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Published on Leave a comment on Oral Contraceptives, Pregnancy, and Birth Defects

This is an issue that a lot of women I've known over the years have wondered about: if a woman gets pregnant while on birth control pills (oral contraceptives) - and many women do - does it mean higher rates of birth defects? This study says NO to higher rates of major birth defects which is very reassuring, but it doesn't answer the issue of more subtle effects (e.g., behavioral effects) from the hormones in the contraceptives. From Medical Xpress:

Oral contraceptive use not associated with increased birth defects risk

Oral contraceptives taken just before or during pregnancy do not increase the risk of birth defects, according to a new study by researchers from Harvard T.H. Chan School of Public Health and the Statens Serum Institut in Denmark. They found that the prevalence of major birth defects was consistent (about 25 per 1,000 live births) across all pregnant women in the study population regardless of contraceptive use.

Even though oral contraceptives are more than 99% effective with perfect use, almost 10% of women become pregnant within their first year of use. Many more women will stop using oral contraceptives when planning a pregnancy and conceive within a few months. Little is known about the potential health effects to children from in utero exposure to the hormones in oral contraceptives.

....Charlton and colleagues were able to tap into a wealth of data collected from multiple Danish health registries between 1997 and 2011 and linked by the unique personal identification number assigned to all Denmark residents. The researchers looked at 880,694 live-born infants, and the health of these children at one-year follow-up. Oral contraceptive use was estimated based on the date of the mother's most recently filled prescription.  Among the women in the study population, a fifth had never used oral contraceptives before becoming pregnant, and more than two-thirds had stopped using oral contraceptives at least three months before becoming pregnant. Eight percent had discontinued use within three months of becoming pregnant, and 1%, or well over 10,000 women, had used oral contraceptives after becoming pregnant.

The prevalence of birth defects was consistent across each category of oral contraceptive use, and remained so when the researchers added in pregnancies that ended as stillbirths or induced abortions.

Published on Leave a comment on Higher Leukemia Risk With Lower Levels of Sunshine and Vitamin D?

 The following research finds a link (it doesn't establish cause) - but these interesting associations with vitamin D keep popping up. The research looked at leukemia rates in 172 countries and found that living closer to the equator (and assumed to have higher levels of vitamin D due to sunlight exposure) is linked to lower levels of leukemia. By far the best source of vitamin D is sunshine (and not food). From Medical Xpress:

Researchers link higher risk of leukemia to low sunlight and vitamin D

Epidemiologists at University of California, San Diego School of Medicine report that persons residing at higher latitudes, with lower sunlight/ultraviolet B (UVB) exposure and greater prevalence of vitamin D deficiency, are at least two times at greater risk of developing leukemia than equatorial populations.

These results suggest that much of the burden of leukemia worldwide is due to the epidemic of vitamin D deficiency we are experiencing in winter in populations distant from the equator," said Cedric Garland, DrPH, adjunct professor in the Department of Family Medicine and Public Health and member of Moores Cancer Center at UC San Diego Health. "People who live in areas with low solar ultraviolet B exposure tend to have low levels of vitamin D metabolites in their blood," Garland said. "These low levels place them at high risk of certain cancers, including leukemia."

According to the American Cancer Society, 54,270 cases and 24,450 deaths from leukemia occur in the United States alone each year. There is no known way to prevent most types of leukemia, though some types may be prevented by avoiding high doses of ionizing radiation, exposure to the chemical benzene, smoking and certain types of chemotherapy.

The UC San Diego study analyzed age-adjusted incidence rates of leukemia in 172 countries from GLOBOCAN, an international agency for research on cancer that is part of the World Health Organization, comparing that information with cloud cover data from the International Satellite Cloud Climatology Project. The study follows similar investigations by Garland and colleagues of other cancers, including breast, colon, pancreas, bladder and multiple myeloma. In each study, they found that reduced UVB radiation exposure and lower vitamin D levels were associated with higher risks of cancer.

Leukemia rates were highest in countries relatively closer to the poles, such as Australia, New Zealand, Chile, Ireland, Canada and the United States. They were lowest in countries closer to the equator, such as Bolivia, Samoa, Madagascar and Nigeria.

