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Ethics, In the News, Sports, Stanford News, Women's Health

Arguing against sex testing in athletes

Arguing against sex testing in athletes

Testosterone does not a man – nor a woman – make. So argues Stanford medical anthropologist Katrina Karkazis, PhD, in a New York Times op-ed today. She cites evidence against the scientific and ethical soundness of sex-testing policies used since 2011 by sports governing organizations including the International Olympic Committee, the Fédération Internationale de Football Association and the International Association of Athletics Federations.

From the piece:

Rather than trying to decide whether an athlete is “really” female, as decades of mandatory sex tests did, the current policy targets women whose bodies produce more testosterone than is typical. If a female athlete’s T level is deemed too high, a medical team selected by the sport’s governing bodies develops a “therapeutic proposal.” This involves either surgery or drugs to lower the hormone level. If doctors can lower the athlete’s testosterone to what the governing bodies consider an appropriate level, she may return to competition. If she refuses to cooperate with the investigation or the medical procedures, she is placed under a permanent ban from elite women’s sports.

Sports authorities argue that screening for high T levels is needed to keep women’s athletics fair, reasoning that testosterone improves performance. Elite male athletes generally outperform women, and this difference has been attributed to men’s higher testosterone levels. Ergo, women with naturally high testosterone are thought to have an unfair advantage over other women.

But these assumptions do not match the science. A new study in Clinical Endocrinology fits with other emerging research on the relationship between natural testosterone and performance, especially in elite athletes, which shows that T levels can’t predict who will run faster, lift more weight or fight harder to win. The study, of a sample of 693 elite athletes, revealed a significant overlap in testosterone levels among men and women: 16.5 percent of the elite male athletes had testosterone in the so-called female range; nearly 14 percent of the women were above the “female” range.

Karkazis concludes, “Barring female athletes with high testosterone levels from competition is a solution to a problem that doesn’t exist. Worse, it is pushing young women into a choice they shouldn’t have to make: either to accept medically unnecessary interventions with harmful side effects or to give up their future in sports.”

Previously: Is the International Olympic Committee’s policy governing sex verification fair?, Researchers challenge proposed testosterone testing in select female Olympic athletes and Gender ambiguity gets attention

In the News, Research, Sleep

Sleep: More important than ever?

Sleep: More important than ever?

A headline today caught my eye: “It’s Time to Pay Attention to Sleep, the New Health Frontier.” (Since installing a sleep-tracking app on my phone, I’ve been playing with different bed times, forms of exercise and other factors to measure their effects on sleep time and quality.) Anyway, the piece, on Time.com, explains why sleep’s importance to health is more serious than many of us really acknowledge. And it offers this bit of historical perspective on why now is the time to pay attention:

According to a 2013 Gallup survey, 40% of Americans get less than the recommended seven to eight hours a night. While the typical person still logs about 6.8 hours of sleep per night, that’s a drop from the 7.9 Americans were getting in the 1940s.

Previously: Exploring the benefit of sleep appsSleep on it: The quest for rest in the modern hospital, Mobile devices at bedtime? Sleep experts weigh in and Stanford doc talks sleep (and fish) in new podcast

Medical Education, Stanford News, Videos

High schoolers share thoughts from Stanford’s Med School 101

High schoolers share thoughts from Stanford's Med School 101

Scenes from this year’s Med School 101: In the video above, three high-school students describe their interests in science and the sessions they attended at Stanford Medicine’s recent daylong event for local teens. One of the presenters, Anand Veeravagu, MD, also weighed in, saying: “I really wanted to share with them my journey from graduating high school all the way to being a neurosurgery resident and what that involves.” (A lot of training!)

For those interested in seeing more, images from the event can be found on our Flickr photo set.

Previously: The brain whisperer: Stanford neurologist talks about his work, shares tips with aspiring doctorsAt Med School 101, teens learn that it’s “so cool to be a doctor” and Med School 101 kicks off on Stanford campus today

Events, Medicine and Literature, Medicine and Society, Stanford News

Stanford’s Medicine and the Muse symposium features author of “The Kite Runner”

Stanford's Medicine and the Muse symposium features author of "The Kite Runner"

Hosseini SmallNext Wednesday, Stanford’s annual Medicine and the Muse symposium will bring together medical student art, music, photography and literature in a series of performances and exhibits. During the event, Khaled Hosseini, MD, bestselling author of The Kite Runner, A Thousand Splendid Suns and And the Mountains Echoed, will join Paul Costello, chief communications officer for the School of Medicine, in conversation. He will also be available for book signing.

This year’s Medicine and the Muse theme is “Renewal,” informed by Hosseini’s writing. The event “is an opportunity for medical students to share their artistic talents, and to hear from a physician who has followed his muse to success in writing,” said Grace Xiong, a member of the medical student committee organizing the event.

Medicine and the Muse takes place April 16, from 5:30-8:30 PM in Berg Hall of the Li Ka Shing Center for Learning and Knowledge on the Stanford campus. The event is free and open to the public, but RSVPs are requested. To RSVP, e-mail mandm2014@lists.stanford.edu, or call 650-725-3448.

