Most “veteran” afibbers know all about the importance of magnesium for atrial fibrillation. As you’ll soon discovery, potassium is just as important. Most people with atrial fibrillation have magnesium and potassium deficiencies.
Like magnesium, potassium can play a key role in helping to prevent episodes of atrial fibrillation. Potassium prolongs the amount of time the heart rests between beats. This is called the refractory period. By contrast, low potassium levels leave the heart in an unusually excitable state with much shorter refractory periods, making it easier to slip into afib.
The relationship between potassium and atrial fibrillation cannot be overstated. Anyone with atrial fibrillation needs to pay as much attention to potassium as they do to magnesium. Potassium has a profound impact on heart health and optimized potassium levels may even help prevent afib attacks.
This is an exhaustive blog post on potassium. It’s over 3,800 words! My goal when putting this together was to have everything you need to know about potassium for atrial fibrillation in one resource. If you just want the bottom line, skip to the end of this post and read the summary.
What is Potassium?
Potassium is one of the major electrolytes found in the human body. Other important electrolytes include sodium, calcium, bicarbonate, magnesium, chloride, and phosphate. Electrolytes regulate the heartbeat and help muscles function correctly. Any deficiency in any electrolyte can affect your heart rhythm and overall health.
Electrolytes get depleted through sweat and other normal bodily elimination processes. This is why athletes replenish their electrolytes after a hard workout. This is also why people who do a lot of vomiting or suffer from diarrhea when they are sick need to worry about electrolyte replacement.
As long as your electrolyte levels are in balance, all is well. Your blood pressure remains stable, your heartbeat remains regular and your muscles function as they should.
Potassium and Overall Heart Health
Potassium is not only important for people with atrial fibrillation but it’s important for anyone seeking optimal heart health. Consider this from NurtionFacts.org:
A review on all the best studies ever done on potassium intake and its relationship to two of our top killers: stroke and heart disease, was recently published in the Journal of the American College of Cardiology. A 1600 mg. per day higher potassium intake was associated with a 21% lower risk of stroke. That still wouldn’t get the average American up to the minimum adequate intake, but it may be able to wipe out a fifth of their stroke risk.” –NutritionFacts.org
Got high blood pressure? Your potassium levels might just be too low. Potassium can help dilate your blood vessels which improves blood flow and reduces pressure. Potassium also stimulates sodium secretion. With less sodium, you won’t retain as much water which will lower blood volume, thus lowering blood pressure.
How Much Potassium Should You Get?
More than 98% of Americans are potassium deficient. The standard American diet is usually far too light on fruits and vegetables, and most natural potassium comes from plant-based foods. By contrast, the diet of our ancestors consisted almost exclusively of fruits and vegetables so they got ample amounts of potassium; some say as much as 10,000mg per day!
The recommended dose for adults and teens is 4,700/mg of potassium per day but healthy adults with normal kidney function can probably consume much more.
In his book, “The High Blood Pressure Solution: A Scientifically Proven Program for Preventing Strokes and Heart Disease,” Richard D. Moore, MD, PhD, wrote:
…if a person has normal kidney function, up to 6,800 mg/day of potassium has been reported as not being dangerous for an adult. Dr. David Young, Dept. Physiology and Biophysics (U of Mississippi School of Medicine) has been a pioneer in studying the regulation of potassium within the body. Dr. Young reports that healthy adults consumed as much as 10,000 mg/day of potassium without ill effects.
Please don’t misinterpret that quote. I’m not recommending you aim to get massive doses of potassium! In fact, too much potassium can be fatal. I’m simply pointing out that the recommended daily dose of 4,700mg is probably a minimum for optimal health.
You should strive to get at least 4,700mg of potassium per day but if you get a little more that’s probably going to be o.k. for most healthy people with normal kidney function. Unfortunately, most of us don’t even come close to getting 4,700mg of potassium. Track your potassium intake from foods for a few days. You’ll be shocked at how little potassium you get!
What Happens When You Don’t Get Enough Potassium?
When potassium levels drop below 3.0 mEq/L (mEq/L stand for milliequivalents per liter of blood) the body enters a condition known as hypokalemia. Hypokalemia can lead directly to cardiac arrhythmia and atrial fibrillation.
