Belezzion

Let’s face it: inflammation has a bad reputation. Much of it is well-deserved. After all, long-term inflammation contributes to chronic illnesses and deaths. If you just relied on headlines for health information, you might think that stamping out inflammation would eliminate cardiovascular disease, cancer, dementia, and perhaps aging itself. Unfortunately, that’s not true.

Still, our understanding of how chronic inflammation can impair health has expanded dramatically in recent years. And with this understanding come three common questions: Could I have inflammation without knowing it? How can I find out if I do? Are there tests for inflammation? Indeed, there are.

Testing for inflammation

A number of well-established tests to detect inflammation are commonly used in medical care. But it’s important to note these tests can’t distinguish between acute inflammation, which might develop with a cold, pneumonia, or an injury, and the more damaging chronic inflammation that may accompany diabetes, obesity, or an autoimmune disease, among other conditions. Understanding the difference between acute and chronic inflammation is important.

These are four of the most common tests for inflammation:

• Erythrocyte sedimentation rate (sed rate or ESR). This test measures how fast red blood cells settle to the bottom of a vertical tube of blood. When inflammation is present the red blood cells fall faster, as higher amounts of proteins in the blood make those cells clump together. While ranges vary by lab, a normal result is typically 20 mm/hr or less, while a value over 100 mm/hr is quite high.
• C-reactive protein (CRP). This protein made in the liver tends to rise when inflammation is present. A normal value is less than 3 mg/L. A value over 3 mg/L is often used to identify an increased risk of cardiovascular disease, but bodywide inflammation can make CRP rise to 100 mg/L or more.
• Ferritin. This is a blood protein that reflects the amount of iron stored in the body. It’s most often ordered to evaluate whether an anemic person is iron-deficient, in which case ferritin levels are low. Or, if there is too much iron in the body, ferritin levels may be high. But ferritin levels also rise when inflammation is present. Normal results vary by lab and tend to be a bit higher in men, but a typical normal range is 20 to 200 mcg/L.
• Fibrinogen. While this protein is most commonly measured to evaluate the status of the blood clotting system, its levels tend to rise when inflammation is present. A normal fibrinogen level is 200 to 400 mg/dL.

Are tests for inflammation useful?

In certain situations, tests to measure inflammation can be quite helpful.

• Diagnosing an inflammatory condition. One example of this is a rare condition called giant cell arteritis, in which the ESR is nearly always elevated. If symptoms such as new, severe headache and jaw pain suggest that a person may have this disease, an elevated ESR can increase the suspicion that the disease is present, while a normal ESR argues against this diagnosis.
• Monitoring an inflammatory condition. When someone has rheumatoid arthritis, for example, ESR or CRP (or both tests) help determine how active the disease is and how well treatment is working.

None of these tests is perfect. Sometimes false negative results occur when inflammation actually is present. False positive results may occur when abnormal test results suggest inflammation even when none is present.

Should you be routinely tested for inflammation?

Currently, tests of inflammation are not a part of routine medical care for all adults, and expert guidelines do not recommend them.

CRP testing to assess cardiac risk is encouraged to help decide whether preventive treatment is appropriate for some people (such as those with a risk of a heart attack that is intermediate — that is, neither high nor low). However, evidence suggests that CRP testing adds relatively little to assessment using standard risk factors, such as a history of hypertension, diabetes, smoking, high cholesterol, and positive family history of heart disease.

So far, only one group I know of recommends routine testing for inflammation for all without a specific reason: companies selling inflammation tests directly to consumers.

Inflammation may be silent — so why not test?

It’s true that chronic inflammation may not cause specific symptoms. But looking for evidence of inflammation through a blood test without any sense of why it might be there is much less helpful than having routine healthcare that screens for common causes of silent inflammation, including

• excess weight
• diabetes
• cardiovascular disease (including heart attacks and stroke)
• hepatitis C and other chronic infections
• autoimmune disease.

Standard medical evaluation for most of these conditions does not require testing for inflammation. And your medical team can recommend the right treatments if you do have one of these conditions.