Photo by Elena Selbert

Autism, Medicine and Literature, Medicine and Society

“No, I’m not ready yet”: A sister’s translation for her brother with autism

Over on Medium.com, Abby Norman shares experiences from her youth in a family with a brother, Caleb, who has autism and a mother with an eating disorder. Able to observe and interpret Caleb’s ways of communicating, Abby acts as a translator to give him a voice that others will hear and, one hopes, understand.

From the piece:

What calmed him was lying on the bed for hours, motionless, watching the numbers of the digital clock change.

He did not potty train on schedule. Instead, he had somewhat of an intense penchant for smearing feces all over the rug and walls of the house. This was his way of saying, “No, I’m not ready yet.” … His relationship to the toilet had nothing to do with his bodily needs: the toilet was his method of rejecting objects. If he didn’t want something, he’d flush it down the toilet.

He was only aggressive in the sense that, when startled or overwhelmed, he would kick and scream. They started out seeming like normal tantrums; but while most kids could be consoled, Caleb could not be, and he would have to literally wear himself down before he would stop.

The author notes that even in understanding her brother’s differences, she was not necessarily his ideal caretaker. The piece continues:

Once he started school, the nightmare only intensified. I say that not to describe what life was like for us, but for him. School, with its unpredictable nature and constant social interaction, its lack of structure for kids who needed anything other than “normative learning.” The truth was, Caleb wasn’t really special needs. He was extremely intelligent.

At home, his day to day life was more or less consistent. While my experience growing up with a mum with an eating disorder was difficult, for Caleb, the obsessive-compulsive nature of her lifestyle was exactly what he required to stay calm and safe. He and my mother had, and to this day still have, a very symbiotic relationship.

Previously: Inspired by his autistic son, a Stanford researcher works to understand the biochemistry of autismThe Reason I Jump: Insights on autism and communication, A mother’s story on what she learned from her autistic son and Autism therapies: It still comes down to parents

Neuroscience, Patient Care, Stanford News, Videos

Treating intractible epilepsy

Treating intractible epilepsy

In this new Stanford Medicine video, patient Laura Koellstad tells the story of how her life changed with her first seizure and a diagnosis of intractible epilepsy, and then turned around following treatment at Stanford. Josef Parvizi, MD, PhD, associate professor of neurology and neurological sciences, and Robert Fisher, MD, PhD, director of the Stanford Comprehensive Epilepsy Program, explain the functional mapping and surgical procedures used to treat Koellstad’s condition, allowing her to return to work and regain her ability to drive.

Previously: The brain whisperer: Stanford neurologist talks about his work, shares tips with aspiring doctorsHow epilepsy patients are teaching Stanford scientists more about the brain and Implanting electrodes to treat epilepsy, better understand the brain

Cardiovascular Medicine, Nutrition, Science

What’s not to love? Chocolate’s feel-good chemicals

Cabdury2Spring is here and symbols of new life abound. If Cadbury Cream Eggs (yes, gross, but I love them anyway) and Mini Eggs on drugstore shelves have you, too, thinking about chocolate, check out this piece in the Washington Post on the history and chemistry of the “feel-good” components of the stuff, including “the world’s most widely consumed psychoactive drug,” caffeine.

Chemist Simon Cotton, PhD, writes:

Another chocolate molecule believed to be important was discovered less than 20 years ago: anandamide. This binds to receptors in the brain known as cannabinoid receptors. These receptors were originally found to be sensitive to the most important psychoactive molecule in cannabis, Δ9-THC. Likewise, anandamide and similar molecules found in chocolate are also thought to affect mood.

Phenylethylamine, another family of chemicals, is found in chocolate in very small amounts. It is a naturally occurring substance with a structure that is closely related to synthetic amphetamines, which of course, are also stimulants. It is often said that our brain produces phenylethylamine when we fall in love. It acts by producing endorphins, the brain’s natural “feel-good” molecules. The bad news, however, is that eating chocolate is probably not the best way of getting our hands on phenylethylamine as enzymes in our liver degrade it before it can reach the brain.

There are other molecules in chocolate – especially in dark chocolate – such as flavonoids, which some scientists think may help improve cardiovascular health. But chocolate manufacturers have been known to remove bitter flavanols from dark chocolate.

One last feel-good factor, which isn’t a molecule: the melt-in-your mouth sensation. The fatty triglycerides in cocoa butter can stack together in six different ways, each resulting in a different melting point. Only one of these forms has the right melting point of about 34 degrees, so that it “melts in your mouth, not in your hand.” Getting the chocolate to crystallize to give this form is the product of very careful chocolate engineering.

I’m curious to know what kinds of chemicals give the sugary “whites” and “yolks” of the cream eggs their appeal, though maybe it’s better kept a foil-wrapped secret.