Published on Leave a comment on Sugar in Western Diet and Breast Cancer

This study was done in mice, but...it may apply to humans. The researchers found that sugar intake in mice comparable with levels in Western diets (in humans) led to increased breast tumor growth and metastasis.They specifically found that table sugar and high fructose corn syrup "was responsible for facilitating lung metastasis and 12-HETE production in breast tumors" in mice. So, at the very least, think about eliminating high fructose corn syrup from the diet - read labels and definitely eliminate soda (a huge source of added high fructose corn syrup).From Science Daily:

Sugars in Western diets increase risk for breast cancer tumors and metastasis

The high amounts of dietary sugar in the typical Western diet may increase the risk of breast cancer and metastasis to the lungs, according to a study at The University of Texas MD Anderson Cancer Center.The findings, published in the Jan. 1, 2016 online issue of Cancer Research, demonstrated dietary sugar's effect on an enzymatic signaling pathway known as 12-LOX (12-lipoxygenase).

"We found that sucrose intake in mice comparable to levels of Western diets led to increased tumor growth and metastasis, when compared to a non-sugar starch diet," said Peiying Yang, Ph.D., assistant professor of Palliative, Rehabilitation, and Integrative Medicine. "This was due, in part, to increased expression of 12-LOX and a related fatty acid called 12-HETE." Previous epidemiological studies have shown that dietary sugar intake has an impact on breast cancer development, with inflammation thought to play a role.

"The current study investigated the impact of dietary sugar on mammary gland tumor development in multiple mouse models, along with mechanisms that may be involved," said co-author Lorenzo Cohen, Ph.D., professor of Palliative, Rehabilitation, and Integrative Medicine. "We determined that it was specifically fructose, in table sugar and high-fructose corn syrup, ubiquitous within our food system, which was responsible for facilitating lung metastasis and 12-HETE production in breast tumors." Cohen added that the data suggested that dietary sugar induces 12-LOX signaling to increase risks for breast cancer development and metastasis.

Identifying risk factors for breast cancer is a public health priority, say the authors. The researchers state that moderate sugar consumption is critical, given that the per capita consumption of sugar in the U.S. has surged to over 100 lbs. per year and an increase in consumption of sugar-sweetened beverages has been identified as a significant contributor to an epidemic of obesity, heart disease and cancer worldwide.

The MD Anderson team conducted four different studies in which mice were randomized to different diet groups and fed one of four diets. At six months of age, 30 percent of mice on a starch-control diet had measurable tumors, whereas 50 to 58 percent of the mice on sucrose-enriched diets had developed mammary tumors. The study also showed that numbers of lung metastases were significantly higher in mice on a sucrose- or a fructose-enriched diet, versus mice on a starch-control diet.

Published on Leave a comment on Phthalates, Sperm, and Miscarriages

More and more negative news about phthalates: men with greater exposure to DEHP (a phthalate) have lower sperm motility (how the sperm move or their ability to swim), and pregnant women with higher levels of phthalates have a higher rate of pregnancy loss (miscarriages - mainly between 5 and 13 weeks of pregnancy). Phthalates are found in many plastics, are thought to be endocrine disruptors, and can be measured in urine. From Medical Xpress: Lower sperm motility in men exposed to common chemical

Men with higher exposure to the substance DEHP, a so-called phthalate, have lower sperm motility and may therefore experience more difficulties conceiving children, according to a Lund University study. Phthalates is an umbrella term for a group of substances based on phthalic acid, some of which are suspected to be endocrine disruptors. Many phthalates are found in soft plastics in our daily surroundings.... Since phthalate molecules leak out of plastics, we are exposed to it daily and absorb the chemicals through food, drink, skin contact and inhalation. 

"We have studied metabolite levels of the phthalate DEHP (diethylhexyl phthalate) in urine as an indicator of exposure, as well as the semen quality of 300 men between the ages of 18 and 20. The results show that the higher metabolite levels the men had, the lower their sperm motility was", says Jonatan Axelsson, researcher at the Department of Laboratory Medicine, Lund University. For the one quarter of the men with the lowest levels of exposure, 57 per cent of the sperm cells were moving forward, compared to 46 per cent for the quarter of the men with the highest levels of exposure.