But hypokalemia can also cause:
- Muscle weakness
- Decreased appetite
What Happens When You Get Too Much Potassium?
When potassium levels rise to 5.0 mEq/L the body enters a state known as hyperkalemia, which can be as bad as hypokalemia.
Hyperkalemia can cause arrhythmia and atrial fibrillation too, as well as a host of other life-threatening complications. It can lead to heart attack. Other symptoms often go unrecognized, but can include:
- Confusion or brain fog
- Muscle cramps
- Muscle weakness
The idea is to keep potassium within an optimal, healthy range (3.5-5.0 mEq/L).
What Drugs Affect Potassium Levels?
Anyone with atrial fibrillation who wants to begin tackling a potassium deficiency needs to be aware of the way certain drugs may be impacting potassium levels in the body. Some drugs lower potassium levels and others increase potassium levels.
Drugs that lower potassium levels include:
- Diuretics (Lasix, Bumex, HCTZ, Chlorthalidone)
- Abuterol (Proair, Proventil)
- Sudafed (Over-The-Counter)
- Laxatives & Enemas
- Some antipsychotic medications (Risperdal, Seroquel)
Drugs that raise potassium levels include:
- ARB drugs (Losartan, Telmisartan, Valsartan, Ibesartan)
- ACE inhibitors (Lisinopril, Enalapril, Quinapril)
- Any combination pill including ACE inhibitors, ARBs and HCTZs together
- Aldactone drugs (Spironolactone)
- Over-the-counter NSAIDs such as Motrin, Advil, and Aleve
- The blood thinner Heparin
- Azole antifungals
- Amilorides (Midalnor, Dyrenium )
- Beta Blockers (Propranolol, Labetalol, Atenolol)
If you’re taking these drugs you must watch your potassium levels closely, especially if you are considering potassium supplements of any kind or are already taking them! Combining any of these drugs with supplements could potentially be fatal. Dietary changes may ultimately offer a better solution for anyone taking any of these drugs.
Managing Potassium Levels Through Diet
It probably won’t come as much of a surprise to learn that the bulk of the foods of the Standard American Diet lowers potassium levels. These acidic foods that deplete potassium levels include:
- Other processed, sugary foods
Some of these foods offer benefits in their own right, particularly meat protein, but most of us tend to eat these foods excessively while avoiding fruits and vegetables that help replenish potassium levels.
To complicate things, some of the fruits and vegetables that have high levels of potassium, such as bananas and potatoes, are high glycemic foods. What is an afibber to do? I encourage people with afib to strive to at least moderate their diet or follow one of the recommended diets for atrial fibrillation.
Another challenge when trying to manage potassium levels through diet is that the standard meal servings of fruits and vegetables may be insufficient to keep potassium levels up. You will have to eat a lot of whole fruit and vegetables in a day to maintain proper potassium levels (and probably more than you can feasibly consume in a day).
One way to get a high concentration of potassium from fruits and vegetables without gorging yourself is to drink fruit and vegetable smoothies, low-sodium V8, and organic vegetable juice. These are all options that can help you pack large doses of potassium-rich foods into your diet without forcing you to pile more food on your plate than you can handle.
For your reference, here are the top 10 potassium-rich foods:
- Avocado (1 whole) – 1,076mg
- Acorn squash (1 cup) – 896mg
- Spinach (1 cup cooked) – 839mg
- Sweet potato (1 large) – 855mg
- Wild-caught salmon (1/2 fillet) – 772mg
- Dried apricots (1/2 cup) – 756mg
- Pomegranate (1 whole) – 667mg
- Coconut water (1 cup) – 600mg
- White beans (1/2 cup) – 502mg
- Bananas (1 large) – 487mg
Low-sodium V8 isn’t on that list but it could be as it packs a whopping 1,018mg of potassium in just 8 ounces! However, tread lightly with it because it contains potassium in the form of potassium chloride which can cause gastrointestinal discomfort (see below). Incorporating low-sodium V8 or any of the foods listed above in your diet can go a long way towards increasing your potassium levels.
Potassium Levels and Exercise
You can lose up to three grams of potassium per day with extensive exercise due to perspiration, which means if you are performing serious athletic activity you’ll need to make sure you replenish with at least three grams of potassium just to make up for the loss. Don’t forget to factor in any medications you may be taking which may lower or raise potassium levels as well.
