November 21, 2023 dirvel

How — and why — to fit more fiber and fermented food into your meals

A bowl of whole-grain muesli, yogurt, red watermelon, and yellow mango with two little side bowls of nuts and fruit; concept is fiber and fermented foods

An F may mean failure in school, but the letter earns high marks in your diet. The two biggest dietary Fs — fiber and fermented foods — are top priorities to help maintain healthy digestion, and they potentially offer much more. How can you fit these nutrients into meals? Can this help your overall health as well as gut health?

Fiber, fermented foods, and the gut microbiome

The gut microbiome is a composed of bacteria, viruses, fungi, and other microorganisms living in the colon (large intestine). What you eat, the air you breathe, where you live, and many other factors affect the makeup of the gut microbiome. Some experts think of it as a hidden organ because it has a role in many important functions of the body — for example, helping the immune system function optimally, reducing chronic inflammation, keeping intestinal cells healthy, and providing some essential micronutrients that may not be included in a regular diet.

Your gut communicates with your brain through pathways in the gut-brain axis. Changes in the gut microbiome have been linked with mood and mental health disorders, such as depression and anxiety. However, it’s not yet clear that these changes directly cause these types of problems.

We do know that a healthy diet low in processed foods is key to a healthy gut microbiome. And increasing evidence suggests that fiber and fermented foods can play important parts here.

Fiber 101

Fiber’s main job is to make digestion smoother by softening and adding bulk to stool, making it pass quickly through the intestines.

But fiber has other benefits for your microbiome and overall health. A high-fiber diet helps keep body weight under control and lowers LDL (bad) cholesterol levels. Research has found that eating enough fiber reduces the risk of heart disease, type 2 diabetes, and some cancers.

What to know about fiber

There are two types of fiber: insoluble (which helps you feel full and encourages regular bowel movements) and soluble (which helps lower cholesterol and blood sugar). However, recent research suggests people should focus on the total amount of fiber in their diet, rather than type of fiber.

If you’re trying to add more foods with fiber to your diet, make sure you ease into new fiber-rich habits and drink plenty of water. Your digestive system must adapt slowly to avoid gas, bloating, diarrhea, and stomach cramps caused by eating too much too soon. Your body will gradually adjust to increasing fiber after a week or so.

How much fiber do you need?

The fiber formula is 14 grams for every 1,000 calories consumed. Your specific calorie intake can vary depending on your activity levels.

“But instead of tracking daily fiber, focus on adding more servings of fiber-rich foods to your diet,” says Eric Rimm, professor of epidemiology and nutrition at Harvard’s T.H. Chan School of Public Health.

Which foods are high in fiber?

Fruits, vegetables, legumes, nuts, seeds, and whole grains are all high in fiber. The Dietary Guidelines for Americans has a comprehensive list of fiber-rich foods and their calorie counts.

What about over-the-counter fiber supplements that come in capsules, powders that you mix with water, and chewable tablets? “If you have trouble eating enough fiber-rich foods, then these occasionally can be used, and there is no evidence they are harmful,” says Rimm. “But they should not serve as your primary source of dietary fiber.”

Fermented foods 101

Fermented foods contain both prebiotics — ingredients that create healthy changes in the microbiome — and beneficial live bacteria called probiotics. Both prebiotics and probiotics help maintain a healthy gut microbiome.

What to know about fermented foods

Besides helping with digestion and absorbing vital nutrients from food, a healthy gut supports your immune system to help fight infections and protect against inflammation. Some research suggests that certain probiotics help relieve symptoms of gut-related conditions like inflammatory bowel disease and irritable bowel syndrome, though not all experts agree with this.

Many foods that are fermented undergo lacto-fermentation, in which natural bacteria feed on the sugar and starch in the food, creating lactic acid. Not only does this process remove simple sugars, it creates various species of good bacteria, such as Lactobacillus or Bifidobacterium. (Keep in mind that some foods undergo steps that remove probiotics and other healthful microbes, as with beer or wine, or make them inactive, like baking and canning.)

The exact amounts and specific strains of bacteria in fermented foods vary depending on how they are made. In addition to probiotics, fermented foods may contain other valuable nutrients like enzymes, B vitamins, and omega-3 fatty acids.

How often should you eat fermented foods?

There is no recommended daily allowance for prebiotics or probiotics, so it is impossible to know precisely which fermented foods or quantities are best. The general guideline is to add more to your daily diet.

Which fermented foods should you choose?

Fermented foods have a range of tastes and textures because of the particular bacteria they produce during fermentation or that are added to foods. Yogurt is one of the most popular fermented foods (look for the words “live and active cultures” on the label). Still, many options are available if you are not a yogurt fan or want to expand your fermented choices. Kimchi, sauerkraut, kombucha, and pickles are a few examples.

As with fiber, probiotics are also marketed as over-the-counter supplements. However, like all dietary supplements, they do not require FDA approval, so there is no guarantee that the types of bacteria listed on a label can provide the promised benefits — or are even in the bottle. “Therefore, it is best to get your probiotics from fermented foods,” says Rimm.