The bottom line

Testing for inflammation has its place in medical evaluation and in monitoring certain health conditions, such as rheumatoid arthritis. But it’s not clearly helpful as a routine test for everyone. A better approach is to adopt healthy habits and get routine medical care that can identify and treat the conditions that contribute to harmful inflammation.

About the Author

Robert H. Shmerling, MD, Senior Faculty Editor, Harvard Health Publishing

Dr. Robert H. Shmerling is the former clinical chief of the division of rheumatology at Beth Israel Deaconess Medical Center (BIDMC), and is a current member of the corresponding faculty in medicine at Harvard Medical School. … See Full Bio View all posts by Robert H. Shmerling, MD

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

Loud snoring, grunts, and gasps can be a sign of obstructive sleep apnea, a serious disorder that causes repeated, brief pauses in breathing (apneas) throughout the night. It can leave people drowsy and depressed, and put them at risk for high blood pressure, heart disease, and other health problems.

If this sounds like you or a bed partner, a recent spate of advertisements for a mask-free treatment for the disorder may catch your attention. Known medically as a hypoglossal nerve stimulator, the pacemaker-like device moves the tongue forward during sleep. That helps reopen a collapsed airway — the root cause of obstructive sleep apnea. But how does it compare with other treatments, and who might be a good candidate?

A second-choice therapy for sleep apnea

Marketed under the name Inspire, the device was approved by the FDA in 2014. It’s a second-choice therapy intended only for people who can’t tolerate positive airway pressure (known as PAP or CPAP), according to Dr. Rohit Budhiraja, a pulmonary and sleep specialist at Harvard-affiliated Brigham and Women’s Hospital.

“Sleep apnea causes the muscles in the back of the throat to collapse, which leads to pauses in breathing that wake you up again and again,” he says. PAP, the gold standard therapy for sleep apnea, prevents airway collapse by using a small bedside machine attached to tubing that blows air through a face mask.

This can improve a measurement called the apnea-hypoxia index (AHI) by approximately 90%, lowering it below 5 in most people. The AHI is a score that gauges the severity of sleep apnea. An AHI between 5 and 14 is considered mild; between 15 and 29 is moderate; 30 and higher is severe.

Targeting tongue muscles is less effective

Inspire targets only the muscles of the tongue rather than the entire airway, so it isn’t as effective as PAP. In fact, the company’s stated treatment goal is to lower a person’s AHI by just 50% (or below 20), although some people may do better.

Because PAP is more effective, sleep specialists encourage people to stick with it by trying different strategies. But research suggests a quarter to a third of people have a hard time using PAP (see here and here). When that’s the case, Inspire may be an alternative, says Dr. Budhiraja.

Who might consider hypoglossal nerve stimulation?

In addition to trying PAP without success, you also must

• have moderate to severe sleep apnea (an AHI score of 15 to 65)
• have a body mass index (BMI) of 32 or lower (although some centers allow BMI values as high as 35), which means the device is not right for people in some weight ranges.

If you meet these criteria, you can ask your doctor for a referral to a sleep specialist or an ear, nose, and throat surgeon. The next step is sleep endoscopy. While you are sedated, a doctor passes a small tube with a light and a tiny video camera on one end through a nostril to examine your upper airway. Up to a quarter of people have an airway collapse pattern that can’t be remedied with Inspire, Dr. Budhiraja notes. And, as noted, others have too high an AHI score to try it.

A surgical procedure requiring general anesthesia

The device is implanted during a short, same-day procedure done under general anesthesia. A generator is placed just below the collarbone, a breathing sensor at the side of the chest by the ribs, and a stimulation electrode around the hypoglossal nerve under the tongue.

As with all surgery, possible risks include bleeding and infection. Some people experience tongue weakness, which can cause slightly slurred speech and minor swallowing problems. But this usually resolves within a few days, or for most people, within a few weeks.

The device must be activated a month after surgery at a sleep laboratory. The breathing sensor monitors your breathing and, when necessary, it tells the generator to send a small electrical pulse to the electrode to make the tongue muscles contract. The stimulation moves your tongue forward so you can breathe normally.

How does it feel?

“Some people describe a mild tingling sensation, but most say the feeling is hard to describe,” says Dr. Budhiraja.

