Tag Archive for: brain health

By Sharon Brock, MEd, MS

Stanford psychiatrist Douglas Noordsy, MD, is a physician who literally walks his talk. For the last 40 years, he has woken up at 6 a.m., drank a glass of water, and gone for a run, often with his dog.

“Living a healthy lifestyle has always been an integral part of my life. I share lifestyle interventions [such as daily exercise] with my patients because these practices have worked for me,” says Dr. Noordsy, Head of the Stanford Lifestyle Medicine Cognitive Enhancement pillar.

As a practicing psychiatrist for more than 35 years, editor of the book Lifestyle Psychiatry, and founder of the Stanford Lifestyle Psychiatry Clinic, Dr. Noordsy has played an integral role in incorporating lifestyle medicine into traditional psychiatry care. Dr. Noordsy’s research interests at Stanford include medication and the impact of exercise and nutrition for individuals with schizophrenia and bipolar disorder. He is currently Director of the Lifestyle & Sports Psychiatry special initiative in the Department of Psychiatry.

“With lifestyle psychiatry, clinicians utilize three methods of care—psychotherapy, medication, and lifestyle interventions,” he says. “This three-pronged approach helps us to be more effective physicians, and patients have a better chance at achieving their best outcomes.”

Northeastern Roots

Doug Noordsy always knew he wanted to be a physician. Initially thinking he would go into primary care, he shadowed his family’s doctor as a high school student in Syracuse, New York. As an undergraduate, he took pre-med courses at St. Lawrence University, a small liberal arts college in upstate New York.

“In my junior year, I took the ‘Introduction to Psychology’ course and I fell in love with it,” he says. “I was particularly interested in those with significant disorders such as schizophrenia—I was intrigued by how they thought. So those early experiences drew me into psychiatry.”

In the 1980s, he attended medical school at Washington University in St. Louis, Missouri. During this time, neuroscience and psychopharmacology were becoming more advanced, which led to debate among mental healthcare professionals about the relative merits of pharmaceuticals over psychotherapy.

“We learned about psychotherapy and medication, but lifestyle medicine wasn’t on the table at that time,” says Dr. Noordsy. “There was discussion about the importance of social support, but we didn’t consider how other aspects of lifestyle affected mental health, such as exercise, nutrition, and mind-body practices.”

After completing his residency at Dartmouth-Hitchcock Medical Center in New Hampshire, he served as a Professor of Psychiatry at the Geisel School of Medicine for 25 years. At Dartmouth, he was also the Director of Psychosis Services and an Investigator in the Psychopharmacology Research Group.

“At Dartmouth, there was an emphasis on treating patients in a collaborative, recovery-oriented way rather than a paternalistic approach,” says Dr. Noordsy. “It was important in my early development to be trained in a model of care that was respectful of the wishes and preferences of the patient.”

Leading a Movement

Dr. Noordsy was ahead of his time regarding the connection between lifestyle medicine and mental health. As a medical school student, he managed his own mental health using lifestyle practices such as daily exercise, healthful nutrition, and quality sleep. He found benefit with these practices and shared them with his patients.

“At first, I was shy about sharing my experiences because they weren’t evidence-based at that time. It’s counter-academic to share things with patients from your own life that are not supported by clinical trials,” he says. “But over time, the evidence caught up.”

Indeed, over the last 15 years, research on lifestyle medicine has shifted the narrative from personal anecdotes to gaining attention and respect within the medical community. Specifically, Lifestyle Psychiatry has moved from something psychiatrists recommended softly to valid, evidence-based medicine.

In the fall of 2015, Dr. Noordsy came to Stanford to join the Department of Psychiatry & Behavioral Sciences, which was building a team for student-athletes. Many of the athletes wanted to minimize medication exposure, so he continued to recommend lifestyle interventions as options to support their mental health.

In 2019, Dr. Noordsy coined the term “Lifestyle Psychiatry” by publishing a book with that title. This book is a curation of research from around the world detailing the evidence on lifestyle practices in psychiatry. In 2020, he opened the Stanford Lifestyle Psychiatry Clinic. In 2024, the president of the American Psychiatric Association (APA) promoted lifestyle interventions as a core component of psychiatric treatment, bringing this approach into the mainstream.

In his 35-year career, Dr. Noordsy has been a member of the Schizophrenia International Research Society, the International Early Psychosis Association, the American College of Lifestyle Medicine, and a fellow of the APA. He received the Exemplary Psychiatrist Award from the National Alliance on Mental Illness in 2001 and the Excellence in Leadership Award from the Stanford Department of Psychiatry and Behavioral Sciences in 2018.

Although Dr. Noordsy is a nationally acclaimed psychiatrist, his most significant source of pride is his influence on how psychiatric care is delivered. For severe disorders, psychiatry has had a long history of authoritarian care in some settings. With lifestyle psychiatry, where patients choose from a menu of lifestyle practices as part of their treatment plan, the care model shifts from “the doctor knows all” to one where the psychiatrist collaborates with their patients, respects their wishes, and takes a whole-person approach.

“What I’m most proud of is being part of a movement toward empowering and engaging patients to participate in their own health and well-being, rather than just be compliant to their doctor’s instructions,” says Dr. Noordsy. “I’m proud to be part of a new approach to care that promotes mental health by fostering relationships, savoring nutritious meals, and experiencing the beauty of nature at sunrise.”

