Bay Area native Cheri D. Mah, MD, MS has made a name for herself as the pioneer of bringing sleep medicine to professional athletes to enhance performance. Specifically, she is hired as a consultant to offer research-based sleep strategies for improved athletic achievement and help athletes beat jet lag while on the road.
Dr. Mah has worked in sleep research and consulting for more than 20 years and has racked up an impressive resume. She has worked with Formula One, military personnel, as well as gold-medalist swimmer and Stanford alumna Katie Ledecky for two Olympics. Dr. Mah has also worked with professional sports teams in the National Football League (NFL), National Basketball Association (NBA), National Hockey League, (NHL), and Major League Baseball (MLB), such as MLB’s San Francisco Giants for eight seasons and the NFL’s Philadelphia Eagles for multiple seasons.
“Applying sleep science with professional teams has been such a fun experience,” says Dr. Mah. “Working with the Giants, I developed a comprehensive sleep performance program for the players, staff, and organization. And, in 2017, I won a Super Bowl ring when I was working with the Philadelphia Eagles!”
Dr. Mah has also partnered with large athletic brands, such as Nike and Under Armour, to raise awareness about how sleep impacts athletic performance. She also collaborated with ESPN to produce the “Schedule Alert” project where Dr. Mah predicted when NBA teams were at highest risk of losing based strictly on their travel schedule. This prediction, aptly named the “Mah Score,” was based on a formula Dr. Mah created that considered many factors, such as direction of and amount of travel, recovery time, and potential for jet lag. For example, if a team from the West Coast was traveling after a night game to the East Coast after playing multiple consecutive games, Dr. Mah would predict that the West Coast team would be at risk of losing to an East Coast team that was better-rested and not jet lagged.
“I was nervous about this project because it could have been disappointing if the predictions were wrong, but in the end, they were 76 to 86 percent correct over three NBA seasons, which was very exciting,” says Dr. Mah.
The Power of Mentorship
As a rising freshman, Dr. Mah began conducting research with Dr. Wiliam Dement at Stanford, who is considered the founding father of the field of modern sleep medicine. Dr. Dement discovered the connection between dreaming and rapid eye movement, launched the first sleep clinic at Stanford, and started the popular course “Sleep and Dreams” in 1971, which is still offered today.
“The first sleep study I helped Dr. Dement with at Stanford, we were studying the effects of sleep extension in undergraduates. Several athletes were coincidentally in the study and I recognized that their athletic performance improved when they extended their sleep,” says Dr. Mah.
“Few others were studying sleep and athletic performance at that time. These early results were intriguing, and I was curious to understand more about interventions that could enhance sleep and performance. This ultimately set me on an unanticipated career path trajectory at the age of 17,” says Dr. Mah.
She continued working with Dr. Dement for the next 12 years throughout her undergraduate degree in biological sciences and psychology, master’s degree in biological sciences, and post-graduate years. Soon after earning her master’s degree, she launched her consulting business working as a sleep expert with athletes in the Bay Area.
“Dr. Dement had mentored everyone in the field of sleep medicine and I had the unique opportunity to be one of his last mentees during my years at Stanford in the early 2000s,” says Dr. Mah. “I’m so grateful for his mentorship. He has no doubt helped shape me to be where I am today.”
Medical Studies
After seven years conducting athlete studies at Stanford and working as a consultant, Dr. Mah returned to medical school at UC San Francisco and subsequently trained in Internal Medicine at Kaiser San Francisco. Unfortunately, the COVID-19 pandemic hit while she completed her three-year residency at Kaiser Permanente Hospital in San Francisco.
“I was a senior resident when COVID-19 struck the Bay Area, admitting patients from the emergency room,” says Dr. Mah. “It was a very scary time to be in medicine, trying to figure out how to manage this virus we didn’t have enough information about.”
In 2021, she returned to Stanford for a fellowship in Sleep Medicine and continued her consulting business with professional sports teams. Whether it was the pandemic or the pressure of being a professional athlete, Dr. Mah emphasized to her clients the importance of having a consistent wind-down routine to calm the nervous system before bed.
