#339 14 Reasons Why You Got AFib

14 Reasons Why You Got AFib

So, why did you get atrial fibrillation? There are a lot of possible substrate causes—some of which you can control and some of which you cannot. Below is a list of the 14 most common reasons why our patients have developed AFib.

1. You Inherited the Wrong Gene

Some people inherit a genetic predisposition that makes AFib more likely. Up to a third of all people who have atrial fibrillation without another identified cause have a familial history of the condition.

At least fifteen different “potassium channel” mutations have been linked to AFib and at least seven “sodium channel” mutations are associated with AFib. Potassium and sodium ions are atoms that carry electric charges and thus are essential to the signaling system that tells parts of the heart to contract in rhythm. But a lot of non–ion-channel mutations have been linked to AFib, too. These include mutations in a protein-coding gene called NUP155; a gene linked to many heart disorders known as LMNA; a gene called NPPA that encodes a vital hormone created in the heart; and a set of genes known as GATA4, GATA5, and GATA6 that are key to the development of new heart tissue.

Those aren’t the only genes that have been linked to AFib, though—there are actually more than one hundred. Even if we were to create an exhaustive list, it would soon be outdated. Emerging research is revealing other “candidate genes” that may have links to AFib. For now, however, there isn’t a test that can scan all of the known and potential “AFib genes.”

While over-the-counter commercial DNA tests can scan for some, you’re really just scratching the surface with these products. What’s important to note is that while it can be very helpful to know whether you’ve inherited a genetic predisposition to AFib, there’s nothing we can do about the genes we were dealt.

However, it is equally important to understand that research conducted over the past few decades in the field of epigenetics has conclusively demonstrated that we do have the power to influence which genes are “expressed” and which genes are “silenced” based on the hundreds of little health decisions we make every day. Indeed, health outcomes among the individuals who have inherited any of these genes vary greatly based on factors that extend far beyond that inheritance.

2. You Have Another Heart Problem

If you were to round up all of the people with AFib in the world, you would find that somewhere close to half of them have also been diagnosed with another cardiovascular condition. Of these, the three most common culprits are heart failure, cardiac valve problems, and coronary artery disease.

3. You’ve Got a Few Years Under Your Belt

Margaret had been a picture of health for most of her life. She had followed a mostly plant-based diet free of fried, processed, and fast foods. She didn’t eat sugar. She’d never been overweight. She did aerobics every day at the gym and attended a yoga class three times a week. She practiced deep-breathing exercises whenever stress levels were getting too high. She slept well at night. She even volunteered as a crosswalk guard at the elementary school across the street from her house. And since no one in her family had ever been diagnosed with AFib, she was more than a little irritated when her doctor told her she had that arrhythmia.

But here’s the thing: Margaret was ninety-four years old. And the truth is that even if your genes are perfect and you do just about everything right, you can still get AFib as a result of age. Just as your skin will wrinkle over the years, the simple act of living life will put some wear and tear on your heart cells over time.

But there’s a big difference between being ninety-four and fifty-four—between AFib that results from natural aging and AFib that comes about due to premature aging. Most of the AFib cases we see are due to the latter kind of aging. And while there is nothing we can do to stop how many candles are on our birthday cakes—that’s chronological age—there is plenty we can do to slow the process of biological aging.

4. Your Blood Pressure Is Too High

Hypertension occurs when the force of a person’s blood against the walls of their arteries is high enough that it puts a person at risk of health problems. Within the heart, this means that, with every heartbeat, the organ is working harder to pump blood through more restrictive arteries. And all of this strain on the heart can cause its muscle to thicken and enlarge, disrupting electrical pathways and causing AFib. Indeed, of all of the factors that have been associated with atrial fibrillation, none may be stronger than hypertension. High blood pressure is the most commonly encountered condition in AFib patients, and research has shown that it nearly doubles the risk of developing atrial fibrillation.

Studies show that 90 percent of Americans are hypertensive by age fifty-five, so it’s little wonder why AFib is so common. It doesn’t have to be this way. Only 4 percent of the centenarians living in southern China’s famed “Longevity Village” of Bapan, the people we studied in our best-selling book The Longevity Plan, had high blood pressure. That finding is similar to studies of hunter-gatherers living in the Amazon rainforest or elsewhere in the world consistently showing a natural blood pressure of about 110/70 that doesn’t increase much, if any, with age.

