Potassium deficiency (and how to get enough potassium)

From the desk of
Robb Wolf
SciencePotassium deficiency (and how to get enough potassium)

Between 60 and 80% of American adults are potassium deficient: They aren’t consuming enough potassium to meet the target recommended by the National Academy of Medicine (NAM): 3,400 mg/day for men and 2,600 mg/day for women.

This is due, in large part, to folks eating the majority of their total calories from processed foods, which are lacking in potassium. The target wasn’t picked at random. It’s based on evidence that sufficient potassium intake reduces the risks of high blood pressure and kidney stones. Yet only a fraction of people — including health-conscious people — are potassium sufficient.

Why? Simple. It can be difficult to get enough potassium through diet alone. Even eating plenty of fruits, vegetables, and other potassium-rich foods, you may still fall short. Add to this my processed foods point above, and potassium deficiency becomes a widespread issue.

I spend a lot of time talking about sodium, but potassium is the yin to sodium’s yang. And while it’s not demonized like sodium, potassium still doesn’t get enough love in most folks’ diet and supplement routines. I wrote this article to help change that.

The Need for Potassium

Want a sense of how important potassium is to your body? A colossal 20–40% of your body’s ATP (cellular energy) serves to power a protein called the sodium-potassium pump. The pump is a complex piece of biology, but the simple story is that ATP helps pump two potassium ions into the cell and three sodium ions out of the cell.

Put another way, up to 40% of your body’s cellular energy is dedicated to shuttling potassium ions around town. That’s one really important passenger!

In a tangible sense, potassium structures many systems that keep your body humming. Here are a few things potassium does for you:

  • Keeps blood pressure within healthy ranges by relaxing blood vessel walls and balancing the effects of sodium
  • Functions as an electrolyte to transmit messages throughout your nervous system
  • Decreases kidney stone risk by increasing calcium absorption
  • Improves glycemic control by supporting insulin secretion
  • Counteracts acidic conditions that can lead to osteoporosis
  • Supports healthy hydration and fluid balance in bodily tissues

The need for potassium is most apparent in the data on hypertension (high blood pressure). In study after study, higher potassium intakes are linked to lower blood pressures.

Potassium supplementation is also extremely promising for hypertension. In one 2017 meta-analysis, researchers concluded that taking potassium supplements could effectively improve high blood pressure.

Potassium Deficiency vs. Low Blood Potassium

Potassium deficiency is akin to low dietary intakes of potassium. It’s different from the medical condition of low blood potassium called hypokalemia.

In people with healthy kidneys, it’s rare for low dietary potassium to cause hypokalemia. The more likely suspects include diarrhea, vomiting, the use of laxatives or diuretics, inflammatory bowel disease (IBD), and refeeding syndrome following a period of severe calorie restriction.

Even at low potassium intakes, your body does a good job keeping blood potassium levels within normal ranges. When you need extra, it pulls it from your body’s reserve stores (like from your bones). This explains, in part, why potassium deficiency is linked to decreased bone mineral density.

While potassium deficiency may increase the risk of hypokalemia, most people who are potassium deficient won’t manifest low blood levels of potassium. Therefore, a normal result on your electrolyte panel says very little about your overall potassium status.

How do you triangulate a potassium deficiency, then? Simply assess your dietary potassium intake, and check for the symptoms of potassium deficiency. I’ll cover how to assess your potassium intake later. Let’s review the symptoms up-front.

Symptoms of Potassium Deficiency

Unless you routinely monitor your biomarkers, the signs of potassium deficiency can be difficult to detect. They include:

  • Elevated blood pressure
  • Lower bone mineral density
  • Increased calcium excretion (i.e., increased risk of kidney stones and osteoporosis)
  • Insulin resistance

The easiest marker to monitor is blood pressure. Just buy a cuff and occasionally take your blood pressure from the comfort of your couch at the same time each day. Ideally, you want to hit 120/80 or lower. If your systolic blood pressure (the top number) is over 130, or your diastolic blood pressure (the bottom number) is over 80, you meet the American Heart Association’s criteria for high blood pressure. In these situations, bumping up your potassium intake is typically a good thing.

Chronically low potassium intakes can also cause transient spurts of mild hypokalemia, leading to muscle cramps, fatigue, constipation, muscle weakness, and malaise. Keep in mind, however, that many of these symptoms can also suggest a sodium or magnesium deficiency.

Keep in mind that there are many different factors that could contribute to any one of the symptoms listed above. You should take these symptoms as clues pointing toward potassium deficiency, not concrete evidence.

What Causes Potassium Deficiency?

Here are the major factors driving poor potassium status.

#1: Low dietary intakes

If most of your food comes wrapped in plastic, I’d be willing to bet that you’re potassium deficient. The best sources of potassium are fruits, vegetables, meat, and fish. I’m talking about avocados, bananas, spinach, swiss chard, sweet potatoes, potatoes, tomatoes, salmon, chicken, beef, and many others.

Needless to say, the modern diet is often low in these healthy foods. Yet even more health-conscious folks may struggle to get enough potassium. Take a low-carb or keto diet, for instance. When you limit carbs, you also limit potassium-rich foods like fruits and root vegetables. