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That's right - when thinking about having children, don't just focus on the women's age. Think about sperm quality also. From Science Daily:

Men's sperm quality declines with age, review of 90 studies confirms

Conflicting evidence about the extent to which men's semen quality declines with age -- likely lowering their fertility -- is being cleared up by new research that has collated and reviewed data from 90 previous studies from around the world.

After conducting a systematic review and meta-analysis of the studies' data, researchers from the University's Departments of Zoology and Anatomy found consistent age-related declines in semen volume and sperm performance and increases in malformed and DNA-damaged sperm. Semen quality is regarded as a proxy for how fertile a male is.

"The effects of declining semen traits with increasing male age have largely been ignored due to inconsistencies in the literature, but our work now suggests that male age affects a variety of traits. It is well recognised that reduced sperm performance can affect pregnancy success, but it is less well known that the quality of the sperm, particularly DNA quality, could affect the development and health of the offspring," Dr Johnson says.

"Our study made no attempt to estimate the rate of decline, but some well-controlled clinic-based studies have observed consistent declines with increasing age, whereas others project declines after age 35 for some traits and after age 40 for others" she says.

"Older males contribute to increased risk of obstetric complications, miscarriage, and offspring disorders such as autism, Down syndrome, epilepsy, and schizophrenia. In addition, increasing male age may be an overlooked component of couple infertility, leading to our increased use and dependency on fertility treatments, such as IVF."

The authors suggest that clinical analysis of the percentage of DNA-fragmented sperm cells and a greater focus on how well sperm swim may lead to better patient outcomes during fertility treatments of aging couples."These are likely more accurate and consistent predictors of a man's fertility status than commonly clinically measured traits such as semen volume, sperm concentration and total sperm count," Dr Johnson says.

Sperm under microscope. Credit: Fertility Associates Ltd. NZ

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Please note that the study was of people living in the Baltimore, Maryland area - so it is unknown if this would hold true for people living elsewhere. From Medical Xpress;

Virus may affect mental abilities, study reports

People with an algae virus in their throats had more difficulty completing a mental exercise than healthy people, and more research is needed to understand why, US scientists say. A study in the Proceedings of the National Academy of Sciences showed that the virus was present in about half of 92 human subjects studied, and those who had it performed worse on certain basic tasks.

The virus, known as Acanthocystis turfacea Chlorella virus 1, or ATCV-1, also appeared to limit the cognitive abilities of mice.The mice had a harder time navigating a maze and noticing new objects in their surroundings after they were infected.

It remains unclear if the virus was truly driving the drop in mental functioning. Researchers have not yet shown the cause and effect between the virus and the intelligence results."At this point we do not think that this virus should be considered as a threat to individual or public health," said lead researcher Robert Yolken, a virologist at Johns Hopkins University in Baltimore, Maryland. The virus was found by accident while scientists were analyzing microbes in the throats of healthy humans for a different study.

Experts have been studying viruses similar to ATCV-1 for 35 years, said senior author James Van Etten of the University of Nebraska, an expert on algal viruses. Van Etten joined the research four years ago when Johns Hopkins scientists found ATCV-1's DNA sequences in the brain tissue of people who had died with mental disorders such as schizophrenia.

"These viruses are ubiquitous in fresh water ponds and streams throughout the world," Van Etten said. He noted that the virus—previously thought to only infect algae—could make its way into the human body when people swallow water while swimming.There might also be another host in nature, such as mosquito larvae, he said. But the nature of the disease is still in the early stages of analysis.

It is also unknown if the virus's effects on the brain are lasting or temporary. Scientists have long understood that viruses interact with DNA, and further studies could shed more light on the role of the virus on cognition.

"As more studies like this are conducted, I believe we'll find out there's even more interaction between viruses, bacteria and fungi that are either ingested or breathed into our noses and mouths and the overall human condition," said Jordan Josephson, ear nose and throat specialist at Lenox Hill Hospital in New York, who was not involved in the study.

Further information on this study and the virus. From Medical Xpress:

Researchers identify algae-virus DNA in humans

From Newsweek:

American Researchers Discover 'Stupidity Virus'

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Natural ways that may help GERD symptoms without drugs : eating smaller portions, losing weight, not lying down for 2 hours after eating, and avoiding alcohol, cigarettes, and "trigger" foods.From Health Day News:

Could Popular Heartburn Drugs Upset Your 'Good' Gut Bugs?