As previous research has reported that there is a linear connection also between sperm motility and chances of becoming pregnant, the findings could indicate that the more exposed one is to DEHP, the smaller the chances are of having children.

From Medical Xpress:  Exposure to phthalates could be linked to pregnancy loss

A new study of more than 300 women suggests that exposure to certain phthalates—substances commonly used in food packaging, personal-care and other everyday products—could be associated with miscarriage, mostly between 5 and 13 weeks of pregnancy. 

Out of concern over the potential health effects of phthalates, the U.S. has banned six of these substances from use in certain products made for young children. But many are still included as ingredients in paints, medical tubes, vinyl flooring, soaps, shampoos and other items. Research on phthalates has shown that long-term exposure to low levels of the some of these compounds harms lab animals' health and can increase their risk for pregnancy loss. Additionally, at least one study found that female factory workers exposed to high levels of phthalates through their work were at a higher risk for miscarriage.

The researchers tested urine samples from 132 women who had miscarriages and 172 healthy pregnant women in China. They found pregnancy loss was associated with higher levels of urinary phthalate metabolites from diethyl phthalate (DEP), di-isobutyl phthalate (DiBP) and di-n-butyl phthalate (DnBP). Although this doesn't prove that phthalates cause pregnancy loss, the study suggests an association exists that the researchers say should be studied further.

Published on Leave a comment on We Are Absorbing Some Air Pollutants Through Our Skin

When we think about air pollution, we usually think about pollutants in the air that we breathe in. But there is a growing body of evidence that some pollutants found in the air, including a group of chemicals called phthalates, can be absorbed directly through the skin (dermal absorption or dermal intake). A recent study has found that the skin absorption of certain phthalates (DERP and DnBP) is comparable to that from inhalation.

Phthalates are linked to a number of negative health effects, and so we should try to minimize our exposure to them.(Oct. 8, 2015 post and Sept. 29, 2015 post). The findings of this study is another strong argument against using scented products in the home, because phthalates are found in fragrances - whether air fresheners, scented candles, perfumes, dryer sheets, etc. Just think of them as indoor air pollution. From Environmental Health Perspectives:

Transdermal Uptake of Diethyl Phthalate and Di(n-butyl) Phthalate Directly from Air: Experimental Verification

Fundamental considerations indicate that, for certain phthalate esters, dermal absorption from air is an uptake pathway that is comparable to or greater than inhalation. Yet this pathway has not been experimentally evaluated and has been largely overlooked when assessing uptake of phthalate esters.This study investigated transdermal uptake, directly from air, of diethyl phthalate (DEP) and di(n-butyl) phthalate (DnBP) in humans.  ...continue reading "We Are Absorbing Some Air Pollutants Through Our Skin"

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Two recent studies found health problems associated with low levels of vitamin D: higher risk of stress fractures and also increased severity of IBS (Irritable Bowel Syndrome) symptoms. From Science Daily:

Low levels of vitamin D may increase risk of stress fractures in active individuals

Vitamin D plays a crucial role in ensuring appropriate bone density. Active individuals who enjoy participating in higher impact activities may need to maintain higher vitamin D levels to reduce their risk of stress fractures, report investigators in The Journal of Foot & Ankle Surgery.

The role of vitamin D in the body has recently become a subject of increasing interest owing to its many physiologic effects throughout multiple organ systems. Vitamin D is an essential nutrient that can behave as a hormone. It is obtained through diet and through the skin when exposed to the sun's rays. It is essential for bone development and remodeling to ensure appropriate bone mass density. Low levels of vitamin D can lead to osteoporosis, osteomalacia, decreased bone mineral density, and risk of acute fracture.

Investigators tested the serum concentration of 25(OH)D, which is used to determine vitamin D status, in patients with confirmed stress fractures....Using the standards recommended by the Vitamin D Council (sufficient range 40 to 80 ng/mL), more than 80% of these patients would have been classified as having insufficient or deficient vitamin D levels. According to the standards set by the Endocrine Society (sufficient range 30 to 100 ng/mL), over 50% had insufficient levels.