By Tanya Thakur, MBBS

Alzheimer’s disease (AD) is one of the most devastating illnesses among older adults. The disease not only degrades memories but also affects one’s independence and takes a toll on family members.

AD is a progressive neurodegenerative disorder caused by the accumulation of abnormal misfolded protein deposits in the brain, including beta-amyloid plaques, tau tangles, and Hirano bodies. These deposits disrupt normal neuronal function, leading to the gradual loss of memory, cognitive skills, and, eventually, the ability to carry out daily activities.

AD is the most common cause of dementia, accounting for approximately 60 to 80 percent of cases. Presently, an estimated 6.7 million individuals in the U.S. have AD. In 2019, Alzheimer’s was ranked as the sixth leading cause of mortality among individuals aged 65 and above. Notably, between 2000 and 2019, while fatalities from stroke, heart disease, and HIV declined, deaths related to Alzheimer’s increased by more than 140 percent.

Even though scientists are working toward curing AD, we can take preventative measures by incorporating healthy habits, such as regular exercise, into our routine.

“It is a common misconception that we have minimal control over our risk of developing Alzheimer’s disease. However, nearly half of the Alzheimer’s cases could have been prevented or delayed by modifiable factors, including lifestyle changes,” says Sarita Khemani, MD, Clinical Associate Professor of Medicine and Neurosurgery Hospitalist at Stanford University. “Therefore, we should do everything in our power to incorporate healthy lifestyle habits as early as possible.”

The Link Between Exercise and Alzheimer’s Disease

There are many things we can do to reduce our risk of developing dementia. Several research studies have concluded that physical activity is one of the best ways to reduce risk significantly. For example, after analyzing 16 studies on exercise and dementia, the Alzheimer’s Society found that regular exercise reduces the risk of developing dementia by 28 percent and, specifically, AD by 45 percent.

The connection between the brain and aerobic exercise is likely due to neuroplasticity, which is the brain’s ability to adapt and form new neural connections or strengthen the existing ones. During aerobic exercise, our brain expresses cAMP response element binding (CREB) proteins that influence the transcription of synaptic genes, including those encoding for brain-derived neurotrophic factor (BDNF). BDNF supports neurogenesis (the formation of new neuron cells), neuroprotection, and angiogenesis (the formation of new blood vessels). BDNF also increases the volume of gray matter and the hippocampus (the site of memory in the brain).

Physical activity also serves as a potent modulator of other health risk factors, including hypertension, hypercholesterolemia, and insulin resistance, all of which increase the risk of developing dementia. Vascular damage caused by atherosclerosis can accelerate the cognitive decline associated with AD due to reduced blood and oxygen flow to the brain, leading to hypoxia of neural cells.

“Brain changes associated with Alzheimer’s begin approximately 20 years before symptoms appear,” says Dr. Khemani. “Exercise stands out as one of the most effective strategies for prevention, offering a low-cost, non-pharmacological, and low-risk option accessible to everyone.”

The Best Exercises to Prevent Alzheimer’s

While aerobic exercise increases BDNF levels, resistance exercises, such as lifting weights, are thought to have a greater influence on insulin-like growth factor-1 (IGF-1) levels. IGF-1 is a hormone that manages the effects of growth hormone in the body and is essential for promoting cognitive abilities.

Because aerobic and resistance exercises elicit different neurophysiological changes, studies have indicated that combining both modalities can enhance exercise-induced neuroplasticity to a greater extent than either modality alone.

For example, one study compared the effects of combined aerobic and strength training, aerobic exercise alone, and no exercise on cognitive function among dementia patients. After nine weeks, the combined exercise regimen yielded the most pronounced results across cognitive domains. Also, the observed gains in both motor and cognitive areas regressed towards baseline levels more than two months post-intervention, meaning it is essential to exercise regularly to sustain its neurological benefits.

Regarding the type of aerobic exercise most effective for AD prevention, Dr. Khemani recommends incorporating sprint intervals into our workouts. “We encourage our patients to engage in moderate-intensity exercises incorporating some high-intensity interval training, if possible, as these activities have been shown to be more impactful for Alzheimer’s prevention than light exercise alone,” she says.

 

By Maya Shetty, BS


Key Takeaways

  • Research shows that cold water immersion (CWI) may improve mental health by increasing endorphin and norepinephrine levels. 
  • CWI may also improve resilience to stress by decreasing cortisol levels.
  • CWI can be adapted to meet different wellness goals, whether for immediate relief or long-term mental health benefits.
    • For individuals seeking a quick boost in mood, daily cold water face immersions and occasional full-body plunges might be beneficial.
    • For those aiming for long-lasting benefits such as lowered cortisol levels, enhanced mood regulation, and increased resilience to stress, research shows that consistent full-body CWI may be beneficial.

Have you ever considered how taking a cold plunge might affect your mental state? Beyond the initial shock, CWI is proving to have profound effects on brain health and mental well-being. Initially popular as a recovery technique among athletes, it has now evolved into a bold wellness practice for those seeking to enhance their overall health. This practice, which involves plunging into cold water (roughly 10-15°C, 50-60°F), has ignited significant research interest, and emerging studies now suggest that CWI can improve mood, decrease stress, and potentially slow the progression of neurodegenerative diseases.