“When things are uncertain or hectic, having a consistent wind-down routine, based on evidence-based sleep strategies, is something you can trust to calm your brain and body,” says Dr. Mah. “When my clients or athletes have a bad game or another stressor comes up, I tell them their wind-down routine can serve as a foundation to fall back on, something their brain and body are familiar with to prepare them for sleep.”
Wearing Many Hats
Along with her consulting business, Dr. Mah also serves as a sleep expert for various Silicon Valley technology start-up companies, including those developing sleep technologies and wearables.
Also, to honor her mentor, Dr. Dement, Dr. Mah is an Adjunct Lecturer for the “Sleep and Dreams” course at Stanford. “Dr. Dement passed away a couple of years ago and we miss him,” says Dr. Mah. “I’m still close with his family, and his daughter opens the class every year by sharing about her father and continuing his legacy, which is a really special touch.”
Lastly, Dr. Mah is also a new mom. She currently lives in Sunnyvale, California with her husband and 17-month-old son. “I know how essential sleep is and try to make healthy sleep practices a priority, but kids can be a wild card,” says Dr. Mah.
“I did not get the best sleep as a new mom this past year, but it is all about the small changes we can do to improve the sleep we get each day. Start with one change to get better sleep tonight to help you be your best tomorrow,” says Dr. Mah.
By Nicole Molumphy
Do you ever get those late-night cravings or feel like your hunger is never satiated? Research shows that consistent short sleep duration (less than 7 hours per night) can influence metabolic health, affect the function of appetite hormones, increase food cravings, and lead to a 38 percent increase in obesity in adults.
Consistent sleep deprivation can lead to altered functioning of the appetite hormones ghrelin and leptin. Ghrelin increases our appetite and is released by cells in the stomach lining. When your stomach is “growling,” that is the ghrelin hormone talking. Conversely, the hormone leptin, made by our fat cells, lowers our appetite. Studies have revealed that sleep deprivation can lead to increased ghrelin and decreased leptin, resulting in an overall experience of constantly being hungry.
“There are so many health conditions associated with poor sleep,” says Rob Oh, MD, Clinical Associate Professor (Affiliated) and family physician at the Veterans Affairs Health Care System in Palo Alto. “With chronic sleep deprivation, your metabolism becomes dysregulated, leading to cravings for processed foods. Also, you’re less likely to exercise, you feel more stressed, and you’re more likely to think poorly. The combination of these factors can lead to metabolic health problems like obesity and type 2 diabetes.”
Sleep Deprivation Increases Stress Hormones
Our cortisol levels are typically lowest near midnight and then increase towards waking hours, ultimately peaking around 9 a.m. Studies demonstrate that reoccurring poor sleep is associated with an altered cortisol secretion pattern.
For example, delaying your bedtime could lead to high cortisol levels in the middle of the day, rather than just in the morning. Sustained high levels of cortisol can lead to an increased amount of insulin in the blood, which promotes the accumulation of belly fat and has the potential to lead to prediabetes, type 2 diabetes, and other metabolic disorders. An increase in cortisol levels during the day may induce prolonged feelings of stress, increased food cravings, and further insomnia—promoting a recurrent, cyclical pattern.
“Inadequate sleep disrupts hormone levels, which dysregulates one’s metabolism and makes individuals hungrier,” says Dr. Oh. ” When we are hungrier, we eat more, which leads to weight gain and potentially metabolic disease.”
If that’s not bad enough, cravings for ultra-processed foods, sugars, and alcohol become more of a tease with sleep deprivation. A possible mechanism for this added hunger is an increased activation of the endocannabinoid system, which is found throughout the body and controls several biological systems, including sleep, mood, and appetite.
Sleep Deprivation and Increased Risk of Diabetes
Research shows that a lack of sleep may also result in insulin resistance, a driving factor in prediabetes and type 2 diabetes. Insulin is a hormone made by the pancreas that regulates blood glucose levels. Insulin resistance occurs when cells in the liver, fat, and muscles do not respond well to insulin, and in turn, glucose is not taken up into the blood.
The exact mechanism behind the causal relationship between insufficient sleep and insulin resistance is still being studied, however, some studies note that increased inflammatory markers, like C-reactive protein and hormone dysregulation, such as cortisol may be involved.
