Month: August 2021

No one is truly allergic to the sun, but some people are quite sensitive to different types of sun rays and may develop mild to serious reactions after spending time in the sun.

There are several types of “sun allergies,” but polymorphous light eruption (PMLE), an autoimmune condition in the skin that occurs after sun exposure, is one of the most common. Other conditions considered as sun allergies are solar urticaria (hives and reddish patches that usually start 30 minutes to two hours after the sun exposure), actinic prurigo (papules and nodules that are intensely itchy on sun-exposed skin areas), and photoallergic reaction (when the UV rays from the sun modify the chemical structure of medications or products applied to the skin, and a person develops an allergy to the newly modified substance).

What causes PMLE?

People who have PMLE have immune cells that are triggered by sun rays, which attack their skin, and they develop a skin reaction to the sun’s the ultraviolet (UV) rays.

PMLE represents 70% of all sun-induced skin eruptions. It can affect both sexes and all skin types, and it usually starts when someone is a teen or young adult. PMLE may be an inherited condition. Being a female, having fair skin, and living in the north are other risk factors.

PMLE is more common in young women who live in temperate climates. People who live in temperate climates spend all winter out of the sun, so when it becomes warmer the sun exposure is intense. People who live in warmer climates are desensitized because they have a higher sun exposure all year.

What does PMLE look like?

PMLE can appear several hours or days after the first major sunlight exposure of the season, usually during spring or at the beginning of summer. The areas of the body generally affected the most are the ones that are covered during wintertime, but not in the summer: the neck, the chest, and the outer parts of the arms.

After exposure to the sun, people with PMLE usually notice reddish patches on their skin. These spots may itch, burn, or sting, but they typically don’t leave a scar. In more severe cases, the patches cover most of the body and may also be associated with headaches, fevers, tiredness, and low blood pressure. (If you experience these symptoms, see an urgent care provider for evaluation.) If you think you have PMLE or another sun allergy, a dermatologist is the best doctor to evaluate and treat your skin condition.

Does PMLE get better?

PMLE lesions often get better in approximately 10 days, and it’s important to avoid sun exposure until you are healed. People who develop PMLE can experience significant discomfort and have their life negatively impacted during the spring and summer months. However, repetitive sun exposure can make PMLE less likely to occur. The hardening effect, as it is called, means that the skin lesions that appear after the first episode are less severe, and they can be better tolerated during subsequent episodes.

What are current treatments for any sun allergy, including PMLE?

The best treatment is to prevent sun exposure. Avoid sunlight when it is most intense (from 10 a.m. to 4 p.m.), and use UV-protecting clothing or clothes made of darker and thicker fabrics, as they will prevent the UV rays coming from the sun from reaching your skin. Hats with a wide brim protect your scalp, face, and (partially) the neck.

Broad-spectrum sunscreens that protect your skin from both UVA and UVB rays should be used daily, even if it’s cloudy. Apply sunscreen on your face and any part of your skin that is not covered by a hat or clothing. Reapply sunscreen every two hours, and if you go swimming or get sweaty reapply more frequently (water-resistant sunscreen should also be reapplied).

If you develop PMLE, the areas of skin impacted can be treated with steroid creams. In severe cases, your doctor may recommend a short course of steroid pills. Medications that reduce the immune response, such as azathioprine, are options for treating PMLE, since it is an autoimmune condition (the body is attacking it is own healthy cells).

Antihistamines are medications typically used for allergies that may help shorten the duration of reddish patches that itch or burn, and they also reduce inflammation.

Hydroxychloroquine (a medication also used to treat malaria) can be used in case of flare-ups, or as a prevention method when people travel to sunny locations during winter vacations.

Oral Polypodium leucotomos extract, a natural substance derived from tropical fern leaves, may work as a potent antioxidant, and has anti-inflammatory properties that are beneficial in the prevention of PMLE. Other nutritional supplements containing lycopene and beta-carotene (vitamin A derivatives) have a similar effect. A dermatologist will guide you on the best way to use these medications.