“I personally do cold water immersion and find it to be an immensely rejuvenating activity,” says Stanford Psychiatrist, Vanika Chawla, MD, member of the Lifestyle Medicine Cognitive Enhancement pillar.

CWI can take many forms, each involving its own protocol and equipment. The most common forms include:

  • Ice Baths: Traditionally utilized by athletes for recovery after intense physical activity, ice baths require submerging the body up to the neck in ice-cold water. Also known as cold plunging, this practice generally lasts only a few minutes and involves limited movement.
  • Cold Showers: A more accessible form of CWI, taking cold showers can offer many of the same benefits as ice baths but are easier to incorporate into daily routines.
  • Open Water Swimming: This active form of CWI involves swimming in cold rivers, lakes, or oceans, allowing for longer exposure times to the cold.
  • Cryotherapy Chambers: Though they do not involve water, cryotherapy chambers expose the body to extremely cold air temperatures for brief periods, stimulating a physiological response similar to that achieved through water immersion.

Choosing the type, temperature, and duration of CWI depends on your cold tolerance and the resources available to you. It is generally recommended to aim for a temperature that feels uncomfortable but still safe (no colder than 10°C, 50°F). If you have any form of access to cold water, whether it be a lake, a river, or your home shower and bathtub, you can participate in CWI and begin to explore its benefits.

Can Cold Water Plunges Improve Mental Health?

While the idea of diving into extremely  cold water seems unappealing to most, recent studies have shown that CWI offers emotional benefits. In 2021, researchers recruited undergraduate students to take a 20-minute dip in chilly sea water (13.6°C, 56.5°F) and report their emotions before and after using a Profile of Mood States questionnaire. Compared to controls, the students who engaged in CWI experienced a shift in mood, noting a significant decrease in negative emotions like tension, anger, depression, fatigue, and confusion. Moreover, they experienced boosts in positive emotions such as vigor and self-esteem. Further research involving thirty-three adults new to cold-water swimming highlighted similar benefits. After immersing in a cold bath (20°C, 68°F) for just five minutes, participants reported feeling more active, alert, attentive, proud, and inspired.

These studies, which utilize self-reported questionnaires, indicate that cold-water immersion may significantly enhance mood and overall psychological well-being. It appears to activate traits associated with increased motivation and vitality, while simultaneously diminishing feelings of distress and nervousness. 

How to Lower Cortisol Levels Naturally

CWI presents a unique stimulus for the body, prompting significant shifts in its hormonal stress response, particularly involving cortisol, a key regulator of stress. Unlike other stress hormones such as noradrenaline, cortisol levels remain relatively unchanged during the initial shock of cold water. Research highlights an intriguing aspect of cortisol dynamics: while levels do not significantly change during CWI, they significantly decrease afterward.

For example, a study concluded that a one-hour CWI session, whether in thermoneutral (32°C, 90°F), cooler (20°C, 68°F), or cold (14°C, 57°F) water, did not lead to an increase in blood cortisol concentrations. Instead, cortisol levels tended to decrease across all temperatures tested and remained below initial levels an hour after immersion. These findings suggest that cortisol production is not significantly activated by CWI, contrary to what might be expected under typical stress conditions. In fact, CWI may have potent stress-modulating effects. Further research indicates that cortisol levels remain considerably lower for up to three hours after just 15 minutes of CWI (10°C, 50°F). This pattern of response reveals a sophisticated regulatory mechanism, suggesting that CWI can effectively diminish feelings of stress following a session.

CWI may have the potential to modify our body’s stress response to stressors in everyday life. In a study where participants engaged in winter swimming (water 0-2°C, 32-36°F) for twenty seconds or cryotherapy (-110°C, -166°F) for two minutes, three times a week for twelve weeks, the body adapted remarkably. After just four weeks, participants showed significantly lower cortisol levels post-exposure, with levels continuing to drop in the following weeks. This adaptation contrasted with the noradrenaline response, which remained consistent even as the body became accustomed to the cold stress. This reduced cortisol response not only diminished the stress perceived from cold but also potentially enhanced the body’s capacity to manage other stressors more effectively. 

The main take away from this study is that by reducing cortisol production in response to repeated cold exposure, participants might also release less cortisol in response to other stressors in everyday life, thus fostering a more resilient physiological state over time.

“Resilience is the ability to adapt to life’s stressors and adversities,” says Dr. Chawla. “The body and mind are interconnected, therefore greater physiological resilience may lead to greater psychological resilience as well.”

How Cold Water Immersion Impacts the Brain

CWI has been scientifically observed to influence brain function, affecting mood, stress response, and potentially brain health through several mechanisms. The immediate physiological response triggered by CWI is largely due to the dramatic change in temperature. A dense concentration of cold receptors in the skin detects this change, leading to a surge of electrical impulses from peripheral nerve endings to the brain. This intense stimulation activates various neural pathways, initiating a cascade of chemical responses designed to help the body manage and adapt to the stressor.

During the initial shock of CWI, the body experiences stress and discomfort due to the sudden drop in temperature. To counteract this, endorphins, the body’s natural pain relievers, are released. These endorphins not only reduce pain but also enhance feelings of well-being, akin to the “runner’s high” that often occurs in other physically demanding or stressful situations. 