To learn more about the value of fiber, fermented foods, and a healthy gut microbiome, listen to this episode of the Food, We Need to Talk podcast, “Understanding the Microbiome.”

About the Author

photo of Matthew Solan

Matthew Solan, Executive Editor, Harvard Men's Health Watch

Matthew Solan is the executive editor of Harvard Men’s Health Watch. He previously served as executive editor for UCLA Health’s Healthy Years and as a contributor to Duke Medicine’s Health News and Weill Cornell Medical College’s … See Full Bio View all posts by Matthew Solan

About the Reviewer

photo of Howard E. LeWine, MD

Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing

Dr. Howard LeWine is a practicing internist at Brigham and Women’s Hospital in Boston, Chief Medical Editor at Harvard Health Publishing, and editor in chief of Harvard Men’s Health Watch. See Full Bio View all posts by Howard E. LeWine, MD

September 27, 2023 dirvel

Dupuytren’s contracture of the hand

White and gray 3-D xray illustration showing the bones of the hand against a black background

One of the more unusual conditions affecting the hands and fingers is Dupuytren’s contracture (also called Dupuytren’s disease). Here, one or more fingers become curled, which can make it difficult to pick up or hold objects or perform everyday activities.

Legend says the condition originated with the Vikings of Northern Europe, although this is debated. It was later named after the 19th-century French surgeon Guillaume Dupuytren, who did the first successful operation on the condition. Fast-forward to the 21st century, and Dupuytren’s contracture now affects about one in 20 Americans.

What is Dupuytren’s contracture?

Fascia is a sheet of fibrous tissue beneath the skin of the fingers and the palm. Dupuytren’s contracture is a thickening and shortening of this tissue.

This thickened area begins as a hard lump called a nodule. Over years to decades, it may progress to a thick band called a cord that causes one or more fingers to curl toward the palm and become stuck in a bent position. This can make it difficult to grasp objects, button clothes, use a computer, or perform other daily tasks.

The condition does not always get progressively worse. It may be stable for years or even improve in some people.

Which fingers are most likely to be affected?

The ring and pinky fingers are most often affected. But the condition can strike all fingers and the thumb.

“In about half of cases, the condition can affect both hands,” says Dr. Phillip Blazar, an orthopedic surgeon and Division Chief of Hand and Upper Extremity at Harvard-affiliated Brigham and Women’s Hospital. Fortunately, it rarely causes pain.

What causes Dupuytren’s contracture?

Currently, the cause is unclear. Still, several factors can increase a person’s risk, such as

  • Genetics: This condition is more common in people with Northern European, British Isles, or Scandinavian ancestry.
  • Gender: Men are affected more often than women.
  • Age: The condition often occurs after age 50.
  • Family history of the disease.

People with diabetes and seizure disorders are also more likely to have Dupuytren’s. The condition may appear and/or worsen after trauma to the hand.

How is Dupuytren’s contracture treated?

Although there is no cure, treatments and occupational or physical therapy can help address symptoms and improve finger mobility. “Many people who have mild cases of Dupuytren’s find it has little impact on their ability to use their hands,” says Dr. Blazar.

However, moderate or severe cases can interfere with hand function. It’s possible to restore normal finger motion with nonsurgical treatments, such as:

  • Collagenase injection. This procedure is done in the doctor’s office. An enzyme called collagenase is injected into the cords of your hand, which breaks down and dissolves the thickened tissue. At a follow-up visit, your doctor will give you local anesthesia and then snap the cords by manipulating and straightening your fingers in the direction in which they are unable to move.
  • Needle aponeurotomy. This in-office procedure involves passing a hypodermic needle back and forth through the restrictive cords to weaken and break them.

“Your hand surgeon will discuss both treatment options to determine which is best for your situation,” says Dr. Blazar. “There are also some variations in the anatomy of the disease which may make one treatment or the other less favorable for a particular person or finger.” Both of these treatments don’t remove the cords, and the condition can return and require additional treatment.

What about surgical treatment?

If nonsurgical treatment does not relieve symptoms or you have a severe condition, surgery may be recommended. Surgical approaches include:

  • Fasciotomy. An incision is made in your palm to divide the thickened tissue in the cord.
  • Subtotal palmar fasciectomy. A zigzag incision is made along the creases in the hand to remove the abnormal tissue and cord. Occasionally, a skin graft may be needed to help the wound heal.

You wear a splint on the repaired hand during recovery. People should expect some pain, stiffness, and swelling afterward. The length of recovery varies for each individual, and also with how many fingers were operated on and which ones.

“Most people largely recover by three months, but some may not feel fully recovered for quite a bit longer,” says Dr. Blazar. Hand therapists can also help with strength and flexibility exercises to speed recovery.

Most people’s fingers move better after surgery. However, as with nonsurgical treatments, the contracture can come back, so some people may need additional surgery later on.