The bottom line

Sun allergies are common in temperate climates, but with a dermatologist’s guidance, vigilant sun prevention, and medications they can be managed throughout the sunny months of the year.

About the Authors

Neera Nathan, MD, MSHS, Contributor

Dr. Neera Nathan is a dermatologist and researcher at Massachusetts General Hospital and Lahey Hospital and Medical Center. Her clinical and research interests include dermatologic surgery, cosmetic dermatology, and laser medicine. She is part of the … See Full Bio View all posts by Neera Nathan, MD, MSHS

Lais Lopes Almeida Gomes, Contributor

Dr. Lais Lopes Almeida Gomes is a dermatology research fellow at Massachusetts General Hospital, and a pediatric dermatologist in Brazil. Her clinical and research interests include atopic dermatitis and global health. She is part of the … See Full Bio View all posts by Lais Lopes Almeida Gomes

In the aftermath of the killing of 19 children and two adults in an elementary school in Uvalde, Texas, there is a lot of discussion — and argument — about what we should do to prevent shootings like this from happening.

In the midst of all the back and forth between banning guns and arming teachers, there is an important question that cannot be lost: what does it do to a generation of children to grow up knowing that there is nowhere they are safe?

There is increasing research that growing up amidst violence, poverty, abuse, chronic stress, or even chronic unpredictability affects the brains and bodies of children in ways that can be permanent. These adverse childhood experiences put the body on high alert, engaging the flight-or-fight responses of the body in an ongoing way. This increases the risk of depression, anxiety, and substance abuse, but it does so much more: the stress on the body increases the risk of cancer, heart disease, chronic disease, chronic pain, and even shortens the lifespan. The stress on the brain can literally change how it is formed and wired.

Long-term effects on a generation

Think for a moment about what this could mean: an entire generation could be forever damaged in ways we cannot change. The ramifications, not just for their well-being but for future generations and our work force and health care system, are staggering: stress like this can be passed on, and affects parenting.

As we talk about arming teachers and increasing armed police at schools, it is important to remember that research shows that the more guns, the higher the risk of homicide. It’s also important to remember that many children die every year from unintentional shootings in the home. In fact, guns have overtaken motor vehicle accidents as the leading cause of death in children. The idea of “arming the good guys” is an understandable response to horrible events like Uvalde, Parkland, and Sandy Hook, but the data would suggest that it may not be the most successful one. Violence begets violence, and guns aren’t reliably used the way we want them to be.

It’s not just guns, of course. There are other stressors, like poverty, community violence, child abuse, racism and all the other forms of intolerance, and lack of access to health care and mental health care. The pandemic has likely forever altered this generation in ways we cannot change, too.

The communities our children are growing up in and the world they are growing up in are increasingly becoming scary places. If we care about our children, if we care about our future, we need to stop fighting among ourselves and come together to create solutions that support the health and well-being of children, families, and communities. We need to nurture our children, not terrify them.

About the Author

Claire McCarthy, MD, Senior Faculty Editor, Harvard Health Publishing

Claire McCarthy, MD, is a primary care pediatrician at Boston Children’s Hospital, and an assistant professor of pediatrics at Harvard Medical School. In addition to being a senior faculty editor for Harvard Health Publishing, Dr. McCarthy … See Full Bio View all posts by Claire McCarthy, MD

While psychiatric medications can be essential for improving mental health and well-being, they often come with unwanted side effects. One particular side effect of many psychiatric medications is weight gain. In this post we will explore how these medications cause weight gain, and what you can do to lessen the impact of this unwanted effect of many psychiatric medications.

What are the different types of psychiatric medications?

There are five main types of psychiatric prescription medications: antidepressants, antipsychotics, anxiolytics (also known as anti-anxiety medications, which can include medications for sleep), mood stabilizers, and stimulants. Stimulants are not likely to cause weight gain. In fact, many of them reduce appetite and can cause weight loss as a side effect. These medications will not be discussed in this post.