At home, you use a small remote control to turn the device on at night and off in the morning. The remote is set to gradually increase the level of stimulation once or twice a week as tolerated until you reach the highest level. You then return to the sleep lab for a study to determine your optimal range. The remote is then programmed to that range.

Some people start noticing a difference in their sleep quality even at the lowest levels of stimulation. Yearly checks are recommended thereafter, and the replaceable battery lasts about 11 years. Medicare and most major insurance plans cover Inspire.

Once it’s working, hypoglossal nerve stimulation is definitely convenient: no maintenance, cleaning, or buying supplies as required with a PAP machine. “But because Inspire is less effective, it’s not considered a replacement for PAP,” says Dr. Budhiraja.

About the Author

Julie Corliss, Executive Editor, Harvard Heart Letter

Julie Corliss is the executive editor of the Harvard Heart Letter. Before working at Harvard, she was a medical writer and editor at HealthNews, a consumer newsletter affiliated with The New England Journal of Medicine. She … See Full Bio View all posts by Julie Corliss

Asthma is the most common chronic lung disease in children. In the US, it affects about 6 million children, or about one in every 12 children.

Breathing is key to life, obviously, so asthma can make life very hard. It can make going for a walk outside feel very hard. It leads not just to visits with the doctor or to the emergency room, and to hospitalizations, but also to missed school, missed work for parents, missed events, and missed activities.

The good news is that asthma is very treatable. If parents, children, and doctors work together, a child with asthma can lead a healthy, normal life. Here’s what you need to know and do.

Know your child’s symptoms

Wheezing is definitely a symptom of asthma, but a dry persistent cough can be as well (for some children, this occurs mostly at night).

Watch for signs that a child is working harder to breathe. One sign is skin tugging inward between, on top of, or below the ribs. Difficulty talking in long sentences is another sign of this.

Some children with exercise-induced asthma avoid exercise; if your child is choosing to be less active, talk to them about why.

Know your child’s triggers

There are many different triggers for asthma, including:

• Upper respiratory infections, like the common cold. COVID falls into this category, which is why children with asthma should be vaccinated against COVID.
• Allergies, such as
  • outdoor allergens like pollen, which are often worse in the spring and fall
  • indoor allergens like dust mites or mold
  • pet dander.
• Exercise. Some children will struggle with even mild exercise, while others only have trouble with vigorous exercise or exercising when there are other triggers too (like a cold or allergies).
• Weather changes, especially to colder weather. Some children can be triggered by going into a cold, air-conditioned room.
• Stress. Stress affects our bodies in multiple ways, and in some people it can trigger their asthma or make it worse.

Understand your child’s medications

Several kinds of medicines are used to treat asthma, including:

• Bronchodilators. Examples are albuterol, levalbuterol, formoterol, or ipratropium. Known as “rescue medications,” these are inhaled and work by opening up the airways. They are given through metered-dose inhalers or a nebulizer machine. They are used when a person is experiencing symptoms.
• Inhaled steroids. These work by decreasing inflammation in the lungs and making them less likely to react to triggers. They are “controller medications” given regularly to prevent symptoms.
• Combined inhalers. These have both an inhaled steroid and a long-acting bronchodilator. They are very useful for patients with more difficult asthma. Sometimes they are used in SMART (Single Maintenance And Reliever Therapy), in which the same inhaler is used for both rescue and control.
• Oral or injected steroids. These are generally used when someone has a bad asthma attack, but some people need to take them regularly to prevent attacks.
• Allergy medications. Medicines like loratadine, cetirizine, or montelukast can be very helpful when there is an allergic component to asthma.

Some people with severe asthma need other treatments, such as allergy shots for severe allergies, or medications like dupilumab that work in the body to flight inflammation. This is far less common.

Use medication correctly

• Sometimes medications and medication regimens can be confusing. That’s why everyone with asthma should have a written Asthma Action Plan that spells out exactly what they should do and when.
• If your child uses an inhaler, make sure that they are doing it right! For most inhalers, it’s important to use a spacer, which is a tube that attaches to the inhaler and helps to ensure that the medication gets into the lungs and not just the mouth or surrounding air.
• If you have any questions about anything your child is prescribed, call your doctor.