CWI also activates the sympathetic nervous system (SNS), which controls our “fight-or-flight” responses. This activation leads to a significant increase in noradrenaline (also known as norepinephrine), an excitatory neurotransmitter that not only helps manage stress but also boosts energy and focus. The surge in noradrenaline increases blood flow to the brain, potentially causing feelings of euphoria.

These two neurotransmitters play complementary roles. While norepinephrine prepares the body to handle acute stress by enhancing alertness and readiness, endorphins work to soothe pain and promote a positive mood. This dual response helps individuals cope with the immediate impacts of cold exposure more comfortably and can make the experience of cold water immersion more tolerable–and potentially even rewarding.

Regarding whether CWI has long-term positive effects on the brain, research indicates inconsistent results with respect to the increase of endorphin levels. It is possible that not everyone experiences this endorphin response to CWI, and among those who do, the effect may diminish over time, as the body becomes accustomed to the cold exposure. On the contrary, the increase in noradrenaline continues with each session of CWI, even after the body has adapted after months of regular practice. 

These findings underscore the potential of CWI to be used as a reliable tool for improving energy, focus, and mood. These findings also point to the potential of CWI to be used in the treatment of neurological conditions that involve low noradrenaline, including anxiety and depression. However, more research is needed to understand if CWI has long-term effects on emotional well-being outside the water.

Also, CWI may improve brain function through the release of cold-shock proteins, which are produced by the body in response to cold conditions. Animal studies reveal that proteins like RNA binding protein (RBM3) play a crucial role in repairing and regenerating nerve cell connections after they’ve been exposed to cold. Additionally, studies have demonstrated that over-expressing RBM3 can help prevent neuronal connection loss in mice with neurodegenerative diseases. Although there is limited evidence in humans, these findings in mice suggest that regular CWI could potentially boost the expression of such beneficial proteins in humans, offering protection against or slowing the progression of neurodegenerative diseases by preserving and reinforcing neural connections. 

Reaction to Cold Water: Full-Body vs. Facial Immersion

Physiological responses to CWI differ significantly based on whether the exposure is to the full body or just the face. Full-body immersion exposes a significant surface area to cold, inducing thermal stress that can substantially lower skin and core body temperatures. This extensive exposure activates the sympathetic nervous system, which in turn triggers a release of neurotransmitters and hormones that drive the stress response. Consequently, this leads to vasoconstriction, an increased heart rate, and a heightened metabolic rate, all of which help preserve body heat and maintain core temperature.

In contrast, immersing just the face in cold water activates parasympathetic activity, which is responsible for “rest and digest” functions in the body. This effect is likely due to the mammalian diving reflex—an evolutionary adaptation that optimizes respiration and conserves oxygen by preferentially directing oxygen to vital organs. The diving reflex is mediated by the vagus nerve, which activates the parasympathetic system and releases a sense of calm. The trigeminal nerve in the face also plays a crucial role when stimulated by cold, sending signals that further enhance parasympathetic output, decreasing heart rate, and boosting digestive activity. 

These differences highlight how CWI can be strategically used to target specific physiological responses and therapeutic outcomes, depending on whether the exposure is localized to the face or involves the entire body.

“I sometimes recommend facial cold water immersion to my patients as part of the T in TIPP skills to help people with emotion regulation. TIPP stands for temperature, intense exercise, progressive muscle relaxation, and paced breathing,” says Dr. Chawla. “These skills involve changing your body chemistry to shift emotions. Some people find brief facial immersion in cold water or taking a cold shower to be helpful in shifting their body chemistry and thereby shifting their emotional state.” 

Safety Considerations

CWI can offer several health benefits, but it’s essential to approach this practice with caution due to potential risks. One of the most obvious risks is hypothermia, as immersing in cold water significantly drops body temperature. To prevent hypothermia, limit immersion time to no more than 10 minutes

Furthermore, it is important to understand the cold shock response. Entering cold water suddenly can trigger an involuntary gasp reflex followed by hyperventilation. Hyperventilation increases the risk of drowning (especially in open water plunging) and can also lead to arrhythmias or even a heart attack, particularly in those with underlying heart issues. To better manage the cold shock response, it’s advised to enter the water slowly, allowing your body to adjust to the temperature gradually. 

It is also important to never swim alone regardless of your swimming strength or experience. Having a partner ensures that help is readily available in case of an emergency, such as cramps, sudden illness, or difficulty in the water.

Finally, remember to allow your body to gradually acclimatize to whatever CWI technique you choose. If you are a beginner, begin with shorter durations (2 minutes) in warmer water (roughly 20°C, 68°F), progressively moving to colder temperatures with longer durations as your body adapts.

“This intervention is not for everyone. It’s important for people to consider what works best for their individual needs,” says Chawla. “If you are going to try CWI, be mindful of how it impacts your mind and body and incorporate the activity into your routine accordingly.”

By Matthew Kaufman, MD

This blog is part of our Supplements newsletter. If you like this content, sign up to receive our monthly newsletter!


Key Takeaways:

Here are a few supplements that our health professionals recommend for healthy aging for individuals in midlife and beyond:

  • Creatine – To maintain and build muscle mass and potentially improve cognitive performance.
  • Vitamin D – To promote muscle and bone strength. 
  • Magnesium – To promote restful sleep and brain health.
  • B12 and B9 (folate) – To promote brain health. (B12 is particularly recommended for vegans since it is primarily found in animal products).
  • Multivitamin that is FDA-regulated or third-party tested. Unregulated supplements may not contain the active ingredients to live up to their advertised claims and may contain harmful ingredients.