Heartburn drugs such as Prilosec and Nexium may disrupt the makeup of bacteria in the digestive system, potentially boosting the risk of infections and other problems, a small new study suggests.

According to Harvard Medical School, billions of dollars are spent annually on antacid drugs in an attempt to combat heartburn, ulcers and gastroesophageal reflux disease, also known as GERD. Old standbys such as Maalox and Mylanta have been supplanted by more effective, more expensive drugs, including proton pump inhibitors. These include Prevacid (lansoprazole) and Protonix (pantoprazole) in addition to Prilosec (omeprazole) and Nexium (esomeprazole).

Long-term use of proton pump inhibitors has been linked to infection with a germ called Clostridium difficile, which causes severe diarrhea, he said. Researchers have also connected the medications to vitamin deficiencies, bone fractures and pneumonia, among other conditions.

In the new study, researchers sought to understand what happens to the trillions of germs in the digestive system when people take omeprazole, the generic name for the drug best known as Prilosec.Ten participants, aged 18 to 57, took 20 or 40 milligrams of the drug a day for 28 days. Researchers analyzed the study participants' stool samples to understand the germs in their guts.

"These microbes have evolved with us to participate in our normal development and metabolism, and perform certain functions that we would not be able to accomplish without their help," DiBaise said. Many scientists believe that people's risk of disease goes up when their normal germ makeup changes, he said.

The researchers found evidence that the medications disrupted the balance of bacteria in the digestive systems of the participants, and the changes lasted for at least a month after they discontinued the drug. It didn't seem to matter whether they took the higher or lower dose, DiBaise said.

DiBaise cautioned that the study doesn't prove that the drug causes users to become more vulnerable to C. difficile infections. However, it shows that the drug "creates a situation in the gut microbial environment that may increase an individual's susceptibility," he said.

What should users do for now? According to DiBaise, proton pump inhibitors are "the most effective medications to treat gastroesophageal reflux disease." If patients don't have the most severe symptoms, he said, other types of heartburn drugs might help. Also recommended: eating smaller portions, losing weight, not lying down for two hours after eating, and avoiding alcohol, cigarettes and "trigger" foods.

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Based on the study results, the researchers suggest that even older couples in bad marriages could benefit from marriage counseling.From Science Daily:

Bad marriage, broken heart?

Older couples in a bad marriage -- particularly female spouses -- have a higher risk for heart disease than those in a good marriage, finds the first nationally representative study of its kind.

Liu analyzed five years of data from about 1,200 married men and women who participated the National Social Life, Health and Aging Project. Respondents were aged 57-85 at the beginning of the study...Liu set out to learn how marital quality is related to risk of heart disease over time, and whether this relationship varies by gender and/or age. Among her findings:

Negative martial quality (e.g., spouse criticizes, spouse is demanding) has a bigger effect on heart health than positive marital quality (e.g., spousal support). In other words, a bad marriage is more harmful to your heart health than a good marriage is beneficial.

The effect of marital quality on cardiovascular risk becomes much stronger at older ages. Over time, the stress from a bad marriage may stimulate more, and more intense, cardiovascular responses because of the declining immune function and increasing frailty that typically develop in old age, Liu said.

Marital quality has a bigger effect on women's heart health than it does on men's, possibly because women tend to internalize negative feelings and thus are more likely to feel depressed and develop cardiovascular problems, Liu said.

Heart disease leads to a decline in marital quality for women, but not for men. This is consistent with the longstanding observation that wives are more likely to provide support and care to sick husbands, while husbands are less likely to take care of sick wives.

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Bottom line: Try to avoid artificial sweeteners!

From Scientific American: Artificial Sweeteners May Have Despicable Impacts on Gut Microbes

I find it ironic that Thanksgiving coincides with American Diabetes Month. In honor of that irony, two recently published studies have suggested a possible link between what you eat, how it impacts the behavior of the microbes living in your gut, and type II diabetes.

Results from a study by researchers in Israel, published in the journal Nature in October, have suggested that consumption of artificial sweeteners—found in over 6,000 food products—can lead to changes in the gut microbiome, and have put forth an explanation for how this alteration might be associated with diseases such as type II diabetes.