About the Author

photo of Matthew Solan

Matthew Solan, Executive Editor, Harvard Men's Health Watch

Matthew Solan is the executive editor of Harvard Men’s Health Watch. He previously served as executive editor for UCLA Health’s Healthy Years and as a contributor to Duke Medicine’s Health News and Weill Cornell Medical College’s … See Full Bio View all posts by Matthew Solan

About the Reviewer

photo of Howard E. LeWine, MD

Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing

Dr. Howard LeWine is a practicing internist at Brigham and Women’s Hospital in Boston, Chief Medical Editor at Harvard Health Publishing, and editor in chief of Harvard Men’s Health Watch. See Full Bio View all posts by Howard E. LeWine, MD

September 15, 2023 dirvel

PTSD: How is treatment changing?

A while spiral notebook with words related to PTSD written on it, such as depression, fear, anxiety, negative thoughts); desk also has pen and coffee cup

Over the course of a lifetime, as many as seven in 10 adults in the United States will directly experience or witness harrowing events. These include gun violence, car accidents, and other personal trauma; natural or human-made disasters, such as Hurricane Katrina and the 9/11 terrorist attacks; and military combat. And some — though not all — will experience post-traumatic stress disorder, or PTSD.

New guidelines released in 2024 can help guide effective treatment.

What is PTSD?

PTSD is a potentially debilitating mental health condition. It’s marked by recurrent, frightening episodes during which a person relives a traumatic event.

After a disturbing event, it’s normal to have upsetting memories, feel on edge, and have trouble sleeping. For most people, these symptoms fade over time. But when certain symptoms persist for more than a month, a person may be experiencing PTSD.

These symptoms include

  • recurring nightmares or intrusive thoughts about the event
  • feeling emotionally numb and disconnected
  • withdrawing from people and certain situations
  • being jumpy and on guard.

The National Center for PTSD offers a brief self-screening test online, which can help you decide whether to seek more information and help.

Who is more likely to experience PTSD?

Not everyone who experiences violence, disasters, and other upsetting events goes on to develop PTSD. However, military personnel exposed to combat in a war zone are especially vulnerable. About 11% to 20% of veterans who served in Iraq or Afghanistan have PTSD, according to the National Center for PTSD.

What about people who were not in the military? Within the general population, estimates suggest PTSD occurs in 4% of men and 8% of women — a difference at least partly related to the fact that women are more likely to experience sexual assault.

What are the new guidelines for PTSD treatment?

Experts from the U.S. Department of Veterans Affairs and Department of Defense collaborated on new guidelines for treating PTSD. They detailed the evidence both for and against specific therapies for PTSD.

Their findings apply to civilian and military personnel alike, says Dr. Sofia Matta, a psychiatrist at Harvard-affiliated Massachusetts General Hospital and senior director of medical services at Home Base, a nonprofit organization that provides care for veterans, service members, and their families.

The circle of care is widely drawn for good reason. “It’s important to recognize that PTSD doesn’t just affect the person who is suffering but also their families and sometimes, their entire community,” Dr. Matta says. The rise in mass shootings in public places and the aftermath of these events are a grim reminder of this reality, she adds.

Which treatment approaches are most effective for PTSD?

The new guidelines looked at psychotherapy, medications, nondrug therapies. Psychotherapy, sometimes paired with certain medicines, emerged as the most effective approach.

The experts also recommended not taking certain drugs due to lack of evidence or possible harm.

Which psychotherapies are recommended for PTSD?

The recommended treatment for PTSD, psychotherapy, is more effective than medication. It also has fewer adverse side effects and people prefer it, according to the guidelines.

Which type of psychotherapy can help? Importantly, the most effective therapies for people with PTSD differ from those for people with other mental health issues, says Dr. Matta.

Both cognitive processing therapy and prolonged exposure therapy were effective. These two therapies teach people how to evaluate and reframe the upsetting thoughts stemming from the traumatic experience. The guidelines also recommend mindfulness-based stress reduction, an eight-week program that includes meditation, body scanning, and simple yoga stretches.

Which medications are recommended for PTSD?

Some people with severe symptoms need medication to feel well enough to participate in therapy. “People with PTSD often don’t sleep well due to insomnia and nightmares, and the resulting fatigue makes it hard to pay attention and concentrate,” says Dr. Matta.

Three medicines commonly prescribed for depression and anxiety — paroxetine (Paxil), sertraline (Zoloft), and venlafaxine (Effexor) — are recommended. Prazosin (Minipress) may help people with nightmares, but the evidence is weak.

Which medications are not recommended for PTSD?

The guidelines strongly recommended not taking benzodiazepines (anti-anxiety drugs often taken for sleep). Benzodiazepines such as alprazolam (Xanax) and clonazepam (Klonopin) offer no proven benefits for people with PTSD. They have several potential harms, including negative cognitive changes and decreased effectiveness of PTSD psychotherapies.

What about cannabis, psychedelics, and brain stimulation therapies?

Right now, evidence doesn’t support the idea that cannabis helps ease PTSD symptoms. And there are possible serious side effects from the drug, such as cannabis hyperemesis syndrome (severe vomiting related to long-term cannabis use).

