Month: March 2023

Ever see ads for products that promise to supercharge immunity? Activate your body’s natural defenses? Support a healthy immune system while delivering a potent boost derived from nature’s hottest immune-enhancing ingredients?

While the words may change to reflect the latest trends, the claims certainly sound amazing. But do the multitude of products promoted as immune boosters actually work? What steps can we take to support the immune system? Both are important questions, especially in the wake of a deadly pandemic and as flu and cold season arrives.

IV drips, supplements, cleanses, and superfoods

The lineup of immune-boosting products and advice includes:

• Home intravenous (IV) drips. Want a health professional to come to your home with IV fluids containing various vitamins and supplements? That’s available in many US cities, and some companies claim their formula is designed to supercharge immunity. These on-demand IV treatments aren’t risk-free and can be quite expensive.
• Vitamins and supplements. Popular options include turmeric, milk thistle, and echinacea, often in combination with various vitamins. Hundreds of formulations are available.
• Superfoods and foods to avoid. If you search online for “foods to boost the immune system” you’ll see thousands of articles touting blueberries, broccoli, spinach, dark chocolate, and other foods to keep infections away. There’s also a list of foods to avoid, such as sugary drinks or highly processed meats, because they’re supposed to be bad for your immune system.
• Cleanses and detox treatments. No doubt you’ve seen pitches for cleanses and detox products intended to remove toxins from the body. Their marketing warns that the environment is full of harmful substances that get into the body through the air, water, and food, which we need to remove. Advocates suggest that, among other harmful effects, these often unnamed toxins make your immune system sluggish.

Are the heavily marketed IV drips, supplements, or detox products endorsed by the FDA?

No. In fact, the standard disclaimer on supplements’ claims of immune-boosting properties says: “This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.”

Yet sellers are allowed to use phrases like “boosts immune function” and “supports immune health.” These terms have always seemed vague to me. More importantly, they’re confusing:

• Boosting immunity is what vaccinations do. They prime your immune system to help fight off a specific infectious organism (like the flu shot before each flu season).

• Immune support typically describes vitamins such as vitamin C, or other nutrients necessary for a healthy immune system. It’s true that a deficiency of vital nutrients can cause poor immune function. But that doesn’t mean a person with normal levels of nutrients can expect supplements to improve their immune system.

Can products marketed as immune boosters actually boost immunity?

Unless you have a deficiency in a key nutrient, such as vitamin C or zinc, the short answer is no.

That is, there’s no convincing evidence that any particular product meaningfully improves immune function in healthy people. For example, results of studies looking at various supplements for colds and other similar infections have been mixed at best. Even when taking a particular supplement was linked to reduced severity or duration of an infection like a cold, there’s no proof that the supplement boosted overall immune function.

This goes for individual foods as well. None has ever been shown to improve immune function on its own. It’s the overall quality of your diet, not individual foods, that matters most. A similar approach applies to advice on foods you should avoid, such as sugary drinks or highly processed meats: the best foods to avoid in support of your immune system are the same ones you should be limiting anyway.

How to get the most out of your immune system

It’s not a secret and it’s not a product. What’s good for your overall health is good for immune function. The best ways to keep your immune system at peak performance are:

• Eat well and follow a heart-healthy diet, such as the Mediterranean diet.
• Exercise regularly and maintain a healthy weight.
• Don’t smoke or vape.
• If you drink alcoholic beverages, drink only in moderation.
• Get plenty of sleep.
• Minimize stress.
• Get regular medical care, including routine vaccinations.
• Take measures to prevent infection such as frequent hand washing, avoiding people who might have a contagious illness, and wearing a mask when it’s recommended.

This list probably looks familiar. These measures have long been recommended for overall health, and can do a lot to help many of us.

Certain illnesses — HIV, some cancers, and autoimmune disorders — or their treatments can affect how well the immune system works. So some people may need additional help from medications and therapies, which could truly count as immune boosting.

The bottom line

Perhaps there will come a time when we’ll know how to boost immune function beyond following routine health measures. That’s simply not the case now. Until we know more, I wouldn’t rely on individual foods, detox programs, oral supplements, or on-demand IV drips to keep your immune system healthy, especially when there are far more reliable options.