If you don’t replace the potassium you lose from exercise you may find yourself feeling exhausted and experiencing muscle fatigue. You may also find yourself in afib!
The Potassium, Salt, and Magnesium Connection
Potassium works hand-in-hand with other electrolytes, particularly salt and magnesium. You need to find the proper balance among these electrolytes to help maintain normal sinus rhythm. Let’s talk about sodium first.
Potassium and Sodium
Salt depletes potassium and unfortunately most people eat way too much salt. The average American gets 3,400 mg of sodium every day. Sodium is a vital nutrient, but you shouldn’t be getting more than 2,300 mg/day for optimum health. Source: MayoClinic.org
According to some, you don’t really need more than 100-300 mg a day for good health. Even if you don’t spend a lot of time salting your food you’re still getting more than you need. You can thank processed foods for that.
Processed, canned foods are some of the worst culprits. Some canned vegetables contain up to 1700 mg of sodium. A single meal at a restaurant can pack as much as 2,300mg of salt, or almost the entire daily recommended level of sodium!
Most Americans have a potassium-to-sodium (K:Na) ratio of less than 1:2. This 1:2 ratio indicates people ingest twice as much sodium as potassium. Researchers recommend a ratio of 5:1 to maintain health…or 10 times higher than the average intake.
Dr. Betty Kamen, PhD, theorized that the way our body handles potassium and sodium may go back to our original hunter-gather days. She wrote the following in her book, “Everything You Always Wanted to Know About Potassium but Were Too Tired to Ask“:
With such important duties, nature must have provided a way for you to secure and utilize the right amount of these elements and it has. Potassium, the surprising chairman of the board, is found in abundance in uncooked fruits and vegetables—especially in the rinds, husks, and stalks of edible plants. Potassium intake has always been very substantial.
Sodium, on the other hand, is relatively scarce in natural foods. The original hunter-gatherers ingested a diet high in potassium, but low in sodium. Perhaps that’s the reason your kidneys easily remove excess potassium from your blood. Your metabolism is more frugal with sodium, simply because under natural conditions, there is less of it to be found and eaten. So your body handles sodium with a more sparing kind of metabolism. Your kidneys actually hoard sodium.
Average kidneys slow the loss of sodium to a mere 10 mg. A day if the mineral is in short supply. Daily minimum potassium loss can be as high as 240 mg a day or 24 times the amount of sodium that is easily extracted.
The bottom line is most of us get way too much sodium which seriously impacts our efforts to maintain proper potassium levels. Reducing your sodium intake will go a long way in helping to increase potassium levels. In fact, it might be fair to call it step one of the process, even before you start trying to address ways to increase your potassium levels through diet or supplements.
Potassium and Magnesium
Magnesium deficiencies cause massive problems at the cellular level which impacts potassium levels. In short, magnesium deficiencies often lead to low potassium levels. From the book, “The Magnesium Factor, written by Mildred Seeling, MD:
If the level of magnesium within a cell becomes too low there are three dire results:
- There is not enough ATP available for the cell’s necessary energy actions and to maintain the “enzymatic pump” that moves potassium into and sodium out of the cells.
- Potassium leaves the cell and cannot re-enter, and there is a temporary increase in the plasma-potassium level, which creates a risk of arrhythmia.
- Calcium rushes into the cell, where it does not belong, and creates its excitatory and hardening havoc.
Seeling is referring to the sodium-potassium pump. This brief video does a great job of explaining the sodium-potassium pump in layman’s terms:
Magnesium activates this sodium-potassium pump, which tells the cell to release sodium and bring in potassium. An indepth forum thread at afibbers.org discusses the sodium-potassium pump and magnesium’s role by saying:
Magnesium is important in regulating the intracellular potassium content. Intracellular magnesium activates membrane-bound magnesium-dependent sodium-potassium ATPase, which pumps sodium out of the cell in exchange for potassium. In addition, extracellular magnesium retards cell efflux of potassium on a biophysical basis. Thus, magnesium deficiency impairs the sodium-potassium pump and allows potassium to escape from the cell, to be lost in the urine.