Antidepressants can be divided into separate classes:

• SSRIs, or selective serotonin reuptake inhibitors, increase serotonin levels in the brain.
• SNRIs, or serotonin-norepinephrine reuptake inhibitors, increase both serotonin and norepinephrine in the brain.
• TCAs, or tricyclic antidepressants, increase serotonin, norepinephrine, and dopamine in the brain.
• MAOIs, or monoamine oxidase inhibitors, increase serotonin, dopamine, and norepinephrine in the brain.

Why do antidepressants cause weight changes?

All of these medications increase serotonin levels in the brain. Serotonin regulates mood and affects appetite, yet this can have varying results depending on length of treatment. Short-term use reduces impulsivity and increases satiety, which can reduce food intake and cause weight loss. However, long-term use (longer than a year) can cause downregulation of serotonin receptors, which subsequently causes cravings for carbohydrate-rich foods such as bread, pasta, and sweets that ultimately may lead to weight gain. The antidepressants with the highest risk of causing weight gain are amitriptyline, citalopram, mirtazapine, nortriptyline, trimipramine, paroxetine, and phenelzine.

Why do antipsychotic medications worsen obesity-related diseases?

Antipsychotics can also be categorized into two classes: typical and atypical antipsychotics. Both classes can cause weight gain, but they differ in that atypical antipsychotics cause fewer movement disorder side effects. Like antidepressants, antipsychotics affect the chemical messengers in the brain associated with appetite control and energy metabolism, namely serotonin, dopamine, histamine, and muscarinic receptors. In addition to causing weight gain, antipsychotics can also impair glucose metabolism, increase cholesterol and triglyceride levels, and cause hypertension, all of which can lead to metabolic syndrome and worsen obesity-related diseases. The antipsychotics most likely to cause weight gain are olanzapine, risperidone, and quetiapine.

What about anti-anxiety medications and weight changes?

There is no clear link between traditional anti-anxiety medications such as benzodiazepines and weight gain. However, many antidepressants are also used for the treatment of anxiety, and may cause weight gain as discussed above.

Similarly, not all medications for sleep cause weight gain; one that has been associated with weight gain is diphenhydramine (the active ingredient in Benadryl that is also used in many over-the-counter sleep aids). Diphenhydramine can contribute to weight gain by causing increased hunger and tiredness, which can make a person less active. Other sleep aids such as zolpidem (Ambien) or eszopiclone (Lunesta) have not been linked to weight gain.

Trazodone, a medication used for depression as well as insomnia, reduces excess serotonin at some sites, while increasing serotonin levels at other sites, thus affecting appetite as previously discussed.

Mood stabilizers are often used to treat bipolar disease, and can increase appetite or cause changes in metabolism. Although some antidepressants and antipsychotics are also used to treat bipolar disease, mood stabilizers such as lithium, valproic acid, divalproex sodium, carbamazepine, and lamotrigine are the mood stabilizers often used for treatment of bipolar disorder, and with the exception of lamotrigine, they are all known to increase the risk of weight gain.

There are effective strategies to minimize weight gain

For people taking psychiatric medications for mental health, there are strategies to minimize weight gain. Optimizing lifestyle and daily habits is important. This includes eating a healthy diet with whole foods and limiting processed foods and added sugars; staying physically active; minimizing stress; and ensuring adequate restful sleep. Physical activity, in particular, can have a double effect of both improving mental health and minimizing weight gain that might otherwise occur. Cognitive and behavioral strategies under the guidance of a psychologist may be useful for avoiding giving in to any increased cravings for sweets and carbohydrates.

Another strategy to minimize weight gain is to work with your healthcare provider to determine if there might be an appropriate alternate medication option with a lower risk of weight gain. In addition, the anti-diabetes medication metformin has been shown to be effective in treating and preventing psychotropic-induced weight gain. Other medications prescribed for weight loss may also be appropriate to help counteract the weight gain experienced by psychotropic medications.