About the Author

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

The most common cause of chronic stomach pain in children isn’t anything you can find on a test or cure with a medicine. And that can make it very challenging to diagnose — and treat.

You may not have ever heard of functional abdominal pain. Yet it ranks as the most common cause of stomach pain lasting two months or more in children and teens.

What is functional abdominal pain?

The mind and the body are tightly connected in ways that we are still working to understand, and this is particularly true of the mind and the gastrointestinal tract. Stress — particularly chronic stress, depression, and anxiety — can lead to pain that is very real. Sometimes the pain is the only symptom of stress, especially in children who are high-achieving or tend to hide their emotions.

Sometimes the pain doesn’t start from stress but from an infection or other illness, and stays once the illness is gone or adds additional pain to the illness while it is being treated. Worry about the pain and its possible cause can make things worse. The nervous system of the gut can go into overdrive.

What are common symptoms of functional abdominal pain?

Children with functional abdominal pain can have mild symptoms that just show up occasionally, or they can have more severe symptoms that interfere with daily life. Along with stomachaches, they can have nausea, vomiting, constipation, or diarrhea — or some combination of all of them. They may have a poor appetite or complain of feeling full very quickly.

When should you contact your child’s doctor?

It’s important to check in with your doctor if your child is having chronic stomachaches. They should have a physical examination, and your doctor may want to do some testing, such as blood or stool tests, as there are many medical conditions that can cause chronic stomachaches.

It’s particularly important to call your doctor if your child

• is losing weight
• has blood in their stool
• has severe pain
• has fever, rashes, sore joints, or other signs of illness.

If your doctor finds that your child’s examination and tests are normal, and they aren’t losing weight, chances are that your child has functional abdominal pain.

For some families, getting this diagnosis sounds like the doctors are saying that it is all in the child’s head. But nothing could be further from the truth. It is very real pain — but it is not being caused by something dangerous, which is very good news.

How can you help a child diagnosed with functional abdominal pain?

There are many ways to help a child who has functional abdominal pain once the diagnosis is made. They include:

• Understanding and managing stressors in the child’s life, if there are any
• Medications recommended by your health care team can help with symptoms, such as laxatives for constipation
• Cognitive behavioral therapy, which is a kind of therapy that teaches strategies for managing pain, as well as managing any stress or sadness that can be contributing
• Meditation, yoga, and other ways for a child to relax and regulate how they react to their world
• For some children, a low-FODMAP diet can be helpful
• Probiotics, peppermint oil preparations, and some other supplements are sometimes used to help soothe and prevent pain.

Most children with functional abdominal pain can receive care from their pediatrician. Regular visits are a good idea, to check in to see how things are going and adjust any treatments. If things aren’t getting better, a referral to a gastroenterologist can be helpful.

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

When was the last time you had your blood pressure checked? All adults should have this simple test at least once a year.

If a blood pressure reading at your doctor’s office is elevated — that is, higher than a healthy range — current guidelines from the US Preventive Services Task Force recommend repeating the measurement outside of a clinic setting before starting treatment. But that’s not the only reason why your doctor may suggest regularly tracking your blood pressure at home.

Why monitor blood pressure at home?

“Some people have blood pressure elevations only at the doctor’s office, which is known as white-coat hypertension,” says Dr. Stephen Juraschek, associate professor of medicine at Harvard-affiliated Beth Israel Deaconess Medical Center. One of the best ways to know if your blood pressure is truly higher than normal is to measure it multiple times at home.

Home monitoring is also a good idea:

• if your doctor asks you to track readings to help decide if you need to start taking medication to lower blood pressure
• if you’ve been diagnosed with high blood pressure and need to adjust your medications to make sure you’re reaching your blood pressure target
• if you’re pregnant or had a baby in recent months and your health team is concerned about preeclampsia. This condition is a severe form of high blood pressure that can harm vital organs like the kidneys. When not promptly treated, it sometimes leads to seizures, stroke, or even death.

Which home blood pressure monitor should I buy?