Meet with your doctor regularly

If your child’s asthma is anything more than very mild (a few mild attacks a year), you need to check in more frequently than at the yearly checkup. Extra check-ins give you a chance to talk to your doctor about how things are going — and give your doctor a chance to tweak your child’s regimen so that your child can live the healthiest, happiest life possible.

Which, after all, is totally the point.

Follow me on Twitter @drClaire

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

I recently learned about a study suggesting a vegan diet is an effective treatment for rheumatoid arthritis.

While that sounded intriguing, another claim made in an interview about the study really caught my attention: the lead author of the study said that physicians should encourage people with rheumatoid arthritis to try changing their eating patterns before turning to medication.

Before turning to medication? Now wait just a minute. That flies in the face of decades of research convincingly demonstrating the importance of early medication treatment of rheumatoid arthritis to prevent permanent joint damage. An increasing number of effective treatments can do just that.

In fact, there’s no convincing evidence that changes in diet can prevent joint damage in rheumatoid arthritis. And that includes this new study.

So, what did this research find? Let’s take a look.

A vegan diet for rheumatoid arthritis

Researchers enrolled 44 people with rheumatoid arthritis in the study. All were women, mostly white and highly educated. They were randomly assigned to one of two groups for 16 weeks:

• Vegan diet. Participants followed a vegan diet for four weeks, followed by additional food restrictions that eliminated foods the researchers considered to be common arthritis trigger foods. These foods included gluten-containing grains (wheat, barley, and rye), white potatoes, sweet potatoes, chocolate, citrus fruits, nuts, onions, tomatoes, apples, bananas, coffee, alcohol, and table sugar. After week seven, these foods were reintroduced, one at a time. Any reintroduced food that seemed to cause pain or other symptoms of rheumatoid arthritis was eliminated for the rest of the 16-week period.
• Usual diet plus placebo. These participants followed their usual diet and took a placebo capsule each day for 16 weeks. The capsule contained insignificant doses of omega-3 fatty acids and vitamin E.

After the first 16 weeks, participants took four weeks off, then the groups swapped dietary assignments for an additional 16 weeks.

What did the study find about the vegan diet?

The vegan approach seemed to help lessen arthritis symptoms. Study participants reported improvement while on the vegan diet, but no improvement during the placebo phase.

For example, the average number of swollen joints fell from 7 to 3.3 in the vegan diet group, but actually increased (from 4.7 to 5) in the placebo group. In addition, while on the vegan diet, participants lost an average of 14 pounds, while those on the placebo gained nearly 2 pounds.

What else do we need to consider?

While the findings sound great, the study had significant limitations:

• Size. Only 44 study subjects enrolled and only 32 completed the study. With such small numbers, it only takes a few to alter the results. Larger studies (with several hundred or more participants) tend to be more reliable.
• Lack of diversity. This trial did not include men and had mostly white, highly educated participants.
• No standard diagnosis of rheumatoid arthritis. A physician’s diagnosis was required, but there was no requirement that standard criteria be met.
• Study duration. A treatment lasting four months may seem like a long time, but for a chronic disease like rheumatoid arthritis that can wax and wane on its own, this is too short a time to make firm conclusions.
• Self-reported diet. We don’t know how well study subjects stuck to their assigned diets.
• Medication use. Study subjects took arthritis medications, though no information on specific drugs is offered. Some made dosage adjustments during the trial. While the researchers tried to account for this through a separate analysis, the small number of participants could make that analysis unreliable.
• Weight loss. Losing weight, rather than eating a vegan diet, might have contributed to symptom improvement.
• No assessment of joint damage. No x-rays, MRI results, or other assessments of joint damage were provided. That’s important, because we know that people with arthritis can feel better even when joint damage continues to worsen. Steroids and ibuprofen are good examples of treatments that reduce symptoms of rheumatoid arthritis without protecting the joints. Without information about joint damage, it’s impossible to assess the true benefit or risk of relying on a vegan diet to treat rheumatoid arthritis.

Finally, it’s unclear how a vegan diet would improve rheumatoid arthritis. This raises the possibility that the findings won’t hold up.

Should everyone with rheumatoid arthritis become vegan?