Be aware that almost all medications have a risk of causing side effects, and it is important to ensure that the benefits of taking any medications will outweigh the risks. Speaking to your primary care provider, psychiatrist, or obesity medicine specialist can be useful in determining which options may work best for you.

About the Author

Chika Anekwe, MD, MPH, Contributor

Chika V. Anekwe, MD, MPH is an obesity medicine physician at Massachusetts General Hospital (MGH) Weight Center and Instructor in Medicine at Harvard Medical School (HMS). Her professional interests are in the areas of clinical nutrition, … See Full Bio View all posts by Chika Anekwe, MD, MPH

When trying intermittent fasting, both the quantity and quality of what you eat during your eating window matter.

Intermittent fasting is a trendy topic that arises repeatedly in my clinic these days. I get it: restrict the time period when you eat, but within that time window eat as you normally would. No calorie counting. No food restrictions. Simple and flexible. In an on-the-go world, intermittent fasting has come into vogue as a potential pathway toward sustainable weight loss.

What is Intermittent fasting?

Intermittent fasting (IF) has become a catch-all term for one of the key levers in our dietary pattern: timing. More accurately, intermittent fasting refers to an eating schedule that is designed to expand the amount of time your body experiences a fasted state. You achieve this by reducing the so-called eating window. The most popular time-restricted eating protocols (typically based on study designs) are explained in these previously published articles:

• Time to try intermittent fasting?
• Intermittent fasting: The positive news continues
• Not so fast: Pros and cons of the newest diet trend

How might time-restricted eating help with weight loss?

To start, consider a fed state that promotes cellular growth versus a fasted state that stimulates cellular breakdown and repair. Both can be beneficial or harmful, depending on the context (consider how cellular growth builds lean muscle mass and also spawns cancer). Many of our genes, particularly those that regulate our metabolism (how we digest and utilize the energy from food), are turned on and off each day in accordance with our innate circadian rhythms (our sleep/wake cycle).

We transition from a fed to an early fasted state several hours — five to six, on average — after our last meal. This often aligns with the time when the sun has set, our metabolism slows, and we sleep. However, in our modern environment with artificial lights, 24-hour convenience stores, and DoorDash, we are persistently primed to eat. Rather than obeying our circadian cues, we are eating at all times of day.

Plenty of research, mainly in animal models but also some human trials, indicates that your body experiences numerous benefits from being in a fasted state, given its impact on cellular processes and function. In a fully fasted state, your metabolism switches its primary source of fuel from glucose to ketones, which triggers a host of cellular signaling to dampen cellular growth pathways and increase cellular repair and recycling mechanisms. Repeated exposure to a fasted state induces cellular adaptations that include increased insulin sensitivity, antioxidant defenses, and mitochondrial function.

Given how much of chronic disease is driven by underlying insulin resistance and inflammation, it’s plausible that fasting may help reduce diabetes, high cholesterol, hypertension, and obesity. And multiple short-term clinical studies provide evidence that intermittent fasting — specifically, time-restricted feeding — can improve markers of cardiometabolic health.

Is intermittent fasting a reliable strategy to achieve weight loss?

To date, the answer has remained murky due to the quality of the evidence, which often involves very small sample sizes, short intervention periods, varied study designs (often lacking control groups), different fasting protocols, and participants of varying shapes and sizes. The data on intermittent fasting and its impact on weight loss largely involves studies that employ the time-restricted eating methodology of intermittent fasting. A recent compilation of the evidence suggests that limiting your eating window might indeed help you shed a few pounds.

New research on IF as a tool for weight loss

To tease out the independent impact of time restriction on weight loss, we need to evaluate a calorie-restricted diet combined with time-restricted eating, compared to time-restricted eating alone. The recent results of a yearlong study assessed this exact question: does time-restricted eating with calorie restriction produce greater effects on weight loss and metabolic risk factors in obese patients, as compared with daily calorie restriction alone?