"Based on these findings, we recommend a serum vitamin D level of at least 40 ng/mL to protect against stress fractures, especially for active individuals who enjoy participating in higher impact activities," explained Dr. Miller. "This correlates with an earlier study of 600 female Navy recruits who were found to have a twofold greater risk of stress fractures of the tibia and fibula with a vitamin D level of less than 20 ng/mL compared with females with concentrations above 40 ng/mL.

From Science Daily: Large proportion of IBS sufferers are vitamin D deficient

A large proportion of people living with Irritable Bowel Syndrome (IBS) are vitamin D deficient, a new study has found. Researchers from the University of Sheffield discovered a significant association between a patient's vitamin D levels and the severity of their IBS symptoms, particularly the extent to which IBS affects their quality of life.

The study, which is the first of its kind, found that out of 51 IBS patients tested 82 per cent exhibited insufficient vitamin D levels....IBS is a chronic and debilitating functional disorder of the gastrointestinal (GI) tract which affects around 10-15 per cent of the western population. Little is known about why and how the condition develops, although it is known that diet and stress can make symptoms worse. 

Published on Leave a comment on Traditional Toys and Books Better Than Electronic Toys For Young Children

More evidence that traditional toys and books are superior to electronic toys in both verbal parent-child interactions and non-verbal interactions for young children. Parent-child verbal interactions are so important because they teach young children language, lay the groundwork for literacy skills, teach role-playing, teach emotional and social skills such as turn-taking and accepting others' leads. In other words, put down the electronic gadgets and go spend time talking and interacting with your young child with old style traditional toys and books. From Science Daily:

How does type of toy affect quantity, quality of language in infant playtime?

Electronic toys for infants that produce lights, words and songs were associated with decreased quantity and quality of language compared to playing with books or traditional toys such as a wooden puzzle, a shape-sorter and a set of rubber blocks, according to an article published online by JAMA Pediatrics.

Anna V. Sosa, Ph.D., of Northern Arizona University, Flagstaff, and colleagues conducted a controlled experiment involving 26 parent-infant pairs with children who were 10 to 16 months old. Researchers did not directly observe parent-infant play time because it was conducted in participants' homes. Audio recording equipment was used to pick up sound. Participants were given three sets of toys: electronic toys (a baby laptop, a talking farm and a baby cell phone); traditional toys (chunky wooden puzzle, shape-sorter and rubber blocks with pictures); and five board books with farm animal, shape or color themes.

While playing with electronic toys there were fewer adult words used, fewer conversational turns with verbal back-and-forth, fewer parental responses and less production of content-specific words than when playing with traditional toys or books. Children also vocalized less while playing with electronic toys than with books, according to the results.

Results also indicate that parents produced fewer words during play with traditional toys than while playing with books with infants. Parents also used less content-specific words when playing with traditional toys with their infants than when playing with books. The authors note results showed the largest and most consistent differences between electronic toys and books, followed by electronic toys and traditional toys.

"These results provide a basis for discouraging the purchase of electronic toys that are promoted as educational and are often quite expensive. These results add to the large body of evidence supporting the potential benefits of book reading with very young children. They also expand on this by demonstrating that play with traditional toys may result in communicative interactions that are as rich as those that occur during book reading. ... However, if the emphasis is on activities that promote a rich communicative interaction between parents and infants, both play with traditional toys and book reading can be promoted as language-facilitating activities while play with electronic toys should be discouraged," the study concludes.

EDITORIAL: "Electronic toys that make noises or light up are extremely effective at commanding children's attention by activating their orienting reflex. This primitive reflex compels the mind to focus on novel visual or auditory stimuli. The study by Sosa in this issue of JAMA Pediatrics suggests that they may do more than just command children's attention; they appear to reduce parent-child verbal interactions. Why does this matter? Conversational turns during play do more than teach children language. They lay the groundwork for literacy skills, teach role-playing, give parents a window into their child's developmental stage and struggles, and teach social skills such as turn-taking and accepting others' leads.