Currently, prediabetes affects one in three adults in the US. While many mechanisms contribute to the development of prediabetes and type 2 diabetes, some of the more prominent ones include impaired cellular insulin sensitivity, modified gut microbiota, and overly-sensitive sympathetic nervous system (fight-or-flight) activation. When the sympathetic nervous system is activated, it signals the liver to release more glucose into the bloodstream, leading to higher blood sugar levels.
What Can We Do About It?
Unfortunately, research finds that “weekend recovery sleep” is not enough to bring your metabolism back into balance after a lack of sufficient sleep throughout the week. Instead, Dr. Oh recommends taking a holistic approach and examining not only your sleep habits but also your nutritional choices and workout routines to support the restoration of metabolic health.
For those with pre-diabetes and type 2 diabetes, a diet focused on whole foods and low refined carbohydrates is critical for weight loss and glucose control.
Specifically, Dr. Oh recommends a low carbohydrate diet, such as consuming 75 to 100 grams of carbohydrates per day, to control and balance blood sugar levels. He also recommends quick, 20-minute, high intensity workouts for time-efficient and effective exercises that promote metabolic health. Regarding supplements, Dr. Oh recommends magnesium to promote muscle recovery and relaxation before bedtime.
“Optimal sleep is so intertwined with athletic and exercise performance, brain health, and metabolic health,” says Dr. Oh. “Sleep really is a keystone area where many of us can do better and hence reducing our risk for metabolic diseases and lengthening our healthspan.”
By Angel Cleare, BS and Sharon Brock, MS
From Oura Rings to Fitbits, wearable sleep-tracking devices are all the rage in today’s technology-driven world. In 2020, almost 30 percent of US adults used wearable healthcare devices. But rather than running out to buy one, we must first ask ourselves, “Do these wearables live up to the hype?” We sat down with a Stanford sleep expert to find out.
“Sleep wearables can be helpful tools to provide insights on your sleep trends over weeks to months. However, if you find that the wearable causes you anxiety when you view the sleep data or becomes an obsession to perfect the daily sleep stats, it may be no longer a helpful tool for your sleep health,” says Cheri Mah, MD, MS, sleep physician and Adjunct Lecturer at the Stanford Sleep Medicine Center.
As Dr. Mah alluded, the quest for perfect sleep data on one’s wearable can ironically lead to restless nights. This preoccupation with perfecting one’s sleep is a condition known as orthosomnia. Instead of winding down in preparation for sleep, people with orthosomnia may feel anxious about achieving the “perfect” sleep data the following morning—an anxiety that can keep them up at night.
“If you find viewing the daily sleep wearable data is causing you unhealthy stress or anxiety, it may be time to consider making a change. Consider switching to only viewing the wearable data on a weekly basis to note weekly trends, take a break from using the wearable, or if you still want to track your sleep patterns, switch to using a pen and paper sleep journal,” says Dr. Mah.
It’s also important to note that the data sleep wearables provide is not always accurate, so we may be feeling anxiety over inaccurate data. Dr. Mah says that although wearables provide reliable estimates of sleep duration, bedtime and wake time, and sleep schedules, research shows there are limitations with accuracy and reliability regarding data on specific sleep stages, such as amount of REM and deep sleep.
Who Should Wear Sleep Wearables and Who Should Not?
Dr. Mah works with professional athletes, sports teams, and other high performing professionals. She has found sleep wearables to be helpful to better understand their sleep patterns, make changes to improve their sleep habits, and ultimately improve athletic performance and health.
“For athletes and other high performers, wearables can be useful tools for establishing how their current sleep trends are, monitoring and optimizing sleep throughout their season, and ultimately, impacting on-field performance,” says Dr. Mah.
Conversely, Dr. Mah says those who struggle with sleep should be cautious of using a wearable and wearables are not intended to diagnose sleep disorders. Many wearables include motion-based sensors and therefore the sleep data can be misleading if someone has difficulty falling asleep or staying asleep. This can impact the wearable’s estimate for amount of time to fall asleep, awakenings at night, and the total sleep duration.
If you struggle with sleep, have insomnia, or have concerns about a clinical sleep disorder such as sleep apnea, Dr. Mah recommends reaching out to a primary care physician or a sleep physician.