There isn’t enough evidence to recommend for or against psychedelic-assisted therapies such as psilocybin (magic mushrooms) and MDMA (ecstasy). “Because these potential therapies are illegal under federal law, the barriers for conducting research on them are very high,” says Dr. Matta. However, recent legislative reforms may make such studies more feasible.

Likewise, the evidence is mixed for a wide range of other nondrug therapies, such as brain stimulation therapies like repetitive transcranial magnetic stimulation or transcranial direct current stimulation.

About the Author

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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

About the Reviewer

photo of Howard E. LeWine, MD

Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing

Dr. Howard LeWine is a practicing internist at Brigham and Women’s Hospital in Boston, Chief Medical Editor at Harvard Health Publishing, and editor in chief of Harvard Men’s Health Watch. See Full Bio View all posts by Howard E. LeWine, MD

August 28, 2023 dirvel

Wildfires: How to cope when smoke affects air quality and health

A barge on a New York City river and skyscrapers, all blurred by orange-gray smoke from massive wildfires

As wildfires become more frequent due to climate change and drier conditions, more of us and more of our communities are at risk for harm. Here is information to help you prepare and protect yourself and your family.

How does wildfire smoke affect air quality?

Wildfire smoke contributes greatly to poor air quality. Just like fossil fuel pollution from burning coal, oil, and gas, wildfires create hazardous gases and tiny particles of varying sizes (known as particulate matter, or PM10, PM2.5, PM0.1) that are harmful to breathe. Wildfire smoke also contains other toxins that come from burning buildings and chemical storage.

The smoke can travel to distant regions, carried by weather patterns and jet streams.

How does wildfire smoke affect our health?

The small particles in wildfire smoke are the most worrisome to our health. When we breathe them in, these particles can travel deep into the lungs and sometimes into the bloodstream.

The health effects of wildfire smoke include eye irritation, coughing, wheezing, and difficulty breathing. The smoke may also increase risk for respiratory infections like COVID-19. Other possible serious health effects include heart failure, heart attacks, and strokes.

Who needs to be especially careful?

Those most at risk from wildfire smoke include children, older adults, outdoor workers, and anyone who is pregnant or who has heart or lung conditions.

If you have a chronic health condition, talk to your doctor about how the smoke might affect you. Find out what symptoms should prompt medical attention or adjustment of your medications. This is especially important if you have lung problems or heart problems.

What can you do to prepare for wildfire emergencies?

If you live in an area threatened by wildfires, or where heat and dry conditions make them more likely to occur:

  • Create an evacuation plan for your family before a wildfire occurs.
  • Make sure that you have several days on hand of medications, water, and food that doesn't need to be cooked. This will help if you need to leave suddenly due to a wildfire or another natural disaster.
  • Regularly check this fire and smoke map, which shows current wildfire conditions and has links to state advisories.
  • Follow alerts from local officials if you are in the region of an active fire.

What steps can you take to lower health risks during poor air quality days?

These six tips can help you stay healthy during wildfire smoke advisories and at other times when air quality is poor:

  • Stay aware of air quality. AirNow.gov shares real-time air quality risk category for your area accompanied by activity guidance. When recommended, stay indoors, close doors, windows, and any outdoor air intake vents.
  • Consider buying an air purifier. This is also important even when there are no regional wildfires if you live in a building that is in poor condition. See my prior post for tips about pollution and air purifiers. The EPA recommends avoiding air cleaners that generate ozone, which is also a pollutant.
  • Understand your HVAC system if you have one. The quality and cleanliness of your filters counts, so choose high-efficiency filters if possible, and replace these as needed. It's also important to know if your system has outdoor air intake vents.
  • Avoid creating indoor pollution. That means no smoking, no vacuuming, and no burning of products like candles or incense. Avoid frying foods or using gas stoves, especially if your stove is not well ventilated.
  • Make a "clean room." Choose a room with fewer doors and windows. Run an air purifier that is the appropriate size for this room, especially if you are not using central AC to keep cool.
  • Minimize outdoor time and wear a mask outside. Again, ensuring that you have several days of medications and food that doesn't need to be cooked will help. If you must go outdoors, minimize time and level of activity. A well-fitted N95 or KN95 mask or P100 respirator can help keep you from breathing in small particles floating in smoky air (note: automatic PDF download).

About the Author

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Wynne Armand, MD, Contributor

Dr. Wynne Armand is a physician at Massachusetts General Hospital (MGH), where she provides primary care; an assistant professor in medicine at Harvard Medical School; and associate director of the MGH Center for the Environment and … See Full Bio View all posts by Wynne Armand, MD

August 15, 2023 dirvel

A hot weather plan is essential to staying healthy

Computer-generated image of orange, yellow, red heat wave halo surrounding thermother with high temperature; concept is dangerous heat

Here’s a new fact about spring, summer, fall, and sometimes even winter: now that climate change has blurred seasonal boundaries, sizzling heat may be on the way, or currently blanketing your community.

High temperatures stress the body, leading to thousands of heat-related illnesses and deaths every year in the US. Creating a personal heat plan can help you stay safe when the heat index soars.