No, there isn’t enough evidence to justify recommending a vegan diet — or any restrictive diet — for everyone with rheumatoid arthritis.

That said, a plant-rich diet is healthy for nearly everyone. As long your diet is nutritionally balanced and palatable to you, I see little harm in adopting an anti-inflammatory diet. But in the case of rheumatoid arthritis, diet should be combined with medicationto prevent joint damage, not used instead of it.

The bottom line

Growing evidence suggests diet can play a role in treating rheumatoid arthritis. But it’s one thing for a person to feel better on a particular diet; it’s quite another to say diet is enough by itself.

For high cholesterol or high blood pressure, dietary changes are the first choice of treatment. But rheumatoid arthritis is different. Disabling joint damage can occur early in the disease, so it’s important to start taking effective medications as soon as possible to prevent this.

We will undoubtedly see more research exploring the impact of diet on rheumatoid arthritis, other forms of arthritis, and other autoimmune disorders. Perhaps we’ll learn that a vegan diet is highly effective and can take the place of medications in some people. But we aren’t there yet.

About the Author

Robert H. Shmerling, MD, Senior Faculty Editor, Harvard Health Publishing

Dr. Robert H. Shmerling is the former clinical chief of the division of rheumatology at Beth Israel Deaconess Medical Center (BIDMC), and is a current member of the corresponding faculty in medicine at Harvard Medical School. … See Full Bio View all posts by Robert H. Shmerling, MD

Many people seek medical attention when they have diarrhea, usually when it is severe or is not improving. Doctors like myself ask questions to see what could be causing the problem: Food poisoning? Irritable bowel syndrome? Medication side effects? We also consider that diarrhea may be due to Clostridioides difficile infection (CDI).

What is C. diff infection?

CDI is a bacterial infection that can cause severe problems in the gastrointestinal tract, especially the colon. C. diff is responsible for almost half a million infections in the US each year, and it can be a recurring problem: one in six patients with this infection will get it again within two months. Sadly, one in 11 patients over age 65 who is hospitalized for CDI will die within one month of infection due to the severity of illness in CDI. Therefore, CDI is an important public health consideration, and it’s important to get treatment.

Who at risk for C. diff infection?

There are certain risk factors for developing a CDI. These include being hospitalized, having been exposed to antibiotics, or having close contact with someone who has been diagnosed with the infection. If you are immunocompromised (have a weakened immune system), you may be also at higher risk of contracting CDI or of suffering a complication from it.

A major focus of reducing the burden of CDI in the healthcare system is trying to reduce the risk of getting CDI in the hospital. This includes testing for CDI in hospitalized patients who develop new diarrhea, and then isolating those patients into their own rooms.

Prevention also includes washing your hands thoroughly with soap and water. This is a particularly important point because in healthcare settings, alcohol-based sanitizer often is used for convenience when clinicians practice preventive infection control between caring for patients. Alcohol-based sanitizer is not effective against CDI as it is for other types of infection because, unlike other bacteria, C. diff organisms can form resistant spores.

So, to protect yourself in health care settings, you should make sure the people who interact with you — doctors, nurses, medical assistants, etc. — have washed their hands prior to touching you. It can seem rude to ask someone if they have washed their hands. However, all people who work with patients receive training about hand-washing, and sometimes we simply forget in the middle of busy days, so it can be helpful to remind us.

What about CDI transmission outside of medical settings?

What is less understood is when CDI happens outside the hospital. A recent article in Emerging Infectious Diseases reported the presence of CDI in patients who became infected in a way that doctors tend not to think of as often: getting CDI from someone they know without ever being hospitalized or taking antibiotics themselves.

As physicians, we are drilled on the factors previously mentioned — prior use of antibiotics, previous hospitalization — as critical events that may cause CDI. What this research demonstrated is that people without these risk factors developed CDI by being exposed to someone with CDI in the community. It turns out that this is a common way people end up contracting CDI. During my training, we learned that it is important to remind patients newly diagnosed with CDI to be mindful of good hand hygiene, and to avoid as many contacts as possible until their CDI treatments were completed. This new research suggests that focusing on community CDI transmission should be a greater priority.

How is CDI treated?