“As technology continues to improve, the accuracy and reliability of sleep wearables will hopefully continue to get better. I anticipate that sleep wearables will become even more helpful for clinicians because they provide a longer snapshot of one’s sleep patterns than we wouldn’t otherwise have access to,” says Dr. Mah.
For those who want to track their sleep in another way, Dr. Mah recommends using a pen and paper sleep journal rather than a wearable. “You don’t have to use a wearable to gain insights about your sleep. A pen and paper sleep journal can be incredibly helpful, too,” she says.
Millions of Americans share a similar experience every morning. The alarm goes off, but they’ve already been awake for hours in bed. They hit the snooze button to squeeze in a few more minutes of precious rest, not realizing they were making their sleep problems worse.
“Hitting the snooze button is one of the worst things you can do because it prolongs morning grogginess and associates the bed with being awake,” says Fiona Barwick, PhD, DBSM, Stanford Clinical Associate Professor, Psychiatry and Behavioral Sciences – Sleep Medicine. “Rather than hitting snooze, it’s important to get out of bed within 15 minutes of the alarm going off and get some natural light to stop melatonin production.”
You may not think that something you do first thing in the morning will affect your sleep that night; however, Dr. Barwick says that the behaviors we engage with throughout the day can impact the quality of our sleep at night.
“Getting a good night’s sleep is a 24-hour endeavor,” says Dr. Barwick.
How Does Sleep Work?
According to Dr. Barwick, we fall asleep when these three biological systems are in working order:
- Circadian Rhythm (CR)
- Sleep Drive (SD)
- Stress Management (SM)
Here is a list of behaviors that can negatively affect the three systems (CR, SD, SM), as well as alternative behaviors that have a more positive impact:
Since it may be difficult to change all the behaviors in this table, Dr. Barwick shares the top two behaviors that are most important for each system:
- Circadian Rhythm
- Sleeping in the right window for your body clock (e.g., 10pm – 6am, 11pm – 7am, or 12am – 8am, etc.) and staying consistent with those sleep and wake times.
- Appropriate exposure to light and darkness to sync the release of melatonin with wake and sleep times (e.g., getting morning sunlight, not looking at screens one hour before bed, and making sure the bedroom is dark).
- Sleep Drive
- Increase sleep drive by tiring the body with regular physical exercise and outdoor light exposure.
- Getting out of bed promptly (no hitting the snooze button) and making sure you spend the appropriate amount of time in bed (anywhere from 6-10 hours depending on your individual genetics and age).
- Stress Management
- Physical relaxation—Deep breathing throughout the day to relax the body.
- Mental/Emotional relaxation—mindfulness meditation or journaling to process emotions before going to bed.
Practice of the Month:
Avoid hitting snooze (i.e., get out of bed when the alarm goes off) and create morning, midday, and evening routines to optimize the three key systems for sleep.
From the table above, write two behaviors you can do in the morning, midday, and at night. Make sure that you’re addressing all three systems (CR, SD, and SM).
What to do in the morning for good sleep:
1)
2)
What to do during the day for good sleep:
1)
2)
What to do at night for good sleep:
1)
2)
Here is a sample:
What to do in the morning for good sleep:
1) Put phone out of arm’s reach and get out of bed right after alarm goes off (CR, SD).
2) Go for a walk around the block, then eat breakfast (CR, SD).
What to do during the day for good sleep:
1) Stress reduction: do a 10-minute mindfulness meditation at lunch (SM).
2) Physical exercise: do a 45-minute workout right after work (SD, SM).
What to do at night for good sleep:
1) Turn off all screens one hour before bed and write in my journal while listening to relaxing music (CR, SM).
2) Take a luxurious candle-lit bubble bath while taking deep breaths and counting my blessings (CR, SM).
“These are behaviors we can do to increase the likelihood of getting better sleep, but there may be times when we do everything right and still not sleep well,” says Dr. Barwick. “The most important thing to remember is that we will be fine the next day. We are evolutionarily adapted to deal with insufficient sleep, and we can still do what we need to get done, even without the full amount of sleep that we normally get.”