Caleb Dresser, MD, MPH, is the health care solutions lead for C-CHANGE, the Center for Climate Health and the Global Environment at the Harvard T.H. Chan School of Public Health, and an emergency medicine doctor at Harvard-affiliated Beth Israel Deaconess Medical Center. Below we interview him about who, how, and why heat harms. Then we’ll help you create your personal heat safety plan.

Interview edited for clarity

Who is especially vulnerable during hot weather?

High temperatures can affect anyone. But some people — children, outdoor workers, people who are pregnant or have health problems or disabilities, and older people — are more likely to experience harm when temperatures rise. For example:

  • Young children, especially babies, have less physical capacity to deal with very high temperatures.
  • People working outdoors may not have access to shade and could be performing physically intensive labor. They need adequate hydration, adequate breaks, and access to a cool space during break time, as OSHA guidelines spell out.
  • People with chronic medical conditions, such as kidney disease or heart disease, may have difficulty adapting physiologically to hot weather, or may be more susceptible to its health impacts.
  • And some people living with disabilities or certain neurological conditions may have difficulty with thermoregulation — that is, controlling the temperature of their bodies — or may not be able to take actions that keep them safe, such as taking off layers or moving to a cool area.

Which weather patterns create dangerous levels of heat?

Dangerous heat is the result of both high temperatures and high humidity, which interfere with our ability to cool off by sweating. In dry areas, extremely hot temperatures can be dangerous on their own.

Danger zones vary across the United States and around the world. But hospital use and deaths rise once we get above threshold temperatures. The threshold varies in different places depending on whether bodies, cultures, and architecture are adapted to heat.

For example, here in New England, where some people (particularly those of limited means) may not have access to air conditioning, we see increases in healthcare use and deaths at a lower temperature than in the American South, where people and organizations may be more used to dealing with hot weather.

When does hot weather become dangerous to our health?

Risk goes up the longer hot weather sticks around.

One hot day can put some people at risk. A stretch of several hot days in a row during a heat wave is particularly dangerous because it can overwhelm people’s ability to adapt. Eventually people run out of physiological reserves, leading to greater health harms and greater need for medical care.

Surprisingly, spring and early summer are particularly dangerous times because people and organizations aren’t as prepared for hot weather.

How to create your personal heat safety plan

Five key points to help you create a personal heat plan are below. Americares offers further information through heat tip sheets developed with the Harvard C-CHANGE team that are tailored to people in different health circumstances.

Planning is important because intense heat is occurring more often: a Climate Central analysis found 21 additional risky heat days, on average, for 232 out of 249 locations between 1970 and 2022.

  • Stay ahead of hot weather. Check apps, websites, TV, or radio for updates on weather today and in coming days. If local weather alerts are available by phone or text, sign up.
  • Have a cooling plan. When temperatures soar, you need to spend as much time as possible in cool spaces. Plan options if your home is likely to be too hot and unsafe to stay in. You may be able to stay with a neighbor or family member who has air conditioning until a heat wave passes. Many cities and towns have neighborhood splash pads for children, and open cooling centers or air-conditioned libraries, public buildings, or community centers to everyone — sometimes even overnight. Spending time in air-conditioned businesses or malls, or in a shady green space like a park, may help too.
  • Sip plenty of fluids. Water is the best choice. Skip sugary drinks and avoid caffeine or alcohol.
  • Use fans correctly. Fans help if surrounding air is relatively cool. If air temperatures are very high, it’s important to dampen your clothes or skin to help keep your body from overheating, and move to a cooler location, if possible.
  • Know your personal risks and the signs of heat-related illness. If you have health problems or disabilities, or take certain medicines such as diuretics, talk to your doctor about the best ways for you to cope with heat. It’s also essential to know the signs of heat-related illnesses, which range from heat rash and sunburn to heat cramps, heat exhaustion, and heat stroke. This chart from the Centers for Disease Control and Prevention describes the signs to look for and what you can do, particularly when heat becomes an emergency.

About the Author

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Francesca Coltrera, Editor, Harvard Health Blog

Francesca Coltrera is editor of the Harvard Health Blog, and a senior content writer and editor for Harvard Health Publishing. She is an award-winning medical writer and co-author of Living Through Breast Cancer and The Breast … See Full Bio View all posts by Francesca Coltrera

About the Reviewer

photo of Howard E. LeWine, MD

Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing

Dr. Howard LeWine is a practicing internist at Brigham and Women’s Hospital in Boston, Chief Medical Editor at Harvard Health Publishing, and editor in chief of Harvard Men’s Health Watch. See Full Bio View all posts by Howard E. LeWine, MD

August 2, 2023 dirvel

Why play? Early games build bonds and brain

Want your child to grow up healthy, happy, smart, capable, and resilient? Play with them. Infants and toddlers thrive on playful games that change as they grow.

Why does play matter during the first few years of life?

More than a million new nerve connections are made in the brain in the first few years of life. And pruning of these neural connections makes them more efficient. These processes literally build the brain and help guide how it functions for the rest of that child’s life. While biology — particularly genetics — affects this, so does a child’s environment and experiences.