Indeed, it appears from many studies that our genes are designed to keep our blood pressure naturally in this 110/70 range without medication as long as we don’t mess things up with our modern lifestyle. Low body weight, a mostly plant-based diet devoid of sugar and processed foods, daily physical exercise, rejuvenating sleep, and low perceived stress levels protected these people from the scourge of hypertension. It might seem like it’s impossible in a modern context to live as these people do, and that’s true. But the lessons we can draw from these elders are virtually endless, and your ability to apply these lessons to your own life are limited only by your imagination.

5. It’s One of these 11 Medications You Are On

Here is a link to an article I wrote: The 11 Worst Medications For Causing Atrial Fibrillation

6. Too Much Exercise

Over the years, we explained, we have noticed a particularly increased risk of atrial fibrillation in patients who regularly compete in ultra-endurance events, including running, biking, and cross-country skiing. Most of our patients are shocked when they learn that people who run marathons, competitively cycle, or do Ironman Triathlons are five times more likely to develop atrial fibrillation.

Also, it bears noting that while aggressively competing in endurance sports might put you at a greater risk of AFib, participation in these activities certainly does not guarantee you’ll get AFib. It is reassuring to note that recreational participation in endurance sports, even if it is a marathon or triathlon, doesn’t seem to increase this risk.

7. You’re Not Getting Enough Exercise

And regular exercise in general isn’t risky at all—in fact, it’s exceptionally protective. To put things into perspective, for every thousand patients we see with atrial fibrillation, perhaps one may be at risk for atrial fibrillation due to overexercising. The biggest problem, by far, is that most patients aren’t exercising enough. There is far greater risk from not exercising enough than from exercising too much. People who live sedentary lifestyles are at significant risk of AFib, not to mention all of the other health consequences of not getting enough exercise.

8. You’re Overweight

Nearly three-quarters of American men and nearly two-thirds of American women are overweight, if not obese. Today more than two billion people worldwide are overweight or obese In fact, the scientific data connecting weight and AFib are so compelling that many electrophysiologists (EPs) specializing in heart rhythm disorders feel that carrying extra weight is a primary cause of AFib.

Our research has shown that even a few extra pounds can make a big difference in a person’s AFib risk and how they respond to treatments. Other studies have shown that carrying too much weight is the main cause of an enlarged left atrium and premature heart aging—two critical components in the development of AFib.

Even if it’s only by a few extra pounds, being overweight can significantly raise your risk of AFib as we showed in one of our studies. And maybe it’s not just a few pounds. Perhaps you are obese. That word has a lot of negative baggage attached to it, which may be one of the reasons why people are reluctant to even step on the scale. Consciously or subconsciously, they simply don’t want to know. But when people do check, many are surprised to learn that they might indeed be obese, which substantially increases the risk of atrial fibrillation.

9. You Have Diabetes or Pre-Diabetes

Just about everyone knows that obesity puts people at risk of lots of other health challenges, especially diabetes. And it stands to reason that diabetes and obesity have been shown to be associated with an elevated risk of AFib, too.

Not only is your risk of AFib substantially increased with diabetes or pre-diabetes but your experience with that disease is likely to be a lot worse, as people with diabetes have worse AFib symptoms, report a lower quality of life, are more likely to spend time in a hospital, and experience higher mortality rates. There is good news in this regard, though: type 2 diabetes (also known as adult-onset diabetes, although children are increasingly affected) is usually reversible through weight control and processed carbohydrate reduction/elimination. That makes it manageable.

Manageable doesn’t mean “easy.” We live in a world that is constantly conspiring against us when it comes to the food choices that drive so many of our metabolic challenges. It’s also a world in which we’re constantly being told there are shortcuts to just about everything. But we’ll go to battle against those forces very soon. And we’ll do it together. It is something that even we, as cardiologists, have to battle every day. But, again, the important thing, at this moment, is to understand if this is one of the challenges you are facing. If so, the first step is to acknowledge that challenge, and accept its connection to AFib.

10. You’re Not Eating the Right Foods

Food is good medicine. A diet that respects what our bodies need to thrive might be the best way to prevent atrial fibrillation, or to beat it back once it starts.

A bad diet does the exact opposite. In fact, there isn’t much that is worse for you, when it comes to AFib, than eating foods loaded with sugar and other simple/processed carbohydrates. The Standard American Diet (the acronym “SAD” is tragically telling) has way more sugar than anyone needs, and it’s a veritable mass-delivery system for other simple carbs, which your body breaks down to create fast energy.