To answer this question, the trial involved people ages 18 to 75 with BMIs between 28 and 45, notably excluding those who were actively participating in a weight-loss program or using medications that affect weight or calorie intake. Participants were instructed to follow a 25% calorie-reduced diet (1,500 to 1,800 calories per day for men and 1,200 to 1,500 calories per day for women) with a set ratio of calories from protein, carbs, and fats. In order to confirm adherence to the diet (a notorious challenge in diet studies), participants were encouraged to weigh foods and were required to keep a daily dietary log, photograph the food they ate, and note the times at which they ate with the use of a custom mobile app.

Half of the participants (those in the time-restricted eating group) were instructed to consume the prescribed calories within an eight-hour period, whereas the other half in the daily-calorie-restriction group consumed the prescribed calories without time restriction. All participants were also instructed to maintain their usual daily physical activity throughout the trial, to remove this variable and to isolate the timing of food intake as the only difference between the two groups.

After a full year, 118 patients successfully completed the study, with similar rates of adherence to the diet and composition of the diet between the two groups. Both groups lost a significant amount of weight: an average of about 18 pounds for the time-restricted eating group and 14 pounds for the daily-calorie-restriction group. The difference in weight loss between the two groups was not statistically significant, nor was there a significant difference in weight loss among subgroups when sorted by sex, BMI at baseline, or insulin sensitivity. The resulting improvements in blood pressure, lipids, glucose, and cardiometabolic risk factors were also similar between the two groups. This trial provides strong evidence that, all else being equal, restricting the eating window alone does not have a substantive impact on weight loss.

What does the new research on IF mean for you?

For most people (with notable exclusions of those who have diabetes, eating disorders, are pregnant or breastfeeding, or require food with their meds), a time-restricted eating approach appears to be a safe strategy that is likely to produce some weight loss, assuming you are not changing your current dietary pattern (eating more calories).

The weight loss effects of time-restricted eating derive primarily from achieving a negative energy balance. If you maintain your regular diet and then limit the time window during which you eat, it is likely that you will eat a few hundred fewer calories per day. If this is sustainable as a lifestyle, it could add up to modest weight loss (3% to 8% on average, based on current data) that can produce beneficial improvements in cardiometabolic markers such as blood pressure, LDL cholesterol and triglyceride levels, and average blood sugar.

But — and this is a big but — if you are overcompensating for the time restriction by gorging yourself during your eating window, it will not work as a weight loss strategy. And it may indeed backfire. The other two levers in your dietary pattern — the quantity and quality of what you eat during your eating window — still matter immensely!

One downside of IF: Loss of lean muscle mass

While weight loss for cardiometabolic health is a sensible goal, weight loss from any intervention (including intermittent fasting) often entails a concurrent loss of lean muscle mass. This has been a notable finding — what I might even call an adverse side effect — of intermittent fasting protocols. Given the importance of lean muscle mass for revving your metabolic rate, regulating your blood sugar, and keeping you physically able overall, pairing resistance training with an intermittent fasting protocol is strongly advised.

Finally, the weight loss achieved through time-restricted eating (which we often refer to interchangeably with intermittent fasting) is likely different than the cellular adaptations that happen with more prolonged fully fasted states. At this time, it is hard to determine the degree to which the cardiometabolic benefits of fasting derive from weight loss or from underlying cellular adaptations; it is likely an interrelated combination of both.

Nevertheless, it seems clear that in a 24/7 world of around-the-clock eating opportunities, all of us could benefit from aligning with our circadian biology, and spend a bit less time in a fed state and more time in a fasted state each day.

About the Author

Richard Joseph, MD, Contributor

Dr. Richard Joseph is the founder of VIM Medicine, cofounder of Vital CxNs, a practicing clinician in the Center for Weight Management and Wellness at Brigham and Women’s Hospital in Boston, MA, and a faculty member at Harvard … See Full Bio View all posts by Richard Joseph, MD