Babies and children thrive with responsive caregiving. Serve and return, a term used by the Harvard Center on the Developing Child, describes this well: back-and-forth interactions, in which the child and caregiver react to and interact with each other in a loving, nurturing way, are the building blocks of a healthy brain and a happy child, who will have a better chance of growing into a healthy, happy, competent, and successful adult.

Play is one of the best ways to do responsive caregiving. To maximize the benefits of play:

  • Bring your full attention. Put the phone down, don’t multitask.
  • Be reciprocal. That’s the “serve and return” part. Even little babies can interact with their caregivers, and that’s what you want to encourage. It doesn’t have to be reciprocal in an equal way — you might be talking in sentences while your baby is just smiling or cooing — but the idea is to build responsiveness into the play.
  • Be attuned to developmental stages. That way your child can fully engage — and you can encourage their development as well.

Great games to play with infants: 6 to 9 months

The Center for the Developing Child has some great ideas and handouts for parents about specific games to play with their children at different ages.

6-month-olds and 9-month-olds are learning imitation and other building blocks of language. They are also starting to learn movement and explore the world around them.

Here are some play ideas for this age group:

  • Play peek-a-boo or patty-cake.
  • Play games of hiding toys under a blanket or another toy, and then “find” them, or let the baby find them.
  • Have back-and-forth conversations. The baby’s contribution might just be a “ma” or “ba” sound. You can make the same sound back, or pretend that your baby is saying something (“You don’t say! Really? Tell me more!”).
  • Play imitation games: if your baby sticks out their tongue, you do it too, for example. Older babies will start to be able to imitate things like clapping or banging, and love when grownups do that with them.
  • Sing songs that involve movement, like “Itsy Bitsy Spider” or “Trot, Trot to Boston” with words and motions.
  • Play simple games with objects, like putting toys into a bucket and taking them out, or dropping them and saying “boom!”

Great games to play with toddlers

Between 12 months and 18 months, young toddlers are gaining more language and movement skills, and love to imitate. You can:

  • Play with blocks, building simple things and knocking them down together.
  • Do imaginative play with dolls or stuffed animals, or pretend phone calls.
  • Use pillows and blankets to build little forts and places to climb and play.
  • Play some rudimentary hide-and-seek, like hiding yourself under a blanket next to the baby.
  • Continue singing songs that involve movement and interaction, like “If You’re Happy And You Know It.”
  • Go on outings and explore the world together. Even just going to the grocery store can be an adventure for a baby. Narrate everything. Don’t worry about using words your baby doesn’t understand; eventually they will, and hearing lots of different words is good for them.

Older toddlers, who are 2 or 3 years old, are able to do more complicated versions of these games. They can do matching, sorting, and counting games, as well as imitation and movement games like “follow the leader” (you can get quite creative and silly with that one).

As much as you can, give yourself over to play and have fun. Work and chores can wait, or you can actually involve young children in chores, making that more fun for both of you. Checking social media can definitely wait.

Playing with your child is an investment in your child’s future — and a great way to build your relationship and make both of you happy.

About the Author

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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

July 27, 2023 dirvel

A bird flu primer: What to know and do

A weathered sign with red background and big white and black letters spelling out bird flu

A bird flu strain that began circulating in 2020 continues to evolve globally and locally within the United States. If you’re wondering what this means, understanding the basics — what bird flu is, how it spreads, whether foods are safe, and prevention tips — can help. More information will come in as scientists learn more, so stay tuned.

1. What is bird flu and how does it spread?

Bird flu, or avian flu, is a naturally occurring illness. Just as certain flu viruses spread among humans, Type A influenza viruses often spread among wild birds. The strain of virus circulating now is H5N1, named for two proteins on its surface.

Avian flu infections are highly contagious. Infection often spreads first among wild water birds, such as ducks, geese, and gulls, and shore birds, such as plovers and sandpipers. The viruses are carried in their intestines and respiratory tract and shed in saliva, mucus, and feces. Wild birds can easily infect domestic poultry, such as chickens, turkeys, and ducks.

Some bird species, including ducks, may carry and spread infection without appearing sick. Domestic flocks are more likely to sicken and possibly die from bird flus. However, not all avian flu viruses are equally harmful:

  • Low pathogenic avian influenza (LPAI) may cause no signs of illness, or signs of mild illness like fewer eggs or ruffled feathers in domestic poultry.
  • Highly pathogenic avian influenza (HPAI) causes more severe illness and high rates of death in infected poultry. The current H5N1 virus is considered an HPAI.

2. Can humans get bird flu?

Yes, though this doesn’t usually happen.

When flu viruses mutate, they may be able to move from their original hosts — birds in this case — to humans and other animals. As of early April 2024, only two cases of bird flu in humans had been reported in the US since 2022. In May, two more cases were reported. Newer case numbers of bird flu will continue to be reported by the CDC, which offers weekly snapshots of influenza in the US.

The virus may be introduced into the body through the eyes, nose, or mouth. For example, a person may inhale viral particles in the air (droplets, tiny aerosolized particles, or possibly in dust). Or they might touch a surface contaminated by the virus, then touch their eyes or nose. Bird flu in humans typically causes symptoms similar to seasonal flu, such as fever, runny nose, and body aches.