Most people know that if they’re trying to eat healthy, they should avoid sugar-filled foods like pastries, confections, and candies, along with sugary sodas. What many people fail to recognize is that many of the foods we often think of as “healthy” are also packed with sugar. Even “healthy natural sugars,” like honey, still cause our bodies to respond in roughly the same way: a sudden shockwave of sugar courses through our blood, and these bloodsugar fluctuations may cause cardiac scarring, which, over time, can cause atrial fibrillation.

Another bulk supplier of simple carbs in many people’s diets are refined grains like white flour and white rice, which have been stripped of most of their natural nutrients and fibers. The more processed a grain is, the faster it will be digested to sugar. That has the added consequence of making these foods less filling, so when you eat a white rice dish or a piece of white toast, you’re bound to be hungry again very soon. Sadly, even whole wheat bread isn’t much better. A single slice can spike your blood glucose higher than a Snickers bar.

That doesn’t mean you should avoid carbs altogether. Not at all. In fact, some researchers believe that while working to limit carbs in general might be a good idea, exceptionally low-carb diets may actually lead to a greater risk of AFib.

The key is making sure that, to the greatest extent possible, the carbohydrates you’re getting are complex carbs, including fruits and especially vegetables. For now, though, it’s important to do a realistic assessment of your habits related to sugars and processed carbs. Anyone who isn’t actively avoiding foods with any and all types of added sugar, and limiting their processed or simple carbohydrate intake to those foods that are packed with complex carbohydrates (think vegetables and fruit), may be at an increased risk of AFib.

11. Your Thyroid Hormone Levels Are Off

Thyroxine is the main hormone created by the thyroid gland, and people suffering from hyperthyroidism have bodies that make way too much of it. That’s a big problem because thyroxine is a potent cardiac stimulant. In a way, having hyperthyroidism is like having a little energy-drink factory in your neck. So, you can see why people who have hyperthyroidism might experience increased heart rates, palpitations, and arrhythmias such as atrial fibrillation.

The scary thing is it doesn’t take full-blown hyperthyroidism to increase the risk of AFib. For example, our research showed that when people had thyroid hormone levels in the higher end of normal, they were 40 percent more likely to develop AFib.

12. Your Sleep is Off 

13. You’re Too Stressed

Psychological stress has long been thought to be a possible trigger of atrial fibrillation, and the association appears to be strong among women. But men aren’t immune. Neither are cardiologists. Indeed, we have treated countless doctors over the years with AFib as well as innumerable CEOs, lawyers, accountants, politicians, athletes, celebrities, and others who have come to see us for treatment largely because of the enormous stresses they are under.

What kinds of challenges can create stress that triggers AFib? A research group in Denmark concluded that the severely stressful experience of losing a partner increased the risk of atrial fibrillation for an entire year.

Another international group of researchers found that divorced men had a higher incidence of death associated with atrial fibrillation. And a group from Sweden revealed a potential dose-response relationship between work-related stress, like getting fired from a job, and atrial fibrillation. In fact, the Swedish researchers found that just the experience of having a job with high psychological demands and with little control over your work situation could increase your AFib risk by 50 percent.

When Yale University researcher and electrophysiologist Dr. Rachel Lampert surveyed the way her patients were feeling emotionally to see if she could predict whether or not they would go into AFib that day, the results were absolutely startling. In a 2014 study published in the Journal of the American College of Cardiology, she noted that feelings of sadness, anger, stress, impatience, and anxiety increase the risk of an AFib attack up to 500 percent in the same day. Happiness, meanwhile, appears to be protective. If you are feeling happy, you are 85 percent less likely to have your heart go out of rhythm that day, according to Lampert’s research.

Thus, it is no surprise that those who deal with deep and abiding feelings of sadness and disengagement might be even more at risk. Depression is simply not good for the heart, especially when it comes to AFib. One study showed that depression increases the risk of AFib by up to 700 percent. Fortunately, this same study showed that getting your depression treated dramatically reduces your risk. But with more than 16 million Americans, and hundreds of millions of others around the world, dealing with depression, there are a lot of people who have a significant risk factor for AFib and don’t even know it.

But emotional and mental stress aren’t the only things that can send your body into a state of chaos. Researchers have connected AFib episodes to physical stressors caused by events like surgery, bad infections, and car crashes.54 In the case of irregular, singular events like those, there is a chance that after the stressor has passed, the AFib will go away. More likely, though, this is a harbinger of things to come. Our hearts are remarkably resilient, but if an incident of great stress pushed you into AFib, something else has likely been pushing you toward that precipice a long time before that incident occurred.