Jotham Suez, a PhD candidate and lead author of the study explains, “We asked people who do not regularly consume artificial sweeteners to add them to their diet for one week, and saw that the majority of these subjects had poorer glycemic responses.” And like humans, mice that were given saccharin-spiked water also developed marked glucose intolerance compared to mice drinking sugar water, or water alone.

Their experiment revealed that mice did exhibit different microbiome profiles after consuming artificial sweeteners, just as with the human volunteers who had developed glucose intolerance. And importantly, the humans who did not show glucose intolerance after consuming artificial sweeteners also did not see changes in the community composition of their microbiome.

Consequently, this change in microbial community in mice also modified how the microbiota functioned as a group to regulate metabolism. Pathways that impact the transport of sugar in the body were found to have decreased function after saccharin treatment and, notably, there was an increased abundance of short-chain fatty acids (SCFAs), which are implicated in lipid biosynthesis.

An investigation done by an independent group of researchers in Canada found similar results in a study published in October in the journal PLoS ONE. Although conducted using rats instead of mice, and with a different artificial sweetener (aspartame instead of saccharin) this study also found an increased risk of glucose intolerance. In addition, both studies showed that propionate—a SCFA highly involved in sugar production—is increased in animals consuming artificial sweeteners (although, unfortunately, propionate concentrations in humans weren’t assessed in the Nature study).

But the take home point is this: findings from two independent studies suggest that messing with the microbiome may have despicable consequences. Artificial sweeteners were originally intended to stave off the increasing obesity and metabolic disease epidemic, but instead they may have directly contributed to it.

In other words, consuming artificial sweeteners appears to throw metabolism out of whack by upsetting the critical balance of the biota in the gut—just as how chaos would surely ensue if you were to throw Gru’s minions out of whack.

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Great reasons to eat walnuts. Yes, this study was done in mice, but it (as supported by other research) should also apply to humans.From Medical Xpress:

'Tis the season to indulge in walnuts

Researchers at UC Davis and other institutions have found that diets rich in whole walnuts or walnut oil slowed prostate cancer growth in mice. In addition, both walnuts and walnut oil reduced cholesterol and increased insulin sensitivity. The walnut diet also reduced levels of the hormone IGF-1, which had been previously implicated in both prostate and breast cancer. The study was published online in the Journal of Medicinal Food. 

Davis and colleagues have been investigating the impact of walnuts on health for some time. A previous study found that walnuts reduced prostate tumor size in mice; however, there were questions about which parts of the nuts generated these benefits. 

In the current study, researchers used a mixture of fats with virtually the same fatty acid content as walnuts as their control diet. The mice were fed whole walnuts, walnut oil or the walnut-like fat for 18 weeks. The results replicated those from the previous study. While the walnuts and walnut oil reduced cholesterol and slowed prostate cancer growth, in contrast, the walnut-like fat did not have these effects, confirming that other nut components caused the improvements - not the omega-3s.

While the study does not pinpoint which combination of compounds in walnuts slows cancer growth, it did rule out fiber, zinc, magnesium and selenium. In addition, the research demonstrated that walnuts modulate several mechanisms associated with cancer growth.

"The energy effects from decreasing IGF-1 seem to muck up the works so the cancer can't grow as fast as it normally would," Davis said. "Also, reducing cholesterol means cancer cells may not get enough of it to allow these cells to grow quickly." In addition, the research showed increases in both adiponectin and the tumor suppressor PSP94, as well as reduced levels of COX-2, all markers for reduced prostate cancer risk.

Although results in mice don't always translate to humans, Davis said his results suggest the benefits of incorporating walnuts into a healthy diet. Other research, such as the PREDIMED human study, which assessed the Mediterranean diet, also found that eating walnuts reduced cancer mortality.

Still, Davis recommends caution in diet modification. "In our study the mice were eating the equivalent of 2.6 ounces of walnuts," he said. "You need to realize that 2.6 ounces of walnuts is about 482 calories. That's not insignificant, but it's better than eating a serving of supersized fries, which has 610 calories. In addition to the cancer benefit, we think you also get cardiovascular benefits that other walnut research has demonstrated.

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Are probiotic bacteria the reason?

From Medical Xpress: Does a yogurt a day keep diabetes away?

A high intake of yogurt has been found to be associated with a lower risk of developing type 2 diabetes, according to research published in open access journal BMC Medicine. This highlights the importance of having yogurt as part of a healthy diet.