Verbal interactions of course are only part of the story. What is missing from this study is a sense of how nonverbal interactions, which are also an important source of social and emotional skills, varied by toy type," write Jenny S. Radesky, M.D., of the University of Michigan Medical School, Ann Arbor, and Dimitri A. Christakis, M.D., M.P.H., of Seattle Children's Hospital and a JAMA Pediatrics associate editor, in a related editorial.

Published on Leave a comment on What Else Do Children Need From Their Parents?

The results of this study lead me to say DUH...of course spending time with children and being responsive to them, talking and interacting a lot with them, being affectionate and loving with them is best. So in this holiday season, don't just give gifts and toys to your children and think you can leave them to their own devices  or with others, but spend time with them, talk a lot to them, play games with them, interact, and do things with them. Put down your own electronic devices (cell phone, laptop, tablet, etc) and go spend time with your child. From Science Daily:

Parent touch, play and support in childhood vital to well-being as an adult

Did you receive affection, play freely and feel supported in childhood? Childhood experiences like these appear to have a lot to do with well-being and moral capacities in adulthood. In a forthcoming article in the journal Applied Developmental Science, University of Notre Dame professor of psychology Darcia Narvaez and colleagues Lijuan Wang and Ying Cheng, associate professors of psychology, show that childhood experiences that match with evolved needs lead to better outcomes in adulthood.

According to Narvaez, one of the reasons that the well-being of children in the United States lags behind that of children in other advanced nations is because "we have forgotten that we are social mammals with specific evolved needs from birth."

"Humans evolved with a nest of care for their young that matches up with the maturational schedule of the child. It was shaped over 30 million years ago and modified through human evolution," Narvaez said. "We call it the evolved developmental niche." In describing this niche, Narvaez emphasizes six components: Soothing, naturalistic perinatal experiences; responsiveness to a baby's needs including sensitivity to the signals of the baby before the baby cries; constant physical presence with plenty of affectionate touch; extensive breastfeeding; playful interactions with caregivers and friends; and a community of affectionate, mindful caregivers.

Narvaez, Wang and Cheng asked adults to reflect on their childhoods according to several components of the evolved developmental niche (EDN): How much did they receive physical affection? Play freely outside and inside? Do things as a family inside and outside the home? Feel supported?

Adults who report receiving more of such parenting practices in their childhoods display less depression and anxiety, greater ability to take the perspective of others and an orientation toward compassion. Adults who report less of these parenting practices in their childhood have poorer mental health, more distress in social situations and are less able to take another's point of view.

"Our research shows that when we don't provide children with what they evolved to need, they turn into adults with decreased social and moral capacities," Narvaez said. "With toxic stress in childhood, the good stuff doesn't get a chance to grow and you become stress reactive. It's hard to be compassionate when you are focused on yourself. We can see adults all around us who were traumatized or undercared for at critical times." In prior research, Narvaez and her colleagues found that children who experienced more of the evolved developmental niche exhibit, for example, more empathy, self-control and conscience.

Published on Leave a comment on Most Cancers Are Not Due to Bad Luck

After the nonsense of the study published earlier in the year and the resulting media coverage stating that most "cancer is due to bad luck", it is great to read this recent research disputing the earlier study's conclusions.  The new study concludes that bad luck accounts for only a small portion of cancers (10% to 30%), and that "external factors", such as environmental toxins, behaviors, and infections, account for the vast majority (90% to 70%) of cancers. Of course. From Medscape:

Most Cancers Are Not Due to 'Bad Luck'

This year began with the media buzzing over a study that suggested many cancer types can be chalked up to "bad luck." As the year draws to a close, a new study that reanalyzed some of the previous data concludes that bad luck accounts for only a small portion ― up to a third ― of cancers, and that external factors, such as environmental toxins and behaviors, account for the vast majority (90% to 70%).

As previously reported by Medscape Medical News, researchers from Johns Hopkins University, Baltimore, Maryland, reported that in about two thirds (22 of the 31) of cancer tissue types that they had investigated, the development of cancer could be largely explained by the bad luck of random mutations that arise during DNA replication in normal nonmalignant stem cells. The new study, published in Nature, challenges those findings and instead states that there is much more at stake than just a bout of bad luck.

