Archives December 2023

Shining light on night blindness

A dangerously blurry view of cars, streetlights, headlights through a car window at night; concept is night blindness

Animals renowned for their outstanding night vision include owls, cats, tarsiers (a tiny primate in Southeast Asia) — and even the dung beetle.

But humans? Not so much.

Over time, many people suffer from night blindness, also known as nyctalopia. This condition makes seeing in dim or dark settings difficult because your eyes cannot adjust to changes in brightness or detect light.

What are the dangers for those experiencing night blindness?

Night blindness is especially problematic and dangerous when driving. Your eyes cannot adjust between darkness and the headlights of oncoming vehicles, other cars may appear out of focus, and your depth perception becomes impaired, which makes it difficult to judge distances.

Night blindness also may affect your sight at home by making it hard for your vision to quickly adjust to a dark room after turning off the lights. “This can cause people to bump into furniture or trip and suffer an injury,” says Dr. Isabel Deakins, an optometrist with Harvard-affiliated Massachusetts Eye and Ear.

What happens in the eye to create night blindness?

The ability to see in low-light conditions involves two structures in the eye: the retina and the iris.

The retina, located in the back of the eye, contains two types of light-detecting cells called cones and rods. The cones handle color vision and fine details while the rods manage vision in dim light.

The iris is the colored part of your eye. It contains muscles that widen or narrow the opening of your pupil to adjust how much light can enter your eyes.

If your irises don’t properly react, the pupils can dilate and let in too much light, which causes light sensitivity and makes it hard to see in bright light. Or your pupils may remain too small and not allow in enough light, making it tough to see in low light.

What causes night blindness?

Night blindness is not a disease but a symptom of other conditions. “It’s like having a bruise on your body. Something else causes it,” says Dr. Deakins.

Several conditions can cause night blindness. For instance, medications, such as antidepressants, antihistamines, and antipsychotics, can affect pupil size and how much light enters the eye.

Eye conditions that can cause night blindness include:

  • glaucoma, a disease that damages the eye’s optic nerves and blood vessels
  • cataracts, cloudy areas in the lens that distort or block the passage of light through the lens
  • dry eye syndrome.

However, one issue that raises the risk of night blindness that you can’t control is age. “Our eyes react more slowly to light changes as we age, and vision naturally declines over time,” says Dr. Deakins.  “The number of rods in our eyes diminish, pupils get smaller, and the muscles of the irises weaken.”

What helps if you have night blindness?

If you notice any signs of night blindness, avoid driving and get checked by an eye care specialist like an optometrist or ophthalmologist. An eye exam can determine if your eyeglass prescription needs to be updated.

“Often, a prescription change is enough to reduce glare when driving at night," says Dr. Deakins. “You may even need separate glasses with a stronger eye prescription that you wear only when driving at night.”

Adding an anti-reflective coating to your lens may help to cut down on the glare of the headlights of an oncoming car. However, skip the over-the-counter polarized driving glasses sold at many drug stores. "These may help cut down on glare, but they don't address the causes of night blindness," says Dr. Deakins.

An eye exam also will identify glaucoma or cataracts, which can be treated. Glaucoma treatments include eyedrops, laser treatment, or surgery. Cataracts are corrected with surgery to replace the clouded lens with an artificial one. Your eye care specialist can also help identify dry eye and recommend treatment.

Ask your primary care clinician or a pharmacist if any medications that you take may cause night blindness. If so, it may be possible to adjust the dose or switch to another drug.

Three more ways to make night driving safer

You also can take steps to make night driving safer. For example:

  • Wash the lenses of your glasses regularly. And take them to an optician to buff out minor scratches.
  • Keep both sides of your front and rear car windshields clean so that you can see as clearly as possible.
  • Dim your dashboard lights, which cause glare, and use the night setting on your rearview mirror.

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

Ever read your medical record? Here’s why you should

photo of a female doctor conferring with a teen female patient in an exam room, the younger woman is sitting on the exam table and the doctor is holding a tablet and showing it to her

Do you ever read the notes written by your doctor or health practitioner during a medical visit? If not, you might want to check them out. Usually, these medical notes are full of helpful insights about your health and reminders of recommendations discussed. And there’s medicalese, of course: hard-to-pronounce illnesses, medications, and technical terms.

