cells and stimulating their growth.

A hard to treat side-effect

“Changing hormone levels cause hot flashes in both women and men, so we hoped that using soya supplements and/or an antidepressant would help reduce them in men as it does in many women,” said Mara Vitolins, DrPH, professor of public health sciences at Wake Forest Baptist Medical Centre in North Carolina, and lead author of the study, which is published in the online issue of the Journal of Clinical Oncology.

For this study, 120 men, aged 46 to 91, undergoing prostate cancer treatment were randomly assigned to one of four daily regimens over a 12 week period: placebo pill and milk powder; venlafaxine, an antidepressant commonly prescribed to treat hot flashes in women, and milk powder protein; soya protein powder and placebo pill; or venlafaxine and milk powder.

When assessing hot flash symptom severity and frequency and quality of life the researchers found that neither venlafaxine nor soya protein alone or in combination reduced hot flashes in men.

Men need better advice

While the triggers of hormone decrease differ for men and women, the symptoms of hot flashes are identical in both genders. That is, a sensation of warmth and flushing comes on suddenly—most intensely in the head and trunk areas. Heavy sweating and a reddening of the skin may accompany these symptoms.

Such symptoms may pass quickly, averaging about four minutes, and end in a cold sweat. Some men and women will experience these symptoms infrequently, while others may suffer from them up to 10 times a day.

 Most men stop having flashes within three to four months of finishing their androgen deprivation treatment Men who stay on the therapy may continue to suffer from symptoms.

Treating hot flashes in women can also be difficult – different women respond differently to treatments.  But says Vitolins, “Utilizing interventions that appear effective in decreasing hot flashes in women to treat men who have hot flashes has proven to be relatively ineffective.”

These findings , he suggests, highlight the need for continuing efforts to identify treatments for hot flashes that are specifically developed for men.

Non-drug options

This study focussed on medical approaches to men’s hot flashes. But because drug and supplement treatments can be hit and miss many women choose more practical non-drug options. There is no reason why these should not work for men too:

Food Avoiding caffeine, spicy foods, and alcohol can help lessen both the number and severity of hot flashes. In this study  soya supplements didn’t work for the men though some women find reducing fatty foods and incorporating more plant-based foods into their diets helpful. Eating a wide variety of vegetables is always a good idea anyway; specific sources of plant estrogens include: soybeans, chickpeas, lentils, flaxseed, grains, beans, fruits, red clover.  Recent evidence suggests that flaxseed may have other benefits in helping to reduce the recurrence and death rates from breast and prostate cancer.

Lifestyle Reducing the temperature in a room, dressing in layers, and the use of an electric fan can be effective ways to help deal with troublesome hot flashes. Being overweight can also make hot flashes more bothersome hot flashes, therefore weight loss can be helpful. Smokers tend to experience more hot flashes (and are at greater risk of certain cancers), so quitting is a good idea. Incorporating more exercise into your daily or weekly routine will also help – those who are sedentary seem to have more troublesome hot flashes.

Breathe. Stress can make symptoms worse. Find a self-calming skill to practice, such as yoga, meditation or slow, deep breathing.  Try deep, slow abdominal breathing (6 to 8 breaths per minute). Practice deep breathing for 15 minutes in the morning, 15 minutes in the evening and at the onset of hot flashes.

Sleep Keep the bedroom cool – and dark – to encourage comfortable sleep. Try keeping a small plant sprayer filled with water and a calming essential oil like lavender by the bedside for a cooling emergency spritz when you need it.