Type 2 diabetes is a chronic condition that occurs when the body doesn't produce enough insulin, or the body's cells develop resistance to insulin. There is an increased risk of developing it if a relative has the condition or if an individual has an unhealthy lifestyle. 

Researchers from Harvard School of Public Health pooled the results of three prospective cohort studies that followed the medical history and lifestyle habits of health professionals. These studies were the Health Professionals' Follow-up Study (HFPS), which included 51,529 US male dentists, pharmacists, vets, osteopathic physicians and podiatrists, aged from 40 to 75 years; Nurses' Health Study (NHS), which began in 1976, and followed 121,700 female US nurses aged from 30 to 55 years; and Nurses' Health Study II (NHS II), which followed 116,671 female US nurses aged from 25 to 42 years beginning in the year 1989.

Within the three cohorts 15,156 cases of type 2 diabetes were identified during the follow-up period. The researchers found that the total dairy consumption had no association with the risk of developing type 2 diabetes. They then looked at consumption of individual dairy products, such as skimmed milk, cheese, whole milk and yogurt. When adjusting for chronic disease risk factors such as age and BMI as well as dietary factors, it was found that high consumption of yogurt was associated with a lower risk of developing type 2 diabetes.

The authors then conducted a meta-analysis, incorporating their results and other published studies, up to March 2013, that investigated the association between dairy products and type 2 diabetes. This found that consumption of one 28g serving of yogurt per day was associated with an 18 per cent lower risk of type 2 diabetes.

Previous research has suggested calcium, magnesium, or specific fatty acids present in dairy products may lower the risk of type 2 diabetes. It has been shown that probiotic bacteria found in yogurt improves fat profiles and antioxidant status in people with type 2 diabetes and the researchers suggest this could have a risk-lowering effect in developing the condition. 

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Amazing persistence of the restroom microbial community.From NPR news:

What Microbes Lurked In The Last Public Restroom You Used?

The invisible world of the bathroom isn't pretty — unless you're a microbe. After scanning the microbial zoo of four public restrooms recently, a team of researchers found a diverse swarm of characters that persisted for months despite regular cleaning of the facilities. The goal of the study, published in the December issue of Applied and Environmental Microbiology, was to better understand how communities of bacteria and viruses can shift in these very public places across a couple of months.

To get their down-and-dirty readings, the researchers selected four bathrooms at San Diego State University... They checked two women's restrooms and two men's restrooms (a high-traffic and a low-traffic bathroom for each gender). The bathrooms were thoroughly cleaned at the study's start with bleach solution, which killed any existing germ communities.Then, during the following hours, days, weeks and months of human use, the researchers periodically swabbed soap dispensers, floors and toilet seats in all four restrooms for microbe samples. 

Within one hour of sterilization, the bathrooms were completely recolonized with microbes — just as plants rapidly arrive and populate a newly emerged island. Fecal bacteria dominated, including on toilet seats and on soap dispensers — about 45 percent of the bacteria there were of fecal origin.

In all, the scientists found genetic traces of more than 77,000 distinct types of bacteria and viruses. (At least some of those species were likely dead or dormant, the scientists add; genetic testing detects them all, whatever their status.)

Patterns of regrowth and succession, as some species waned and others replaced them, were surprisingly similar from bathroom to bathroom; within just five hours the population mix in each room stabilized.

When the team tried growing cultures from different surfaces in each room, they found one set of live bacteria in overwhelming abundance: Staphylococcus. Staph's persistence in these studies points to its power as a potential pathogen, Gilbert says. Various versions are common on human skin and inside the nose and other orifices; they generally cause no problems, or trigger only minor skin infections. But staph infections can be serious, or even kill, if the bacteria get into bloodstream, joints, bones, lungs or heart. 

Gilbert notes that none of the live Staph strains detected in the San Diego bathrooms showed signs of being antibiotic resistant. They were instead relatively harmless "skin bugs that happened to have lost their skin," he says. The team did find genes from MRSA hiding on the floor, as well as traces of some troublemaker viruses, including HPV and herpes virus.

Interestingly, although restrooms that were left open for use for up to two months were cleaned regularly with soap and water, the communities of microbes found there remained relatively unchanged for the full eight weeks of the study.