As we age, taking too many supplements may be taxing to our liver and kidneys, so it’s best to screen to assess where we are deficient and supplement as needed.

Lifestyle choices are most important for maintaining good health as we age, and supplements do not replace a healthy diet and daily exercise.


As a Physical Medicine and Rehabilitation resident, my patients often ask me, “What supplements should I take as I get older?” While it is a complicated question without a clear answer, it’s important to consider. 

Rather than investigating how a supplement affects the entire body as we age, researchers study how supplements impact specific aspects of health, such as sleep, muscle mass, and brain health. However, we all know that we don’t age in only one domain–the aging process affects many parts of the body. Therefore, there are multiple supplements to consider, and which supplement you take depends on your individual goals.

So, whenever I am posed with this question, I always respond with these two questions: 

1) What are your goals regarding aging? Is it just a longer lifespan, or do you also want to feel good in your 70s and 80s and maintain high-quality interactions with people and places? 

2) What aging concerns do you want to address or avoid? Some examples include optimizing your bones and muscles for sustained athletic ability, brain health and cognition performance, and your ability to have restful sleep on a consistent basis.

Which Supplements Should I Take for Healthy Aging?

Supplements to Maintain Muscle Mass and Bone Strength

As we age, the most important things we can do to maintain muscle and bone strength are resistance training at least twice weekly and consume adequate protein, especially from food (both plant and animal sources). Without these two things in place, supplements alone have not been shown to be helpful. 

Regarding protein, I recommend consuming 1.2 – 1.6 grams per kg of body weight per day. This translates to approximately 0.65 grams of protein multiplied by your body weight in pounds, to be consumed evenly over three to four meals per day. 

To maintain and build muscle mass as we age, I also recommend creatine. Consuming between 5 – 25 grams of creatine per day (either as a supplement or in food) has been shown to increase strength and muscle protein synthesis, and maintain lean body mass.

Vitamin D supplementation also has substantial evidence showing improvements in muscle and bone strength in older adults.

Supplements for Brain Health and Cognitive Performance

Some studies show that vitamin D may improve brain health and cognitive performance. Also, magnesium and higher doses of creatine have emerging evidence suggesting they could also be helpful. B vitamins like B6, B12, and B9 (folate) have also been shown to help with cognition prior to diagnosis of mild cognitive impairment and Alzheimer’s Disease.

Many people take omega-3 supplements intending to improve cognition; however, the data is not as strong as many people suspect. Some studies suggest that these supplements are effective, and some don’t. Most experts believe that getting omega-3s from food (such as fatty fish, walnuts, and chia seeds) is preferable to getting them from a supplement in that they are better absorbed in the body. For my patients, I recommend consuming omega-3s by eating more salmon and enjoying a low-inflammatory diet, such as the Mediterranean diet.

Supplements for Sleep

There is not currently a supplement that the American Academy of Sleep would recommend, however, melatonin is the most popular sleep supplement. If you find melatonin helpful, it’s important to use it at the minimum effective dose to prevent circadian rhythm shifts. There is also recent evidence that magnesium is helpful for sleep.

Lifespan vs. Healthspan

 Lifespan is the number of years we are alive, whereas healthspan is how many of those years we feel good (physically and mentally) and are healthy enough to live independently and free from debilitating diseases. 

Although there is no magic pill for a longer life, these supplements may improve your healthspan by increasing your levels of functioning and slowing the progression of chronic conditions. Healthy aging is not only about preventing illness or falls; it also encompasses the ability to engage in activities we enjoy, spend quality time with people we love, and maintain a sense of purpose and excitement as an older adult. 

When choosing a supplement, it is crucial to remember that the FDA does not regulate most supplements. Therefore, there is minimal oversight regarding the ingredients in these supplements and whether they live up to their advertised claims. Without regulation, some supplements don’t contain the active ingredient, and they may even contain ingredients that are harmful, such as heavy metals, not listed on the bottle. Therefore, it is essential to go with supplements that are third-party tested or recommended by health professionals you trust and not just rely on advertising.  

Lastly, it is most important to recognize that supplements cannot replace a poor diet or lack of exercise. We must take supplements in the context of other healthy lifestyle choices, such as adequate nutrition, sleep, exercise, and working with a medical professional to treat any medical conditions. 

By Maya Shetty, BS and Sharon Brock, MEd, MS

“Salud!” If you’ve ever raised a glass to your health, you’re not alone. For decades, many have believed that minimal alcohol consumption is potentially beneficial for your health. However, not every researcher would agree. A growing body of evidence reveals health concerns about alcohol use, making it crucial to understand the spectrum from harmless to harmful levels of consumption to keep your body healthy. 

“Alcohol will impact everyone’s health differently,” says Douglas Noordsy, MD, Clinical Professor of Psychiatry at Stanford University School of Medicine and Assistant Director of Stanford Lifestyle Medicine. “Rather than a daily habit, drinking alcohol should be seen as an indulgence, something you have once in a while to celebrate.”

Experts have conflicting views regarding how much alcohol carries risks. Some believe that drinking in moderation is safe, while others believe that even light drinking can cause harm.