But you may be surprised to see incorrect information or unexpected language, tone, or even innuendo. Was your past medical history really that “unremarkable”? Did you actually “deny” drinking alcohol? Did the note describe you as “unreliable”?

Here’s how to decipher unfamiliar lingo, understand some surprising descriptions, and flag any errors you find.

What’s in a medical note?

A standard medical note has several sections. These include

  • a description of current symptoms
  • past medical problems
  • a list of medications taken
  • family medical history
  • social habits such as smoking, drinking alcohol, or drug use
  • details of the physical examination
  • test results
  • a discussion of the big picture, along with recommendations for further evaluation or treatment.

Notes tend to be more complete for a new patient or annual exam. Follow-up notes may not cover all of these points.

What’s potentially confusing about medical notes?

Most medical notes aren’t written using plain language because they aren’t intended primarily for a nonmedical audience. So it’s common to run across:

  • Medical jargon: You had an upset stomach and a fever. Doctors may say “dyspepsia” (upset stomach) and “febrile” (fever).
  • Complicated disease names: Ever heard of “multicentric reticulohistiocytosis” or “progressive multifocal leukoencephalopathy?” These are just two of thousands of examples.
  • Use of common language in uncommon ways: For example, your medical history might be called “unremarkable” and test results called "within normal limits” rather than “normal.”
  • Abbreviations: You might see “VSS” and “RRR,” meaning “vital signs stable” with a pulse that has a “regular rate and rhythm.”

If you’re having trouble deciphering a note or understanding your health issues, tests, and recommendations, check in with your doctor’s office for clarifications. The more you understand about your health and your options for care, the better.

What if a medical note is incorrect?

Minor errors in medical notes are not rare: maybe you had your tonsils removed 30 years ago, not 10 years ago. But there can be more important errors: stating that arthritis in your left knee is severe when it’s actually the right knee that’s severe could lead to having x-rays (or even surgery!) on the wrong side. And not properly recording a family history of cancer or heart disease could mean missing out on timely screening tests or preventive treatments.

In an era of ever-increasing time pressure, use of voice recognition software, electronic record templates, drop-down menus, and ability to copy and paste text, it’s easier than ever for health care providers to make (and perpetuate) errors in the medical record.

If you do see an important error that could affect your health, ask your provider to amend it.

What if the language in a medical note seems offensive?

Numerous studies have highlighted the problem of stigmatizing language in medical notes that can leave people feeling judged or offended. Negative attitudes can affect the quality of our health care and willingness to seek care, and can also widen health disparities. One study linked stigmatizing language to higher rates of medical errors. Of note, this study found higher rates of stigmatizing language and medical error among black patients.

Examples include:

  • Depersonalization: A note might describe a patient as “a drug abusing addict” rather than a person struggling with drug addiction.
  • Insulting or inappropriate descriptors: Notes might contain subjective descriptions that paint the patient in an unflattering light without providing context. For example, the note might say “the patient is unkempt and is drug-seeking” rather than “the patient is experiencing homelessness and has severe, chronic pain.” If a person’s recall of medical events from the past is hazy, they may be called “unreliable.”
  • Dismissiveness: A medical note may suggest a symptom is not real or is exaggerated, rather than taking the complaint seriously.
  • An untrusting tone: Language such as “she claims she never drinks” or “he denies alcohol use” may suggest mistrust by the physician.

Why might this happen, anyway?

How does such language make its way into medical notes? (To be clear, these possible explanations are not justifications.)

  • Tradition and training: Medical trainees, like other learners, tend to follow the lead of their mentors. So if stigmatizing language is used by an instructor, trainees may do the same.
  • Time pressure: With medical documentation (as in most everything else), mistakes are more common if you’re rushing.
  • Bias: Like everyone else, doctors have biases, including ones they aren’t aware of. How we are taught to think about people — by family, by society — can spill over into every area of life, including work.
  • Frustration: Doctors may feel frustrated by patients who don’t follow their recommendations. That frustration can be reflected in their medical notes. For example, a note may say, “As expected, the patient’s blood sugar is high; he is still not checking his blood sugar or following the diet recommended by his nutritionist.”