3. Which animals have been affected by bird flu?

A surprisingly long list of animals affected by the current H5NI bird flu infection includes:

  • wild birds, chickens, ducks, geese, and other domestic and commercial poultry in 48 states and more than 500 countries
  • livestock, such as dairy cows in nine states at this writing, and other farm animals
  • marine animals, such as seals, sea lions, and even dolphins
  • wild animals, such as foxes, skunks, and racoons, and some domestic animals, such as farm cats.

4. Why are experts concerned about this bird flu outbreak?

It might seem odd that there’s been so much concern and news coverage about bird flu lately. After all, bird flu has been around for many years. We’ve long known it sometimes infects nonbird animal species, including humans.

But the current outbreak is unique and worrisome for several reasons:

  • Fast, far-reaching spread. The virus has been found throughout the US, Europe, the Middle East, Southeast Asia, multiple sub-Saharan African countries, and even Antarctica.
  • Many species have been infected. Previously uninfected species have been affected, including animals in our food supply.
  • Economic impact. If large numbers of beef and dairy cows and chickens sicken or must be culled (killed) to contain outbreaks, this could have a major economic impact on farmers, agriculture businesses, and affected countries’ economies. This could also mean higher prices at the grocery store.
  • Opportunities for exposure. Though only two human infections were reported in the US in recent years — both in people working with animals — the more exposure humans have to bird flu, the more chances the virus has to develop mutations that allow easier spread to humans.
  • Potential for fatalities. Severe strains of bird flu have led to H5N1 infections in nearly 900 people in 23 countries since 2003. More than half of these reported cases were fatal. Keep in mind that the math isn’t straightforward. It’s likely that many more cases of bird flu in humans occurred, yet people experiencing few or no symptoms or those not tested weren’t counted, so lethality is likely overestimated.
  • New mutations. It’s rare, but possible: If this H5N1 bird flu develops mutations that enable efficient person-to-person spread, bird flu could become the next human pandemic.

5. Are milk, beef, chicken, and the rest of our food supply safe?

Public health officials emphasize that the food supply is safe.

But concern has understandably run high since the discovery that this outbreak has spread from birds to dairy cows for the first time. More alarming? A study found fragments of bird flu DNA — which is not the same as live virus — in 20% of commercially available milk in the US.

So far, there’s been no indication that bird flu found in pasteurized milk, beef, or other common foods can cause human illness. Even if live bird flu virus got into the milk supply, studies show that routine pasteurization would kill it. Initial tests did not find the virus in ground beef.

Of course, if you are particularly concerned, you could avoid foods and beverages that come from animals affected by bird flu. For example, you could switch to oat milk or almond milk, even though there’s no convincing scientific justification to do so now.

6. What if you have pets or work with animals?

Bird flu rarely spreads to pets. While that’s good news, your pets could have exposure to animals infected with bird flu, such as through eating or playing with a dead bird. So, it’s safest to limit your pet’s opportunities to interact with potentially infected animals.

If you work with animals, especially birds or livestock, or hunt, the Centers for Disease Control and Prevention (CDC) recommends precautions to minimize your exposure to bird flu.

7. What else can you do to stay safe?

The CDC recommends everyone take steps to avoid exposure to bird flu, including:

  • Avoid contact with sick or dead animals and keep pets away from them.
  • Avoid animal feces that may be contaminated by birds or bird droppings, as might be common on a farm.
  • Do not prepare or eat raw or undercooked food.
  • Do not drink raw (unpasteurized) milk or eat raw milk cheese or raw or undercooked foods from animals suspected of having bird flu infection.
  • Wear personal protective equipment (PPE), such as safety goggles, gloves, and an N95 face mask, when working near sick or dead animals or their feces.

Right now, available evidence doesn’t support more dramatic preventive measures, such as switching to an all-plant diet.

8. Is there any good news about bird flu?

Despite all the worrisome news about bird flu, this recent outbreak may wind up posing little threat to human health. Virus strains may mutate to spread less efficiently or to be less deadly. Efforts are underway to contain the spread of bird flu to humans, including removing sick or exposed animals from the food supply and increased testing of dairy cattle before transport across state lines.

And there is other encouraging news:

  • Some birds appear to be developing immunity to the virus. This could reduce the chances of continued spread between birds and other animals.
  • Developing a vaccine to protect cattle from bird flu may be possible (though it’s unclear if this approach will be successful).
  • If spread to humans does occur, genetic tests suggest available antiviral medicines could help treat people.
  • So far, human-to-human transmission has not been detected. That makes it less likely that the H5N1 bird flu will become the next pandemic.
  • And if human infections with bird flu did become more common, researchers are working on human vaccines against bird flu using virus strains that match well with those causing the current outbreak.

9. How worried should you be about bird flu?

Though there’s much we don’t know, this much seems certain: bird flu will continue to change and pose challenges for farmers and health experts to stay ahead of it. So far, public health experts believe that bird flu poses little health risk to the general public.