• Look for a monitor that’s been validated, which means the device has been independently reviewed for accuracy.
• Avoid monitors that feature cuffs used on the wrist or fingertip. These aren’t as accurate as upper-arm cuffs.
• Choose and use the right size cuff. Measure the circumference of your upper arm midway between your elbow and shoulder. Most home monitor cuffs can accommodate arm circumferences of 9 to 17 inches, but smaller and larger cuffs are available. A too-small cuff can lead to an artificially high reading, while a loose cuff can give a falsely low reading. For example, a 2023 randomized study of automated blood pressure monitors tested a regular size cuff on adults who need a different size cuff. The researchers found systolic blood pressure readings increased 19.5 mm Hg for participants who should have used an extra-large cuff, and by 4.8 mm Hg for participants who should have used a large cuff.

Very basic models cost as little as $25. But more expensive models, which range from about $50 to $100, may be more convenient to use. They can store multiple readings and send the data to your computer or smartphone — or even directly to the patient portal at your doctor’s office.

Three key points about blood pressure readings

Home blood pressure monitoring is a bit more involved than some people assume. “It’s not something you just do sporadically or whenever you have time,” says Dr. Juraschek.

• Blood pressure fluctuates throughout the day, which means one isolated reading doesn’t provide accurate information.
• If you check your blood pressure when you’re upset or stressed, it’s likely to be high. If you take it again right away, you may get another high reading, which feeds a cycle of anxiety and elevated readings, he says.
• Consistent, repeated measurements provide a far more useful assessment than occasional measurements.

How often should you take your blood pressure at home?

Ask your doctor how often and what time of day to take your blood pressure.

“The gold standard for home monitoring is to take 28 separate measurements, which you can then average to get a representative reading,” says Dr. Juraschek.

That means taking your blood pressure four times a day — twice in the morning and twice in the evening — for seven days in a row. However, even 12 measurements over three days is reasonable, especially if you include one weekend day, Dr. Juraschek says. Your doctor can advise you about what makes the most sense for your situation.

How can you get an accurate blood pressure reading?

Common mistakes can raise your blood pressure reading by a few points, or as much as 10 or even up to 25 points in some cases. Here’s what to do or avoid — and why — for an accurate blood pressure reading.

Wait at least 30 minutes after smoking, consuming caffeine or alcohol, or exercising before taking blood pressure.

Why? Caffeine and nicotine constrict blood vessels and boost your heart rate, which can raise blood pressure. Alcohol dilates blood vessels, possibly lowering blood pressure. And exercise increases heart rate and blood pressure.

Empty your bladder.

Why? A full bladder can put pressure on and reduce blood flow to your kidneys. Your body’s natural response is to raise your blood pressure to make sure your kidneys are getting enough blood.

Sit comfortably, supporting your arm near heart height.

Sit back in your chair with your feet flat on the floor, legs and ankles uncrossed, and your arm extended, palm up, on a table so that your elbow is positioned roughly at heart height.

Why? Crossing your legs, especially at the knee, temporarily raises blood pressure. If your feet or your arm are not supported, your muscles will contract. Even this small amount of isometric exercise can raise your blood pressure. Also, supporting your arm below or above the level of your heart may affect the accuracy of the reading.

Wait a few quiet minutes before taking a reading.

First, wrap the proper size cuff around your bare arm about an inch above the crook of your elbow. Sit quietly for a few minutes without distractions like TV, reading, phone scrolling, or talking. Then start the machine to take your blood pressure.

Why? Putting the cuff over clothes — or pushing up your sleeve so that it’s tight around your upper arm — may interfere with an accurate reading, though evidence on this is mixed. Ideally, you want to record blood pressure while feeling relaxed, not distracted, because even minor stress or tension can raise your blood pressure.

This video from the American Heart Association demonstrates the correct technique.

Why is diagnosing high blood pressure so important?

Nearly half of all adults have high blood pressure, but about a third of these people aren’t even aware they have the problem. An accurate diagnosis and treatment is vital, says Dr. Juraschek. Few things in medicine have shown such consistent results as the harms of high blood pressure, which is a major cause of heart attacks, strokes, kidney disease, and cognitive decline.

“It’s called the silent killer for a reason. We don’t feel or experience any of high blood pressure’s effects until it’s too late,” he 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

About the Reviewer

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