14. You’re a Smoker or Live in a Polluted City

If you haven’t been to Salt Lake City, it’s worth a trip. Nestled into the foothills of the splendid Wasatch Mountains, there are few cities in the world that boast such immediate access to the outdoors. In the summer, it’s a paradise for hikers and mountain bikers. For skiers and snowboarders, the winters are simply legendary.

Sounds nice, right? Well, before calling the moving company, there’s another thing you should know about Utah’s capital city. Because it rests in a valley, nearly surrounded by mountains, it suffers from lengthy inversions: weather events in which cold, polluted air gets trapped under a blanket of warmer air. During these periods, studies show, the air can get more harmful with each passing hour and can even increase the incidence of deadly diseases.

Among these diseases is atrial fibrillation; researchers have demonstrated a significant association between the development of AFib and the gaseous pollutants most often found in toxic air. Can bad air trigger individual AFib events? That question was at the heart of one of our early studies to assess the risks of short-term elevations in exposure to fine-particulate air pollution. Fortunately, our study failed to identify any measurable risk, so an occasional trip to a place where the air is bad isn’t likely to trigger an AFib episode, particularly if it’s brief.

In the long term, however, bad air can be a very bad thing. While not everyone has a choice about where they live, everyone can choose what they voluntarily put in their bodies. Yet across the globe, more than one billion people smoke or vape tobacco products, according to the World Health Organization. You won’t be surprised to learn that people who smoke have a substantially increased risk of developing atrial fibrillation,  not to mention all of the other health problems smoking causes, from cancer to emphysema. Even living or being around a smoker can increase your AFib risk. Every pack of cigarettes an adult smokes on an average day increases their children’s risk of getting AFib by 18 percent. That’s a legacy no parent wants to leave. Regardless of how toxic air gets into your lungs, if it’s there, there’s a good chance it has increased your risk of AFib.

Are you motivated to beat your AFib? If so, give my office in Salt Lake City, Utah a call to set up a consultation. Sorry, initial consultations all have to be in-person.

If you liked the photo with this article it was a picture I took this past week mountain biking with my teenage son overlooking Jupiter Bowl at the Park City Mountain Resort.


Disclaimer Policy: This website is intended to give general information and does not provide medical advice. This website does not create a doctor-patient relationship between you and Dr. John Day. If you have a medical problem, immediately contact your healthcare provider. Information on this website is not intended to diagnose or treat any condition. Dr. John Day is not responsible for any losses, damages or claims that may result from your medical decisions.

  1. Hi Doctor, unless I missed it I think you missed a big cause in my struggle with A-fib. Alcohol. I’ve finally quit alcohol (after 3 ablations & lots of money) , and I firmly believe I might not have ever gotten a-fib were it not for alcohol .

  2. I have aFib since May 2022. After taking Digoxin for two months I had a very bad reaction. I was so dizzy and it took two days to get out of my system. I had a cardio version on August 4 and on the 6 I was back with aFib. Beta blockers are not good for me because my blood pressure is under 110 in the morning after my walk. One mile in 24 minutes. The electro cardiologist recommended an ablation. Because I don’t take any medication other than Xarelto (blood thinner) my cardiologist advised me to wait. I am an 80 years old female I am very active and if my Apple Watch didn’t tell me that I have aFib I wouldn’t know. My cardiologist said. Get rid of the watch 🤣🤣🤣

  3. Dear dr. John
    I am subscriber of your newsletter and have found it’s very informative.
    Having AFIB for many years, I have been prescribed some of the 11 medication
    that you’re mentioned .
    I do noticed, that taking beta-blockers or anti arrhythmic drugs as prescribed
    ( 3 or 2 times daily) the AFIB could be triggered.
    Therefore, I was taking as PRN .
    But lately AFIB episodes became often, severe and scary!!
    And usually normal blood pressure and HR ( heart rate ) are starting to jump
    from high up to down and to long QT .
    Than I take double portion of metoprolol and Flecainide, trying to avoid ER visits
    and Dioxin injection ,that also have triggered AFIB.
    What a “ catch 222.” !

  4. If we take some of the above collectively, you describe Metabolic Syndrome. So if you have that, I wonder how much greater the risk for the combination is than any of those individually?