So, it’s not time to panic about bird flu. But it is a good idea to take common sense steps to avoid exposure and stay current on related news.

For updated information in the US, check the CDC website .

About the Authors

photo of Robert H. Shmerling, MD

Robert H. Shmerling, MD, Senior Faculty Editor, Harvard Health Publishing; Editorial Advisory Board Member, 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 photo of Francesca Coltrera

Francesca Coltrera, Editor, Harvard Health Blog

Francesca Coltrera is editor of the Harvard Health Blog, and a senior content writer and editor for Harvard Health Publishing. She is an award-winning medical writer and co-author of Living Through Breast Cancer and The Breast … See Full Bio View all posts by Francesca Coltrera

About the Reviewer

photo of John Ross, MD, FIDSA

John Ross, MD, FIDSA, Contributor; Editorial Advisory Board Member, Harvard Health Publishing

Dr. John Ross is an assistant professor of medicine at Harvard Medical School. He is board certified in internal medicine and infectious diseases, and practices hospital medicine at Brigham and Women’s Hospital. He is the author … See Full Bio View all posts by John Ross, MD, FIDSA

July 8, 2023 dirvel

Tick season is expanding: Protect yourself against Lyme disease

A black-legged tick on the tip of a pencil

In parts of the United States and Canada, warming temperatures driven by climate change may be contributing to a rise in tick-borne illnesses. Ticks are now thriving in a wider geographic range, and appearing earlier and sticking around later in the shoulder seasons of spring and fall. That means we need to stay vigilant about protecting ourselves against ticks that cause Lyme disease and other illnesses — even during winter months in many warmer states and provinces.

Here’s a timely reminder about why preventing Lyme disease is important, and a refresher on steps you can take to avoid tick bites.

What are the symptoms of Lyme disease?

Lyme disease is best known for its classic symptom, a bull’s-eye red rash that appears after a bite from an infected tick (scroll down to see photos of classic and non-classic rashes). However, 20% to 30% of people do not develop a rash. And a rash can be easy to miss because ticks tend to bite in dark body folds such as the groin, armpit, behind the ears, or on the scalp. Some people have flulike symptoms such as a headache, fever, chills, fatigue, and aching joints. So if you notice a rash or have these symptoms, call your doctor for advice. At this stage, prompt antibiotic treatment can wipe out the bacterial infection.

When people don’t receive treatment because they didn’t see the rash or didn’t have other early symptoms, the bacteria can spread to different parts of the body. Not only can the bacteria itself cause problems, but the body’s immune system can over-respond to the infection. Either process, or sometimes both, may harm joints, the heart, and/or the nervous system. And some people treated for any stage of Lyme disease develop post-Lyme disease syndrome, which can cause a range of debilitating symptoms that include fatigue, brain fog, and depression.

How to avoid getting Lyme disease

Preventing tick bites is the best way to avoid Lyme disease and other tick-borne illnesses. Blacklegged ticks (also called deer ticks) may be infected with the bacteria that causes Lyme disease. If you live in one of the areas where the incidence of Lyme disease is high, these steps can help.

Know where ticks are likely lurking. Ticks usually crawl up from leaves or blades of grass on the ground to the legs. So be extra careful when walking through fields or meadows and on hikes where you may brush up against bushes, leaves, or trees. Try to walk on well-cleared paths.

Wear protective clothing. Long pants tucked into socks is the best way to keep ticks from crawling up under the pant leg. Lighter-colored clothing can make ticks easier to see.

Use repellents. You can buy clothing that’s pretreated with the insecticide permethrin (which repels ticks). Or you can spray your own clothes and shoes; just be sure to follow the directions carefully. On all exposed skin, use a product that contains DEET, picaridin, oil of lemon eucalyptus (OLE), IR3535, para-menthane-diol (PMD), or 2-undecanone. This search tool from the EPA can help you find a product best suited for your needs. Pay attention to the concentration of active ingredients: for example, at least 20% but not more than 50% with DEET; between 5% to 20% with picaridin; and 10% to 30% with oil of lemon eucalyptus. Many products come in pump spray bottles or as sticks or wipes, which may make them easier to apply where needed.

Get a tick check. After spending time in tick-infested areas, ask a partner to check you for ticks in areas on your body that you can’t see very well. The common bite areas are the back of the knee, the groin, under the arms, under the breasts in women, behind the ears, and at the back of the neck. The tick species that transmits Lyme disease is about the size of a sesame seed. Note that a tick has to be attached to your skin for 24 to 36 hours for it to transmit enough bacteria to give you the disease.

For more information about preventing Lyme disease or living with it, visit the Harvard Health Publishing Lyme Wellness Initiative.

About the Author

photo of Julie Corliss

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

About the Reviewer

photo of Howard E. LeWine, MD

Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing

Dr. Howard LeWine is a practicing internist at Brigham and Women’s Hospital in Boston, Chief Medical Editor at Harvard Health Publishing, and editor in chief of Harvard Men’s Health Watch. See Full Bio View all posts by Howard E. LeWine, MD