The first round of CDI treatment is usually antibiotics (ironic, since antibiotics can cause CDI). These include metronidazole, vancomycin (in oral form only), and fidaxomicin. Every few years guidelines are reviewed and updated, but generally, different antibiotic treatment courses are given based on CDI illness severity, whether there is an infection that is failing to clear, or if a new antibiotic needs to be tried.

A promising way to treat CDI, particularly in patients who have not been helped by antibiotic therapy, is to give a fecal microbiota transplant, or FMT. This treatment involves taking a healthy person’s stool donation and administering it during an endoscopy procedure by mouth, during a colonoscopy, or in frozen form by pill. I know — taking someone else’s poop sounds so icky! However, the purpose is to introduce healthy bacteria into a gut that is sick with CDI, and the theory is that these healthy bacteria expand and make the environment harder for the C. diff bacteria to live and cause problems.

What precautions help prevent spread ofCDI?

The rules are simple for reducing your risk of CDI. If you have a weakened immune system, stay away from people who have been diagnosed with CDI. Thoroughly wash your hands with soap and water (not disinfectant) to deal with C. diff spores more effectively. When you are sick, take antibiotics only if they are necessary; doctors often feel pressured to write antibiotic prescriptions for people who have viral illnesses (for which antibiotics do not work).

Evidence is not strong for taking probiotics or eating yogurt to prevent CDI, but these approaches are low-risk ways to introduce healthy bacteria into your gut; this may be reasonable, in part because some in the medical field continue to debate their effectiveness.

Bottom line: if you are having diarrhea that just won’t go away, talk to your doctor to see if you have CDI or if there is something else causing your symptoms.

About the Author

Christopher D. Vélez, MD, Contributor

Dr. Christopher Vélez is an attending gastroenterologist in the Center for Neurointestinal Health of Massachusetts General Hospital's division of gastroenterology and the MGH department of medicine. He focuses on neurogastroenterology and motility disorders of the esophagus, … See Full Bio View all posts by Christopher D. Vélez, MD

For most Americans, a daily multivitamin is an unnecessary habit.

Are you among the one in three Americans who gulps down a multivitamin every morning, probably with a sip of water? The truth about this popular habit may be hard to swallow.

“Most people would be better off just drinking a full glass of water and skipping the vitamin,” says Dr. Pieter Cohen, an associate professor of medicine at Harvard Medical School and an internist at Harvard-affiliated Cambridge Health Alliance. In addition to saving money, you’ll have the satisfaction of not succumbing to misleading marketing schemes.

That’s because for the average American adult, a daily multivitamin doesn’t provide any meaningful health benefit, as noted recently by the US Preventive Services Task Force (USPSTF). Their review, which analyzed 84 studies involving nearly 700,000 people, found little or no evidence that taking vitamin and mineral supplements helps prevent cancer and cardiovascular disease that can lead to heart attacks and stroke, nor do they help prevent an early death.

“We have good evidence that for the vast majority of people, taking multivitamins won’t help you,” says Dr. Cohen, an expert in dietary supplement research and regulation.

Who might need a multivitamin or individual supplements?

There are some exceptions, however. Highly restrictive diets and gastrointestinal conditions, or certain weight-loss surgeries that cause poor nutrient absorption, are examples of reasons why a multivitamin or individual vitamins might be recommended. A daily vitamin D supplement may be necessary when a person gets insufficient sun exposure. Your doctor may recommend an iron supplement if you have a low red blood cell count (anemia).

Why is it hard to give up the habit of a daily multivitamin?

Surveys suggest people take vitamins to stay healthy, feel more energetic, or gain peace of mind, according to an editorial that accompanied the USPSTF review. These beliefs stem from a powerful narrative about vitamins being healthy and natural that dates back nearly a century.

“This narrative appeals to many groups in our population, including people who are progressive vegetarians and also to conservatives who are suspicious about science and think that doctors are up to no good,” says Dr. Cohen.

Unproven marketing claims for dietary supplements

Vitamins are very inexpensive to make, so the companies can sink lots of money into advertising, says Dr. Cohen. But because the FDA regulates dietary supplements as food and not as prescription or over-the-counter drugs, the agency only monitors claims regarding the treatment of disease.