“While many believe light to moderate alcohol intake is safe and even healthy, this reality is far from true,” states Cindy Kin, MD, a colorectal surgeon and Associate Professor of Surgery at Stanford University. “In fact, no level of alcohol can be considered beneficial for our health.”

Isn’t One Glass of Red Wine Good for the Heart?

“Studies have gone back and forth, with some suggesting potential cardiovascular benefits of light drinking, while others point to increased risk of cancer and liver disease even when consumed at low intake levels. As a result, many are confused about headlines proclaiming alcohol as either good or bad for health,” says Dr. Noordsy.

The origin of this belief traces back to the 1980s, rooted in a concept known as The French Paradox–the observation that despite consuming a diet high in saturated fat, France had a low incidence of heart disease. Researchers of the era decided that this unexpected trend was attributed to the widespread consumption of wine in the region. This correlation led to extensive research into wine and the identification of polyphenols, thought to be responsible for wine’s apparent cardioprotective potential. 

Since then, numerous observational studies have claimed that light to moderate wine intake has beneficial effects. “However, these studies overlooked some crucial factors,” says Dr. Kin. While early observations indicated poorer cardiovascular outcomes for non-drinkers than for moderate drinkers, researchers overlooked that many non-drinkers abstained due to existing health conditions that led to overall poorer health outcomes. Additionally, those self-identified as light drinkers were more likely to lead healthier lifestyles overall. This oversight has fostered a misleading impression that associates better cardiovascular outcomes with light drinking, falsely implicating alcohol as the causal factor. As a result, enjoying a glass or two of wine a day has become widely accepted as a  healthy habit. 

While red wine contains antioxidants like resveratrol, found in grape skins as well as in peanuts, dark chocolate, and blueberries, which might have heart-healthy benefits like reducing cholesterol and lowering blood pressure, the quantities are often misunderstood. To achieve the levels of resveratrol observed beneficial in mice studies, one would need to consume an impractical amount of red wine—somewhere between a hundred to a thousand glasses daily. Thus, while the idea of resveratrol’s benefits is enticing, the practical reality makes it an unrealistic source for therapeutic effects.

How Much Alcohol is Too Much?

Many people believe alcohol becomes a concern only when consumed excessively. “Excessive alcohol use” is defined as exceeding the US Dietary Guidelines’ recommendations, which advise males to limit themselves to two drinks per day and females to one drink per day, on average. Two-thirds of adult drinkers report drinking above this level at least once a month.

However, a growing body of recent research shows that even modest quantities of alcohol can be harmful to our health. Such consistent findings have prompted the World Health Organization to assert that “when it comes to alcohol consumption, there is no safe amount that does not affect health.”

The main issue with alcohol is that it enters the bloodstream and quickly spreads throughout the entire body (especially when consumed without food). Unlike most substances, alcohol is both water- and fat-soluble, allowing it to permeate nearly every cell and tissue, including the highly secure blood-brain barrier that protects our central nervous system. 

While the liver does most of the alcohol metabolism, other organs also process alcohol, such as the kidneys and lungs. As our organs work to break it down into a usable fuel source, acetaldehyde is produced, which is toxic due to its ability to damage and kill cells indiscriminately. As acetaldehyde enters the brain, it causes a disruption in our neural circuitry that creates the sensation of “tipsiness” associated with alcohol. And, the more “tipsy” one feels, the greater the amount of toxic acetaldehyde in the blood.

Rather than following strict guidelines about how much to drink, Dr. Noordsy recommends that individuals take note of their personal perceptions of intoxication and pace themselves accordingly. He recommends using the feeling of being “tipsy” as the signal to slow down or stop drinking. “The ‘tipsy’ feeling is the indicator that blood alcohol levels have risen to the point that you’re starting to put your health at risk. And the more ‘tipsy’ you become, the higher the risk,” states Dr. Noordsy. “If you’re having alcohol with food, your blood alcohol level won’t be as high as compared to having drinks by themselves. So, if you’re enjoying a glass of wine as part of your meal, that’s a very different thing than drinking in a way that’s leading to the feeling of intoxication.”

Health Concerns Linked to Alcohol Use

Recent data from the World Health Organization reveals that each year, alcohol contributes to three million deaths globally and accounts for 5.1 percent of the worldwide burden of disease and injury. Alcohol’s detrimental effects span more than 200 disease and injury conditions, encompassing everything from alcohol dependence and liver cirrhosis to a range of non-communicable diseases (such as heart disease, cancer, chronic respiratory disease, and diabetes) and mental health disorders.

Liver Disease

Acetaldehyde, a derivative of alcohol metabolism, inflicts significant harm on the body’s cells, especially within the liver. Given the liver’s primary role in detoxifying our bloodstream, it bears the brunt of the detrimental effects of alcohol metabolism. This continual strain can result in the buildup of fat, chronic inflammation, and potentially irreversible damage to the liver. 

A study analyzing the livers of 3,649 participants discovered a concerning correlation: as daily alcohol intake increased, so did the accumulation of fat in the liver. Alarmingly, no identifiable threshold existed below which these harmful effects were absent, suggesting that even individuals who consume alcohol in minimal amounts are not immune to the accumulation of liver fat.

Fat accumulation hinders the liver’s vital metabolic functions, including blood sugar regulation, cholesterol processing, and nutrient absorption. It also increases the risk of inflammation around the liver, known as alcoholic hepatitis. 