Previously: When caffeine dependence affects quality of lifeDo you (heart) chocolate? Evaluating the cocoa “prescription” for cardiac health and Mapping the DNA of wild strawberries and fine chocolate
Photo by Joel Kramer

Clinical Trials, NIH, Nutrition, Obesity, Research, Stanford News

Stanford seeks participants for weight-loss study

Stanford seeks participants for weight-loss study

Should diets come in different shapes and sizes? Stanford researchers are exploring that question and are seeking participants for a year-long weight-loss study that aims to understand why people may respond differently to the same diet. Titled “One Diet Does Not Fit All,” the study will examine how factors such as genetic influences and eating and sleeping habits have an impact on a diet’s effectiveness.

From a release:

Participants will be assigned randomly to either a very low-fat or very low-carbohydrate diet for 12 months. They will be required to attend weekly classes at Stanford for the first three months, once every other week for the following three months, and once a month for the remainder of the study. Participants must also be willing to have fasting blood samples drawn four times during the 12-month period and participate in online and written surveys. They will receive all test results at the end of the study.

The study is part of a five-year project funded by the National Institutes of Health and the Nutrition Science Initiative. Following an enrollment last year of 200, this spring researchers hope to enroll at least 135 men and women (pre-menopausal only) between the ages of 18 and 50 who are overweight or obese and are generally in good health.

For a complete list of inclusion criteria, click here. To determine eligibility for this study, complete a brief online survey. For more information, contact Jennifer Robinson at nutrition@stanford.edu.

Previously: How physicians address obesity may affect patients’ success in losing weight, To meet weight loss goals, start exercise and healthy eating programs at the same time, The trouble with the current calorie-counting system, Smaller plates may not be helpful tools for dieters, study suggests and Losing vitamins – along with weight – on a diet

Grand Roundup

Grand Roundup: Top posts for week of March 30

The five most-read stories this week on Scope were:

Stanford bioengineer develops a 50-cent paper microscopeManu Prakash, PhD, assistant professor of bioengineering, has developed an ultra-low-cost paper microscope to aid disease diagnosis in developing regions. The device is further described in a technical paper.

Free DIY microscope kits to citizen scientists with inspiring project ideas: Through the Ten Thousand Microscope Project, Manu Prakash is giving away 10,000 build-your-own paper microscope kits to citizen scientists with the most inspiring ideas for how to use his new invention, called the Foldscope.

The brain whisperer: Stanford neurologist talks about his work, shares tips with aspiring doctors: Last week at Med School 101, neurologist Josef Parvizi, MD, PhD, shared with high-school students how he collaborated with musician Chris Chafe, PhD, on a “brain stethoscope” that can translate brainwaves into music.

Bad news for pill poppers? Little clear evidence for Vitamin D efficacy, says Stanford’s John Ioannidis: A large study of vitamin D led by John Ioannidis, MD, DSc, found that more well-designed studies and trials are necessary before firm conclusions can be drawn about its efficacy.

Double vision: How the brain creates a single view of the world: Carla Shatz, PhD, Stanford Bio-X director, has shown that a protein originally known for its role in the immune system, called MHC Class I D, or D for short, is present in the nerves of the developing brain.

And still going strong – the most popular post from the past:

The mystery surrounding lung-transplant survival rates: A 2012 article in the San Francisco Chronicle offered a look at the challenges facing lung transplant patients and explored why a significant number don’t live beyond the five-year mark, despite improvements in survival rates.

Behavioral Science, Nutrition, Obesity, Research, Women's Health

Obesity and smoking together may decrease taste of fat and sweet but increase consumption

puddingA study from Washington University School of Medicine in St. Louis and Philadelphia’s Monell Center has found that obese women who smoke cigarettes may have reduced sensitivity to the tastes of sweetness and fat in food and may be more likely to eat more calories.

Researchers engaged 47 female participants ages 21 to 41, grouped as follows: obese smokers, obese nonsmokers, normal-weight smokers, and normal-weight nonsmokers. All of the participants tasted vanilla puddings and were asked to rate the sweetness and creaminess of each one. The researchers found that the women who were obese and smokers rated less creaminess and sweetness in the puddings than the other three groups did.

From a release:

[Study author Yanina Pepino, PhD,] cautioned that the study only identified associations between smoking and taste rather than definitive reasons why obese smokers were less likely to detect fat and sweetness. But the findings imply that the ability to perceive fat and sweetness — and to derive pleasure from food — is compromised in female smokers who are obese, which could contribute to the consumption of more calories.

“Obese people often crave high-fat foods,” she said. “Our findings suggest that having this intense craving but not perceiving fat and sweetness in food may lead these women to eat more. Since smoking and obesity are risk factors for cardiovascular and metabolic diseases, the additional burden of craving more fats and sugars, while not fully tasting them, could be detrimental to health.”

The results were published in the journal Obesity.

Previously: Obesity is a disease – so now what?How eating motivated by pleasure affects the brain’s reward system and may fuel obesity and The brain’s control tower for pleasure
Photo by dutchfulthinking.blogspot.com

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