Bottom line, magnesium depletion can lead to low potassium levels. In fact, 46% of patients who have a potassium deficiency also have a magnesium deficiency. Massive supplementation of potassium may fail to correct potassium deficiencies until the magnesium deficit is repaired.
Before you even attempt to increase your potassium levels through diet or supplements, it’s imperative that you address magnesium levels first! Don’t worry about potassium until your magnesium levels are in a healthy range.
Dietary potassium is almost always preferable to supplementation. However, some people really need supplements. Athletes, the elderly, and people struggling with high blood pressure may not be able to eat enough potassium-rich foods to maintain proper potassium levels.
Before reaching for supplements, however, you need to check two things:
1. Are your kidneys healthy enough to handle potassium supplements?
2. Are your magnesium levels high enough to make your increased potassium levels worth the effort?
Kidneys are the main organs that control the balance of potassium by removing excess potassium into the urine. If your kidneys aren’t functioning properly and you’re taking high amounts of potassium supplements it can lead to hyperkalemia (see above). Don’t assume your kidneys are healthy just because you haven’t experienced any problems. Get tested first to confirm you have healthy, normal kidney function.
When it comes to potassium supplements there are tablets or powders. By law, potassium chloride tablets can only contain 99mg of potassium and aren’t recommended. In his book, “The Salt Solution,” Dr. Richard Moore wrote this:
We don’t recommend potassium chloride supplements. The reason the dosage is restricted by law to 99 mg is that concentrated potassium chloride can be corrosive and damage the stomach lining.
And Dr. Betty Kaman, PhD, wrote this about potassium chloride in her book, “Everything You Always Wanted to Know About Potassium but Were Too Tired to Ask“:
Potassium chloride was found in salt substitutes and in some supplements. As mentioned earlier, the chloride that remains when potassium is used may contribute to the retention of additional sodium, thereby defeating the purpose of the potassium supplementation. High levels, which would be necessary for supplementation, can cause gastrointestinal discomfort. Potassium chloride also interferes with Vitamin B12 absorption. The depletion of one nutrient affects the requirement for another, so it may be a round-robin of no-good effects.
Dr. Kaman recommends staying clear of potassium chloride. She also recommends that whatever potassium supplement you take doesn’t contain more potassium than you’d find in two bananas (~900mg) to avoid potassium overload.
Potassium powders, specifically potassium gluconate, glycinate, or citrate are gentler on the stomach than potassium chloride tablets and are more realistic to take. Let’s say you’re trying to get 1,600mg of potassium a day from supplements. If you take potassium tablets at 99mg each, you’d have to consume 16 tablets per day! In contrast, 1/4 teaspoon of potassium citrate powder has 448mg of potassium. You’d only need to take a little over ¾ of a teaspoon of potassium citrate powder per day to get 1,600 mg.
A Potassium Supplement Protocol
Based on my research, the recommended daily potassium dose from supplements is between 1,600-2,400mg/day. In other words, aim to get at least half of the recommended daily dose of 4,700mg from your diet.
As mentioned earlier, you must have good magnesium stores before supplementing with potassium. Assuming that’s the case, start your potassium supplementation slowly by taking around 500mg of potassium powder per day. Experiment and only add additional doses if you have ectopy (palpitations) or any kind of arrhythmia including atrial fibrillation that hasn’t responded to the initial 500mg dose. If you add additional doses do it in increments so you’d go from 500mg to 1,000mg. Observe your response to the additional dose. Did it help or make things worse? Adjust accordingly.
Don’t exceed 1,500 – 1,600mg in a day (at least initially) and make sure you’re taking sufficient magnesium along with your potassium! Consider taking vitamin B6 as well as it helps maintain the balance of sodium and potassium.
Finally, experiment with the types of potassium you take if you’re not getting good results. For example, you might find that potassium gluconate works better for you than potassium citrate or vice versa.
Recommended Potassium Supplements
Below are a few potassium supplements I recommend. Please note, the citrate powder has a lot more potassium per serving so watch your doses!