“The good news is that abstaining entirely from alcohol can reverse these changes, however, continuing to drink alcohol can lead to irreversible damage, scarring, liver dysfunction, and in advanced cases, liver failure,” states Dr. Kin. “This is especially concerning because fatty liver often presents no early symptoms, with individuals potentially unaware until it advances or results in serious complications.”

Another important consideration is that people who have non-alcoholic fatty liver disease, caused by obesity and other metabolic syndromes, have a much higher risk of developing alcoholic liver disease. 

“This means that even small amounts of alcohol will cause the same level of alcohol-related liver disease (fibrosis, cirrhosis, etc.) as would larger amounts of alcohol consumed by someone without underlying fatty liver,” explains Dr. Kin. “Therefore, people who are already dealing with metabolic diseases should be extra cautious around alcohol because their livers are working extra hard already.”

Cancer

Alcohol is designated as a carcinogen by the International Agency for Research on Cancer due to its association with higher risk for many common cancers.

Alcohol increases cancer risk specifically in areas it is in close contact with, such as the mouth, pharynx, and digestive tract. It also has carcinogenic effects throughout other parts of the body,” states Dr. Kin.

Underlying its harmful effects, chronic inflammation from alcohol consumption elevates cell turnover, heightening DNA mutation risks. Additionally, alcohol is believed to promote tumor growth while inhibiting tumor-suppressive molecules.

In 2017, the European Union reported nearly 23,000 cancer cases tied to light to moderate alcohol use, with half attributed to female breast cancers. Even at levels as low as three drinks per week on average, there is a slight but measurable increase in breast cancer risk. Notably, raising daily alcohol intake by just 10 grams—equivalent to what’s in a standard beer or wine—escalates the risk of breast cancer by 10 percent.

Cardiovascular Health

Despite popular belief, alcohol consumption, regardless of the amount, is linked to an increased risk of cardiovascular disease. A comprehensive study of 371,463 individuals found that as alcohol consumption increased, so did the risks of conditions like hypertension and coronary artery disease. Light alcohol intake (less than 8.4 drinks per week) led to a minimal but noticeable increase in cardiovascular risk. Researchers also found that when accounting for various lifestyle factors, the perceived protective benefits of modest alcohol intake against cardiovascular risks diminished significantly.

There are numerous reasons hypothesized for these detrimental effects, especially surrounding the metabolic effects of alcohol. “Alcohol offers no nutritional benefits; it’s essentially empty calories that are consumed on top of the calories required by your body. On top of this, alcohol interrupts the body’s regular metabolic functions. As the body prioritizes removing this toxic substance, it compromises processes like nutrient absorption and fat metabolism. This disruption promotes the storage of visceral fat, the harmful fat surrounding organs,” explains Dr. Kin. “This fat increases inflammation and poses significant risks, especially around the heart.”

Hormone Imbalance

Alcohol consumption raises estrogen levels in both males and females by increasing the activity of the enzyme responsible for converting androgens to estrogen. This accelerated conversion can lead to issues like gynecomastia (enlarged breasts in males), decreased libido, and increased fat accumulation. Additionally, consistent alcohol exposure can reduce testosterone levels over time, which is associated with reduced libido, fatigue, decreased bone density and muscle mass, and potential fertility issues in both males and females.

Additionally, regular alcohol consumption of more than 3.5 drinks per week for males and 2.6 drinks per week for females can cause chronic changes and reduced control of the hypothalamic-pituitary-adrenal axis. This disturbance may lead to an increase of the stress hormone cortisol released throughout the day.

Microbiome Issues

Alcohol also disrupts the gut microbiome by killing beneficial bacteria and other essential microbes. Additionally, alcohol’s pro-inflammatory properties trigger the release of inflammatory cytokines, causing gut inflammation and making the intestinal lining more permeable. This increased permeability can allow undigested food particles to enter the bloodstream. Over time, chronic alcohol consumption can further imbalance the gut microbiome, promoting bacterial overgrowth and dysbiosis. These disruptions can trigger immune responses, increasing susceptibility to food intolerances.

Brain Health

When alcohol is consumed, it enters the brain and suppresses neural networks involved in memory formation and storage. Through chronic consumption, this disruption can have permanent effects. A study involving over 36,000 middle-aged adults revealed that even moderate drinkers, consuming one to two drinks per day on average, displayed thinning of the neocortex and other brain regions, indicating neuron loss. This research also found that increased alcohol consumption correlates with diminished brain volume and reduced gray matter, which are the areas of the brain highly concentrated with neurons. As alcohol intake rose, so did the severity of these detrimental effects. 

Fortunately, for most casual drinkers, abstaining from alcohol for two to six months can reverse damage to the prefrontal cortex and neural circuitry. However, chronic users may only experience partial recovery and might endure lasting effects.

“As alcohol consumption increases, so does one’s risk of cognitive decline and dementia,” states Dr. Noordsy.

Mental Health

As anxiety and depression continue to rise in the US, alcohol use also increases as individuals self-medicate to reduce stress. Also, the nightly glass of wine may cause more stress the following day since it impairs cognitive and physical performance, reducing one’s ability to cope. “During the pandemic, we observed a startling rise in cases of alcohol-induced hepatitis, indicating a growing reliance on alcohol as a coping mechanism,” says Dr. Kin. 