A team led by Yusuf Hannun, MD, director of the Stony Brook University Cancer Center, in New York, found that intrinsic or internal risk factors contribute only modestly ― less than approximately 10% to 30% of lifetime risk ― to cancer development. Their research concluded that instead, cancer risk is heavily influenced by extrinsic or external factors, such as environmental toxins, behaviors, and infections.

"We used four distinct analytic approaches to assess cancer risk," Dr Hannun told Medscape Medical News. "Interestingly, each of the approaches used different datasets, and all of them came up with similar conclusions — that 70% to 90% of cancer risk seems to be attributed to extrinsic factors, and this is more in line with what we've seen with epidemiologic studies.

The original study on bad luck was published in Science on January 2 and immediately generated quite a bit of discussion, scrutiny, and opinion pieces, as well as many questions regarding the methods and calculations used in the study. Even the International Agency for Research on Cancer, the World Health Organization's specialized cancer agency, issued a press release saying that it "strongly disagrees with the conclusion" and warned that the message could harm cancer research and public health.

However, the authors found that this pattern was rare, and they determined that intrinsic factors played a vital role in only about 10% of cancers. In support of this finding are epidemiologic data, such as those that show that immigrants who move from countries with lower cancer incidence to countries with higher rates generally acquire the higher risk as they become more assimilated into their new country.

Second, the authors analyzed recent studies on mutational signatures in cancer and found that the majority of cancers, including colorectal, lung, bladder, and thyroid cancer, express mutations that are likely caused by extrinsic factors.Third, analysis of data from the Surveillance, Epidemiology, and End Results Program showed that for many cancers, incidence and mortality have been increasing, suggesting that external factors contribute heavily.

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We can't see them, but we all have little face mites that live in our faces, specifically in hair follicles. The scientific name of the face mites: Demodex folliculorum. There are at least 4 lineages of face mites that correspond to different regions of the world. Good thing they're harmless (we think).Gross but fascinating. From Wired:

Your Face Is Covered in Mites, and They’re Full of Secrets

WHEN YOU LOOK in the mirror, you’re not just looking at you—you’re looking at a whole mess of face mites. Yeah, you’ve got ‘em. Guaranteed. The little arachnids have a fondness for your skin, shoving their tubular bodies down your hair follicles, feeding on things like oil or skin cells or even bacteria. The good news is, they don’t do you any harm. The better news is, they’ve got fascinating secrets to tell about your ancestry.

New research out today in the Proceedings of the National Academy of Sciences reveals four distinct lineages of the face mite Demodex folliculorum that correspond to different regions of the world. African faces have genetically distinct African mites, Asian faces have Asian mites, and so too do Europeans and Latin Americans have their own varieties. Even if your family moved to a different continent long ago, your forebears passed down their brand of mites to their children, who themselves passed them on down the line.

Looking even farther back, the research also hints at how face mites hitchhiked on early humans out of Africa, evolving along with them into lineages specialized for certain groups of people around the planet. It seems we’ve had face mites for a long, long while, passing them back and forth between our family members and lovers with a kiss—and a little bit of face-to-face skin contact.

Leading the research was entomologist Michelle Trautwein of the California Academy of Sciences, who with her colleagues scraped people’s faces—hey, there are worse ways to make a living—then analyzed the DNA of all the mites they’d gathered. “We found four major lineages,” says Trautwein, “and the first three lineages were restricted to people of African, Asian, and Latin American ancestry.”

The fourth lineage, the European variety, is a bit different. It’s not restricted—it shows up in the three other groups of peoples. But Europeans tend to have only European mites, not picking up the mites of African, Asian, or Latin American folks. (It should be noted that the study didn’t delve into the face mites of all the world’s peoples. The researchers didn’t test populations like Aboriginal Australians, for instance, so there may be still more lineages beyond the four.)

So what’s going on here? Well, ever since Homo sapiens radiated out of Africa, those four groups of people have evolved in their isolation in obvious ways, like developing darker or lighter skin color. But more subtly, all manner of microorganisms have evolved right alongside humans. And with different skin types come different environments for tiny critters like mites.