For example, supplement makers cannot say that their product “lowers heart disease risk.” But their labels are allowed to include phrases such as “promotes a healthy heart” or “supports immunity,” as well as vague promises about improving fatigue and low motivation.

“Supplement manufacturers are allowed to market their products as if they have benefits when no benefit actually exists. It’s enshrined into the law,” says Dr. Cohen. It’s wise to note the legally required disclaimer on each product: “These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.”

But even the strong language in this disclaimer — “not intended to diagnose, treat, cure, or prevent” — doesn’t seem to affect how people perceive the marketing claims.

Although multivitamins aren’t helpful, at least they’re not harmful. But the money people spend on them could be better spent on purchasing healthy foods, Dr. Cohen says.

About the Author

Julie Corliss, Executive Editor, Harvard Heart Letter

Julie Corliss is the executive editor of the Harvard Heart Letter. Before working at Harvard, she was a medical writer and editor at HealthNews, a consumer newsletter affiliated with The New England Journal of Medicine. She … See Full Bio View all posts by Julie Corliss

At one time, replacement parts for the eyes must have seemed unimaginable. Nowadays, if the inner lens of the eye becomes clouded by a cataract, a routine surgery to swap it out with a new artificial lens restores vision.

But what happens if the outer lens of the eye (the cornea) becomes damaged or diseased? You can have that replaced, too. “It’s not as common as cataract surgery, but many people get corneal diseases after age 50 and may need a corneal transplant,” says Dr. Nandini Venkateswaran, a corneal and cataract surgeon at Harvard-affiliated Massachusetts Eye and Ear.

More than 49,000 corneal transplants occurred in 2021 in the US, according to the Eye Bank Association of America.

What is the cornea?

The cornea is a dome of clear tissue at the front of each eye, covering the iris and pupil, that acts as a windshield that protects the delicate eye apparatus behind it, and focuses light onto the retina, which sends signals that the brain turns into images (your vision).

You need this combo of windshield and camera lens to focus and see clearly. But many things can go wrong within the five layers of tissue that make up the cornea. That can make it hard to see and rob you of the ability to read, drive, work, and get through other activities in your day.

How does damage to the cornea occur?

It may stem from a number of causes:

• Injuries, such as a fall. “Falls are a big reason for people to come in with acute eye trauma. The cornea can be damaged easily if something pokes it,” Dr. Venkateswaran says.
• Previous eye surgeries. “Especially for adults who’ve had several eye surgeries — such as cataract and glaucoma surgeries — the inner layers of the cornea can become damaged and weakened with age,” she adds.
• Illness. Problems like severe corneal infections, or genetic conditions such as Fuchs’ endothelial dystrophy, can cause vision loss.

What are the options for treating corneal damage?

Cornea treatment depends on the type of problem you have and the extent of the damage. “It’s a stepwise approach. Sometimes wearing a specialty contact lens or using medications can decrease swelling or scarring in the cornea,” Dr. Venkateswaran says.

When damage can’t be repaired, surgeons can replace one or a few layers of the cornea (a partial-thickness transplant), or the whole thing (a full-thickness transplant).

The vast majority of transplants come from donor corneas that are obtained and processed by eye banks throughout the US. In some instances, such as when repeated transplants fail, an artificial cornea is an option. Recovery after corneal surgery can take up to a year.

How long-lasting are corneal transplants?

There’s always a risk that your body will reject a corneal transplant. It happens about a third of the time for full-thickness transplants. It occurs less often for partial-thickness transplants. Preventing rejection requires a lifetime of eye drops.

Still, transplant longevity varies. “I’ve seen transplants from 50 or 60 years ago and now they’re starting to show wear and tear. Other patients, for a variety of reasons — immune system attacks, intolerance to eye drops, or underlying conditions — may only have a transplant for five to 10 years before they need another,” Dr. Venkateswaran explains.

Preventive eye care can help preserve the cornea

It’s crucial to get regular comprehensive eye exams to make sure your corneas and the rest of your eyes are healthy.