If the language in a note is confusing or bothersome, ask about it. The Open Notes movement and federal legislation have given most of us much better access to our medical records. This has worthy goals — greater transparency and better communication with people about their medical care — and unintended consequences.

Is changing language in notes that health practitioners once shared mainly with each other a positive consequence? Mostly. Yet some doctors worry that notes will become less specific, accurate, or useful since they may leave out information that might upset a patient.

The bottom line

I encourage you to read your health providers’ notes about your care. If there is a substantial error or something you find confusing or objectionable, ask about it. By the way, a signed medical note cannot usually be revised. However, your doctor can make clarifications or correct mistakes in an addendum at the end of the note.

As more and more patients read their medical notes, it’s likely that health providers will be more conscientious about the language they use. So, wide access to medical notes may improve not only people’s understanding of their health, but also the quality of notes over time.

It's worth remembering that the medical note is not the most important thing that happens during a visit to your doctor. A great note isn’t the same as great care, and vice versa. Still, your medical notes can be a valuable source of health information that differs from all others, including trusted health sites and social media: they’re written by your doctor and they’re all about you.

About the Author

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

Ultra-processed foods? Just say no

2 metal shopping carts, one filled with ultraprocessed foods and one filling with colorful, healthy fruits and vegetables

Americans love their ultra-processed foods, whether they come as cereal (like Cap’n Crunch, a favorite of mine as a kid), snack foods (like Cheetos), entr’es (like hot dogs), or desserts (like Twinkies). Sure, loading your plate with vegetables, fruits, fish, healthful oils, and grains in a Mediterranean-style diet boosts heart and brain health. But if you also eat some ultra-processed foods, is that bad for your brain health?

What to know about this new study

A new study appears to deliver resounding yes: eating ultra-processed foods is linked to a greater risk of cognitive impairment and strokes.

This well-designed observational study examined data from the REGARDS (REasons for Geographic And Racial Differences in Stroke) project, a longitudinal study of non-Hispanic Black and white Americans ages 45 years and older. Study participants were initially enrolled between 2003 and 2007 and were given a number of questionnaires evaluating health, diet, exercise, body mass index, education, income, alcohol use, mood, and other factors. In addition, tests of memory and language were administered at regular intervals.

To examine the risk of stroke and cognitive impairment, data from 20,243 and 14,175 participants, respectively, were found usable based on the quality of the information from the questionnaires and tests. Approximately one-third of the sample identified as Black and the majority of the remaining two-thirds identified as white.

The results of the study

  • According to the authors’ analysis, increasing the intake of ultra-processed foods by just 10% was associated with a significantly greater risk of cognitive impairment and stroke.
  • Intake of unprocessed or minimally processed foods was associated with a lower risk of cognitive impairment.
  • The effect of ultra-processed foods on stroke risk was greater for individuals who identified as Black compared to individuals who identified as white.

Study participants who reported following a healthy diet (like a Mediterranean, DASH, or MIND diet) and consumed minimal ultra-processed foods appeared to maintain better brain health compared to those who followed similar healthy diets but had more ultra-processed foods.

Why might ultra-processed foods be bad for your brain?

Here are some biologically plausible reasons:

  • UPFs are generally composed of processed carbohydrates that are very quickly broken down into simple sugars, equivalent to eating lots of candy. These sugar loads cause spikes of insulin, which can alter normal brain cell function.
  • Eating ultra-processed foods is associated with a higher risk of metabolic syndrome and obesity, well-established conditions linked to high blood pressure, abnormal blood lipid levels, and type 2 diabetes.
  • There are unhealthy additives in ultra-processed foods to change the texture, color, sweetness, or flavor. These additives disrupt the microbiome in the gut and can lead to gut inflammation that can cause
    • the production of microbiome-produced metabolites that can affect brain function (such as short-chain fatty acids and lipopolysaccharides)
    • leaky gut, allowing toxins and inflammatory molecules to enter the bloodstream and go to the brain
    • altered neurotransmitter function (such as serotonin) that can impact mood and cognition directly
    • increased cortisol levels that mimic being under chronic stress, which can directly impact hippocampal and frontal lobe function, affecting memory and executive function performance, respectively
    • an increased risk for Alzheimer’s, Parkinson’s, and other neurodegenerative diseases due to inflammatory molecules traveling from the gut to the brain.
  • Because ultra-processed foods have poor nutritional value, people will often be hungry shortly after eating them, leading to overeating and its consequences.

