Month: February 2022

Melasma is a pigmentation disorder of the skin mostly affecting women, especially those with darker skin. It is commonly seen on the face, and appears as dark spots and patches with irregular borders. Melasma is not physically harmful, but studies have shown that it can lead to psychological problems and poorer quality of life due to the changes it causes in a person’s appearance.

Melasma is a common disorder, with a prevalence of 1% that can increase to 50% in higher-risk groups, including those with darker skin. Melasma is known as the “mask of pregnancy” since hormonal changes caused by pregnancy, as well as hormonal medications such as birth control pills, are major triggers for excessive skin pigment production in melasma. Sun exposure is another important contributor to melasma.

Can melasma be prevented?

Currently, melasma cannot be fully prevented in people who are likely to develop this condition due to their genetics, skin color type, hormones, or sun exposure level. Avoiding direct sun exposure during peak hours (10 a.m. to 4 p.m.), diligently using high-SPF sunscreens, and avoiding hormonal medications when possible may help protect against melasma flares and reduce their recurrence after treatment. Strict sun protection is the mainstay of any melasma treatment regimen.

What sunscreen should melasma patients use?

Choosing an appropriate sunscreen is critical if you develop melasma, and studies have shown that broad-spectrum tinted sunscreens, especially ones containing iron oxide, can lower pigment production in the skin in melasma patients, as they block visible light as well as UVA/UVB rays. Non-tinted sunscreens, on the other hand, do not block visible light.

For some people, it might be more convenient to use cosmetic products such as foundations that contain both UVA/UVB blockers and visible light blockers such as iron oxide. These products can conceal dark spots and therefore alleviate the psychosocial impact of melasma, and at the same time act as a sunscreen to protect against darkening of the lesions.

It is important for people with melasma to know that visible light can go through windows, and therefore even if they are not out in the sun, they can still get melasma flares by exposing themselves to visible light while driving or sitting by a window.

Can melasma be treated?

Currently there is no cure for melasma; however, there are several medications and procedures available to manage this condition. It is important to know that these treatment options may result in an incomplete response, meaning that some of the discolorations become lighter or disappear while some remain unchanged. In addition, frequent relapses are common.

It is also important to be aware of possible side effects of treatment, including darkening of the skin caused by inflammation induced by the treatment, or extra lightening of the skin in a treated area. Using the appropriate medications under the supervision of a dermatologist can help achieve treatment goals and maintain them with fewer relapses.

Common melasma treatments

The most commonly used treatments for melasma are skin lightening medications that are applied topically. These include medications such as hydroquinone, azelaic acid, kojic acid, niacinamide, cysteamine, rucinol, and tranexamic acid. These medications work by reducing pigment production and inflammation, and by reducing excess blood vessels in the skin that contribute to melasma.

Pregnant women (who constitute a big proportion of melasma patients) should avoid most of these medications except for azelaic acid, which is a safe choice during pregnancy. Hydroquinone is a commonly used skin lightener that should only be used for a limited time due to side effects that may happen with prolonged use. It can be used for up to six months for initial treatment and then occasionally if needed.

In most patients a combination therapy is needed for treatment for melasma. A common choice is the combination of hydroquinone with a retinoid that increases skin cell turnover and a steroid that decreases skin inflammation. Oral medications, including tranexamic acid, are usually considered in more severe melasma cases. This medication is thought to help melasma by reducing pigment production and by reducing excess blood vessels in the skin.

Additional treatment procedures may help

If your melasma does not improve with topical or oral medications, adding procedures such as chemical peels and laser therapies to a treatment regimen could be beneficial.

Chemical peels use substances like glycolic acid, alpha-hydroxy acids, and salicylic acid to remove the superficial layer of the skin that contains excess pigment in melasma patients. The effects of a chemical peel are temporary, since this procedure removes a layer of skin without reducing the production of pigment in regenerating deeper layers.

Laser therapies can destroy pigment cells in skin and therefore lighten the dark spots in melasma. However, as with any other treatment option for melasma, there is considerable risk of relapse post-treatment.

Maintenance therapy and prevention

After achieving improvement of melasma lesions, strict sun protection and maintenance therapy need to be continued. Skin lighteners other than hydroquinone can be used in combination with retinoids to maintain the results, and hydroquinone therapy may be used intermittently if needed.

Takeaway message about melasma

The key point in management of melasma is to use sun protection all the time, and to avoid other triggers such as hormonal medications when possible. Since none of the available treatments are a cure, prevention is the best option. People with melasma should see a board-certified dermatologist for evaluation and appropriate treatment regimens to manage melasma and maintain the treatment results.

About the Authors

Lilit Garibyan, MD, PhD, Contributor

Dr. Lilit Garibyan is an assistant professor of dermatology at Harvard Medical School, and a physician-scientist at the Wellman Center for Photomedicine at Massachusetts General Hospital. Her research focuses on innovative biomedical discoveries aimed at identifying … See Full Bio View all posts by Lilit Garibyan, MD, PhD

Sara Moradi Tuchayi, MD, MPH, Contributor

Dr. Sara Moradi Tuchayi is a dermatology research fellow at Massachusetts General Hospital. Her research at the Wellman Center for Photomedicine at MGH is focused on the development of novel therapies for skin disorders. See Full Bio View all posts by Sara Moradi Tuchayi, 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