The American Academy of Ophthalmology recommends a comprehensive (dilated) eye exam

• at age 40
• every two to four years for people ages 40 to 54
• every one to three years for people ages 55 to 64
• every one to two years for people ages 65 and older.

You’ll need an eye exam more often if you have underlying conditions that increase your risk for eye disease, such as diabetes or a family history of corneal disease.

If you have any vision problems, such as eye pain, redness, blurred vision despite new glasses, or failing eyesight, see an eye doctor.

Fortunately, for people who do experience corneal damage, advances in surgical options are encouraging.

“Corneal transplants are a miracle,” Dr. Venkateswaran says. “I have patients whose quality of life was significantly decreased because they couldn’t see through their cloudy windshield. We can give them sight again, and we have the technology and medications to keep the transplant alive.”

About the Author

Heidi Godman, Executive Editor, Harvard Health Letter

Heidi Godman is the executive editor of the Harvard Health Letter. Before coming to the Health Letter, she was an award-winning television news anchor and medical reporter for 25 years. Heidi was named a journalism fellow … See Full Bio View all posts by Heidi Godman

Active surveillance for prostate cancer has its tradeoffs. Available to men with low- and intermediate-risk prostate cancer, the process entails monitoring a man’s tumor with periodic biopsies and prostate-specific antigen (PSA) tests, and treating only when — or if — the disease shows signs of progression.

Active surveillance allows men to avoid (at least for a while) the side effects of invasive therapies such as surgery or radiation, but men often feel anxious wondering about the state of their cancer as they spend more time untreated. Is there a middle path between not treating the cancer at all and aggressive therapies that might have lasting side effects? Emerging evidence suggests the answer might be yes.

During a newly-published phase 2 clinical trial, researchers evaluated whether a drug called enzalutamide might delay cancer progression among men on active surveillance. Enzalutamide interferes with testosterone, a hormone that drives prostate tumors to grow and spread. Unlike other therapies that block synthesis of the hormone, enzalutamide prevents testosterone from interacting with its cellular receptor.

A total of 227 men were enrolled in the study. The investigators randomized half of them to a year of daily enzalutamide treatment plus active surveillance, and the other half to active surveillance only. After approximately two years of follow-up, the investigators compared findings from the two groups.

The results showed benefits from enzalutamide treatment. Specifically, tumor biopsies revealed evidence of cancer progression in 32 of the treated men, compared to 42 men who did not get the drug. The odds of finding no cancer in at least some biopsy samples were 3.5 times higher in the enzalutamide-treated men. And it took six months longer for PSA levels to rise (suggesting the cancer is growing) in the treated men, compared to men who stayed on active surveillance only.

Enzalutamide was generally well tolerated. The most common side effects were fatigue and breast enlargement, both of which are reversible when men go off treatment.

In an accompanying editorial, Susan Halabi, a statistician who specializes in prostate cancer at Duke University, described the data as encouraging. But Halabi also sounded a cautionary note. Importantly, differences between the two groups were evident only during the first year of follow-up. By the end of the second year, signs of progression in the treated and untreated groups “tended to be very similar,” she wrote, suggesting that enzalutamide is beneficial only for as long as men stay on the drug. Longer studies lasting a decade or more, Halabi added, may be necessary to determine if early enzalutamide therapy changes the course of the disease, such that the need for more invasive treatments among some men can be delayed or prevented.

Dr. Marc Garnick, the Gorman Brothers Professor of Medicine at Harvard Medical School and Beth Israel Deaconess Medical Center, editor of the Harvard Health Publishing Annual Report on Prostate Diseases, and editor in chief of HarvardProstateKnowledge.org, said the study points to a new way of approaching active surveillance, either with enzalutamide or perhaps other drugs. “An option that further decreases the likelihood that men on active surveillance will need radiation or surgery is important to consider,” he says. “This was a pilot study, and now we need longer-term research.”

About the Author

Charlie Schmidt, Editor, Harvard Medical School Annual Report on Prostate Diseases

Charlie Schmidt is an award-winning freelance science writer based in Portland, Maine. In addition to writing for Harvard Health Publishing, Charlie has written for Science magazine, the Journal of the National Cancer Institute, Environmental Health Perspectives, … See Full Bio View all posts by Charlie Schmidt

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