The take-home message

Avoid processed foods, which can include chips and other snack foods, industrial breads and pastries, packaged sweets and candy, sugar-sweetened and diet sodas, instant noodles and soups, ready-to-eat meals and frozen dinners, and processed meats such as hot dogs and bologna. Eat unprocessed or minimally processed foods, which — when combined with a healthy Mediterranean menu of foods — include fish, olive oil, avocados, whole fruits and vegetables, nuts and beans, and whole grains.

About the Author

photo of Andrew E. Budson, MD

Andrew E. Budson, MD, Contributor; Editorial Advisory Board Member, Harvard Health Publishing

Dr. Andrew E. Budson is chief of cognitive & behavioral neurology at the Veterans Affairs Boston Healthcare System, lecturer in neurology at Harvard Medical School, and chair of the Science of Learning Innovation Group at the … See Full Bio View all posts by Andrew E. Budson, MD

Swimming lessons save lives: What parents should know

Four children in the shallow end of the pool having a swimming lesson with their instructor; children are standing in the water holding up blue kick boards

Before going any further, here’s the main thing parents should know about swimming lessons: all children should have them.

Every year, over 4,500 people die from drowning in the United States — and, in fact, drowning is the leading cause of death for children ages 1 to 4. Swimming lessons can’t prevent all of those deaths, but they can prevent a lot of them. A child doesn’t need to be able to swim butterfly or do flip turns, but the ability to get back to the surface, float, tread water, and swim to where they can stand or grab onto something can save a life.

10 things parents should know about swimming lessons

As you think about swimming lessons, it’s important to know:

1. Children don’t really have the cognitive skills to learn to swim until they are around 4 years old. They need to be able to listen, follow directions, and retain what they’ve learned, and that’s usually around 4 years old, with some kids being ready a little earlier.

2. That said, swim lessons between 1 and 4 years old can be useful. Not only are some kids simply ready earlier, younger children can learn some skills that can be useful if they fall into the water, like getting back to the side of a pool.

3. The pool or beach where children learn must be safe. This sounds obvious, but safety isn’t something you can assume; you need to check it out for yourself. The area should be clean and well maintained. There should be lifeguards that aren’t involved in teaching (since teachers can’t be looking at everyone at all times). There should be something that marks off areas of deeper water, and something to prevent children from getting into those deeper areas. There should be lifesaving and first aid equipment handy, and posted safety rules.

4. The teachers should be trained. Again, this sounds obvious — but it’s not always the case. Parents should ask about how teachers are trained and evaluated, and whether it’s under the guidelines of an agency such as the Red Cross or the YMCA.

5. The ratio of kids to teachers should be appropriate. Preferably, it should be as low as possible, especially for young children and new swimmers. In those cases, the teacher should be able to have all children within arm’s reach and be able to watch the whole group. As children gain skills the group can get a bit bigger, but there should never be more than the teacher can safely supervise.

6. There should be a curriculum and a progression — and children should be placed based on their ability. In general, swim lessons progress from getting used to the water all the way to becoming proficient at different strokes. There should be a clear way that children are assessed, and a clear plan for moving them ahead in their skills.

7. Parents should be able to watch for at least some portion. You should be able to see for yourself what is going on in the class. It’s not always useful or helpful for parents to be right there the whole time, as it can be distracting for children, but you should be able to watch at least the beginning and end of a lesson. Many pools have an observation window or deck.

8. Flotation devices should be used thoughtfully. There is a lot of debate about the use of “bubbles” or other flotation devices to help children learn to swim. They can be very helpful with keeping children safe at the beginning, and helping them learn proper positioning and stroke mechanics instead of swimming frantically to stay afloat, but if they are used, the lessons should be designed to gradually decrease any reliance on them.

9. Being scared of the water isn’t a reason not to take, or to quit, swimming lessons. It’s common and normal to be afraid of the water, and some children are more afraid than others. While you don’t want to force a child to do something they are terrified of doing, giving up isn’t a good idea either. Start more gradually, with lots of positive reinforcement. The swim teacher should be willing to help.