One study, however, showed that light to moderate alcohol consumption may be beneficial to mental health by offering short-term relief by reducing stress signals in the brain. Although Dr. Noordsy acknowledges this study, he states that “learning to manage stress through physical exercise, mind-body and mindfulness practices can lead to safer and likely more effective mediation of impacts of stress than relying on alcohol use.” 

Is There a Healthy Way to Consume Alcohol?

Given the extensive research on the detrimental health effects of alcohol, both Dr. Kin and Dr. Noordsy recommend abstaining from alcohol, or at least drinking very rarely, if one is experiencing or has a family history of liver disease, cancer, cardiovascular disease, hormone imbalances, gut microbiome issues, dementia, or mental health disorders, including addiction.

The precise amount of alcohol that is harmful is difficult for experts to confirm because it’s different for each person. Therefore, when it comes to alcohol and health, Dr. Noordsy recommends a balanced, personalized approach keeping in mind one’s individual risk factors and health goals.

“While heavy, regular consumption is linked to health problems, an occasional drink with meals may pose little risk for most adults,” says Dr. Noordsy. “However, individuals with personal or family histories of certain cancers or other conditions may need to be more careful with alcohol intake. We put thought into our nutrition and exercise habits, and we need to be just as thoughtful about the role that alcohol plays in our lives and make informed decisions regarding how much is the right amount for ourselves.”

Although less inclined to recommend light alcohol consumption, Dr. Kin acknowledges that it is an ingrained part of people’s social and cultural lives, similar to many other things that individuals consume that do not contribute to health. So, she encourages individuals to reframe their mindset around alcohol. 

“Rather than viewing alcohol as a daily routine, consider it a treat reserved for special occasions or celebrations, much like enjoying a slice of birthday cake,” she says.

By Carly Smith, BS, MPH(c) 

The foundation of longevity science exists in a balance of healthy physical, mental, and emotional aging. In the past, researchers have studied these aspects of health as independent subjects, but now scientists emphasize that every aspect of our health is intertwined. One of the major motivations behind the Stanford Lifestyle Medicine movement is to increase awareness of how total health is dependent upon the interactions between the pillars of our lives. 

Recently, members of the Stanford Lifestyle Medicine team collaborated to conduct a systematic review of existing research on “The Role of Physical Exercise in Cognitive Preservation.” The article, which was published in the American Journal of Lifestyle Medicine, responds to a call for more scientific investigations to focus on the prevention of cognitive disabilities associated with old age, such as dementia. 

“After conducting this review, a major takeaway is that we should be motivated beyond physical improvements to continue moving our bodies to promote long-term cognitive benefits,” says Matthew Kaufman, MD, lead author of the review article.

Exercise and the Brain

Both aerobic exercise and strength training are widely researched lifestyle interventions for quality health improvement.The US Department of Health and Human Services (USDHHS) recommends weekly exercise of at least ​​150 minutes of moderate-intensity aerobic exercise and two days of strength training for improving physical and mental health. 

There are multiple proposed mechanisms that define how regular physical activity combats cognitive decay. As you exercise, your heart increases the amount of blood that it pumps out to the rest of the body to compensate for the increased workload. This increase in cardiac output also increases cerebral blood flow, which is linked to heightened neural activity and reduced oxidative stress (or an improved ability to detoxify agents in the body). Another proposed mechanism is the increase in trophic factors (proteins that aid cell survival and growth), such as BDNF, VEGF, and IGF-1. These trophic factors support neuroplasticity (the structural reorganization of the brain to support learning) and angiogenesis (the growth of new blood vessels). Therefore, it is reasonable to promote exercise as a lifelong tool for optimizing brain health.

“It is important to understand the physiology of this relationship in order to maximize exercise regimens for prolonged cognitive benefits and goal setting,” says Dr. Kaufman, current Stanford Physical Medicine and Rehabilitation Resident.  

Key Takeaways from the Systematic Review

After reviewing over 1,600 total studies, 17 met the team’s final criteria for further analytical evaluation. To be included in the final review, studies must have been a randomized controlled trial published after 2000, excluded cognitive impairments more severe than moderate diagnoses, and included at least one physical activity intervention that lasted for 12 weeks or more and followed the USDHHS recommended guidelines. For this review, both aerobic exercise and strength training were included as exercise interventions. The final 17 studies selected for “qualitative synthesis” looked at the relationships of exercise and global cognition, exercise and memory, and exercise and executive function. 

The review team found the largest consensus in the research for improvements in memory for individuals with moderate, mild, or no cognitive impairments following the 12-week exercise interventions. For individuals with mild cognitive impairments, exercise was shown to improve cognition. Although weaker, there was also evidence found for relationships between regular exercise and improved global cognition and executive functioning. Some studies also found significant associations between improvements in physical and cognitive fitness and increases in regional brain volume or blood flow. 

However, included studies that analyzed the lasting effects of exercise following the study indicated a need for continued exercise. Improvements in memory and cognitive health were not always maintained once regular exercise stopped. This suggests the importance of exercise as a long-term principle of lifestyle medicine for adequate prevention of late-stage diseases. 

“Given that our review demonstrates that people did not see lasting benefits after stopping their exercise, the importance of routine exercise to continue reaping benefits is suggested,” says Dr. Kaufman. “It also strengthens our association that exercise interventions can, in fact, improve cognition.”