NOW Potassium Gluconate Powder (1/2 TSP = 175mg)
NOW Potassium Citrate Powder (1/4 TSP = 448mg)
NOW Potassium Gluconate Tablets (99mg/tablet)
NOW Potassium Citrate Tablets (99mg/tablet)
Pure Encapsulations Potassium Citrate Tablets (200mg/tablet)
Note: This supplement has double the amount of potassium per tablet than other tablets.
Testing Your Potassium Levels
For precision and safety, you should be actively measuring your potassium levels. Don’t assume your potassium levels are good (or bad). Get real data on how your actions are impacting the levels of potassium in your body. This is especially important if you’re thinking about reaching for a supplement.
Normal potassium levels are between 3.5 to 5.0 mEq/L. Most people with atrial fibrillation will want to see levels between 4.2 and 4.9 mEq/L. This range will typically keep the heart in NSR. This is a general range but realize everyone is different so your ideal range might be a little lower (4 – 4.1) or towards the high end of the range (4.9).
There are three ways to test your potassium levels.
1. Potassium Blood Test
The most common and convenient way to test is to have a potassium blood test from your family doctor. This is a very simple test that measures the amount of potassium in your blood serum. It’s not as accurate as the EXA test (see below) but it’s usually good enough to give you an indication of your potassium levels.
2. EXA Test
A more accurate test is the EXA test. The problem with this test is twofold. One, it’s hard to find a doctor that will administer it as it’s primarily offered by naturopathic doctors. Two, it’s expensive. It costs $200+ and insurance usually doesn’t cover it. This test requires a simple saliva sample and measures intercellular potassium so it’s very accurate.
3. Potassium Ion Meter
Finally, there’s home-based testing with a potassium-ion meter like this one by Horiba. Potassium-ion meters are convenient because they allow you to get readings throughout the day from the comfort of your home but they aren’t cheap. You’ll spend at least $300 for one.
Remember, potassium levels are always fluctuating – especially for people with atrial fibrillation as we tend to waste potassium and magnesium more than the average person does. Your levels at 10 am may be very different than what they are at 6 pm. The only way to get an accurate picture of your overall potassium levels is to test throughout the day. Only a potassium-ion meter will allow you to do that.
Potassium-ion meters require a simple saliva sample. I recommend you take readings periodically throughout the day when you are in NSR (normal sinus rhythm), and take readings when you are experiencing palpitations or atrial fibrillation. By doing this you’ll be able to determine what your potassium levels are when you are in NSR and what your levels are when you have palpitations or afib.
Recommended Potassium Books
- The High Blood Pressure Solution: A Scientifically Proven Program for Preventing Strokes and Heart Disease
- Encyclopedia of Nutritional Supplements: The Essential Guide for Improving Your Health Naturally
- Everything You Always Wanted to Know About Potassium but Were Too Tired to Ask
- The Salt Solution
Summary on Potassium and Atrial Fibrillation
If you’ve read this far you deserve a gold star! But in case you haven’t and you just want to cut to the chase, here is a summary of what you need to know about potassium and atrial fibrillation.
- Too much or too little potassium can cause palpitations and trigger episodes of atrial fibrillation. An ideal range to maintain NSR is usually between 4.2 – 4.9 mEq/L.
- Maintaining and monitoring potassium levels is as important to afibbers as maintaining and monitoring magnesium.
- You need a normal level of magnesium BEFORE supplementing with potassium. It’s an uphill battle to budge potassium levels if your magnesium levels are low.
- Salt depletes potassium. An easy way to increase potassium levels is to decrease sodium intake.
- Certain drugs can affect potassium levels. Some will increase your levels and others will decrease your levels. Know how your medications will impact your potassium levels!
- Sweating from heat and exercise will deplete potassium levels. Be sure to replenish potassium levels if you sweat a lot.
- Try to get around 5,000mg of potassium a day with at least half of it from foods. The more potassium you can get from foods the better!
- Before taking potassium supplements be sure you have normal healthy kidney function! Don’t assume you have healthy kidneys. Get tested first!
- Limit potassium supplements to no more than 2,500mg per day and but ideally between 1,600 – 2,000mg per day.
- Make sure you are taking adequate amounts of magnesium along with your potassium supplements.
- If you are taking potassium supplements, stick with powders (gluconate or citrate).
- Test your potassium levels periodically so you know what levels keep you in NSR and what levels give you palpitations and afib episodes.
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