No need to be scared or grossed out by that finding, Gilbert says..."All human environments contain pathogens — your bedroom, the phone you're talking on, even the bugs inside of you could turn pathogenic at any time," Gilbert tells Shots. "But we desperately need them in our lives." Having a healthy community of good — or even just neutral — microbes can crowd out the bad ones. As we've learned from using broad-spectrum antibiotics in the human body, "sterilization is not necessarily good," he says. "Bacteria come back right away, and they might come back perturbed."

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Jogging? Now retirees planning to relax and putter around instead have to jog for health? From Science Daily:

Jogging keeps you young: Seniors who run regularly can walk as efficiently as 20-somethings

A new study by researchers at Humboldt State University and the University of Colorado, Boulder is shedding light on an unexpected benefit of jogging in older adults. The study looked at adults over the age of 65 -- some of whom walk for exercise and some who run for exercise. The researchers found that those who run at least 30 minutes, three times a week were less likely to experience age-related physical decline in walking efficiency than those who simply walked.

In fact, the older runners were 7-10 percent more efficient at walking than those who didn't jog. "What we found is that older adults who regularly participate in high aerobic activities -- running in particular -- have what we call a lower metabolic cost of walking than older, sedentary adults. In fact, their metabolic cost of walking is similar to young adults in their 20s," said Justus Ortega, a Kinesiology Professor at Humboldt State and director of HSU's Biomechanics Lab.

Metabolic cost is the amount of energy needed to move and naturally increases as we age. High metabolic cost contributes to making walking more difficult and tiring. Decline in walking ability is a key predictor of morbidity in older adults.

In the study, researchers looked at self-reported older joggers over the age of 65 -- those who ran at least 30 minutes a day, three times a week -- and self-reported walkers, those who walked three times a week for 30 minutes. Participants were asked to walk on a treadmill at three speeds (1.6, 2.8 and 3.9 miles per hour) as researchers measured their oxygen consumption and carbon dioxide production. Overall, older joggers were 7-10 percent more efficient at walking than older adults who just walked for exercise. Their metabolic cost was similar to young people in their 20s.

Researchers aren't yet sure what makes joggers more efficient than walkers but they believe it may have something to do with the mitochondria found in cells. Evidence suggests that people who exercise vigorously have healthier mitochondria in their muscles.

 And a related concern: what about my knees? From  Science Daily:

Running does not lead to knee osteoarthritis, may protect people from developing disease, experts say

Running as a habitual exercise at any stage in life not only does not increase a person’s risk of developing knee osteoarthritis and may even help protect a person from developing the painful disease, according to new research findings."This {research} does not address the question of whether or not running is harmful to people who have pre-existing knee OA," said Dr. Lo. "However, in people who do not have knee OA, there is no reason to restrict participation in habitual running at any time in life from the perspective that it does not appear to be harmful to the knee joint."

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Big question: will vitamin D supplementation prevent cognitive decline? And what should be a daily supplement dose for adults? An earlier post cited a Medscape article suggesting that taking 1000 IU of vitamin D3 daily would be a good daily level of supplementation. From Medscape:

Vitamin D Deficiency Predicts Cognitive Decline

A new study supports a link between low levels of vitamin D and increased risk for cognitive decline, prompting calls for clinical trials to test whether vitamin D supplementation may delay or prevent dementia. In a group of cognitively intact older adults, serum 25-hydroxyvitamin D (25OHD) levels below 75 nmol/L at the outset predicted cognitive decline over roughly the next 4 years, independent of other factors.

For this analysis, the researchers looked at data on 1927 community-dwelling elderly individuals (mean age, 73.9 years) participating in the Italian population-based cohort study, Progetto Veneto Anziani (Pro.V.A.).

Dr Toffanello and colleagues say studies are needed to evaluate whether vitamin D supplementation might help to delay the cognitive decline, especially in patients who already have cognitive impairment.

David J. Llewellyn, PhD, from the University of Exeter Medical School in the United Kingdom, who has studied vitamin D and cognitive function but wasn't involved in this study, agrees. He told Medscape Medical News that this new study "effectively replicates" a 2010 study by his group showing a link between low vitamin D levels and an increased risk for cognitive decline. He said the Pro.V.A . study results are also consistent with a study his group published just this year inNeurology. That study suggested older patients with vitamin D levels below 50 nmol/L have about a 122% increased risk for dementia compared with those with higher levels.