10. Just because a child can swim doesn’t mean he can’t drown. Children can get tired, hurt, trapped, snagged, or disoriented. Even strong swimmers can get into trouble. While swimming lessons help save lives, children should always, always be supervised around water, and should wear life jackets for boating and other water sports.

The Centers for Disease Control and Prevention website has helpful information on preventing drowning. The American Red Cross offers an online water safety course for caregivers and parents and water safety videos for children. Many public pools and organizations like Boys & Girls Clubs and the YMCA offer swimming classes for all ages.

About the Author

photo of Claire McCarthy, MD

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

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

Life can be challenging: Build your own resilience plan

Colorful paper cutouts of a thunderstorm at sea with dark clouds, lightening, fish jumping, and a red and white boat bobbing in the waves; concept is resilience

Nantucket, a beautiful, 14-mile-long island off the coast of Massachusetts, has a 40-point resiliency plan to help withstand the buffeting seas surrounding it as climate change takes a toll. Perhaps we can all benefit from creating individual resilience plans to help handle the big and small issues that erode our sense of well-being. But what is resilience and how do you cultivate it?

What is resilience?

Resilience is a psychological response that helps you adapt to life’s difficulties and seek a path forward through challenges.

“It’s a flexible mindset that helps you adapt, think critically, and stay focused on your values and what matters most,” says Luana Marques, an associate professor of psychiatry at Harvard Medical School.

While everyone has the ability to be resilient, your capacity for resilience can take a beating over time from chronic stress, perhaps from financial instability or staying in a job you dislike. The longer you’re in that situation, the harder it becomes to cope with it.

Fortunately, it’s possible to cultivate resilience. To do so, it helps to exercise resiliency skills as often as possible, even for minor stressors. Marques recommends the following strategies.

Shift your thoughts

In stressful situations, try to balance out your thoughts by adopting a broader perspective. “This will help you stop using the emotional part of your brain and start using the thinking part of your brain. For example, if you’re asking for a raise and your brain says you won’t get it, think about the things you’ve done in your job that are worthy of a raise. You’ll slow down the emotional response and shift your mindset from anxious to action,” Marques says.

Approach what you want

“When you’re anxious, stressed, or burned out, you tend to avoid things that make you uncomfortable. That can make you feel stuck,” Marques says. “What you need to do is get out of your comfort zone and take a step toward the thing you want, in spite of fear.”

For example: If you’re afraid of giving a presentation, create a PowerPoint and practice it with colleagues. If you’re having conflict at home, don’t walk away from your partner — schedule time to talk about what’s making you upset.

Align actions with your values

“Stress happens when your actions are not aligned with your values — the things that matter most to you or bring you joy. For example, you might feel stressed if you care most about your family but can’t be there for dinner, or care most about your health but drink a lot,” Marques says.

She suggests that you identify your top three values and make sure your daily actions align with them. If being with family is one of the three, make your time with them a priority — perhaps find a way to join them for a daily meal. If you get joy from a clean house, make daily tidying a priority.

Tips for success

Practice the shift, approach, and align strategies throughout the week. “One trick I use is looking at my calendar on Sunday and checking if my actions for the week are aligned with my values. If they aren’t, I try to change things around,” Marques says.

It’s also important to live as healthy a lifestyle as possible, which will help keep your brain functioning at its best.

Healthy lifestyle habits include:

  • getting seven to nine hours of sleep per night
  • following a healthy diet, such as a Mediterranean-style diet
  • aiming for at least 150 minutes of moderate-intensity activities (such as brisk walking) each week — and adding on strength training at least twice a week
  • if you drink alcohol, limiting yourself to no more than one drink per day for women and two drinks per day for men
  • not smoking
  • staying socially connected, whether in person, by phone or video calls, social media, or even text messages.

Need resilience training?

Even the best athletes have coaches, and you might benefit from resilience training.

Consider taking an online course, such as this one developed by Luana Marques. Or maybe turn to a therapist online or in person for help. Look for someone who specializes in cognitive behavioral therapy, which guides you to redirect negative thoughts to positive or productive ones.

Just don’t put off building resilience. Practicing as you face day-to-day stresses will help you learn skills to help navigate when dark clouds roll in and seas get rough.

About the Author

photo of Heidi Godman

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

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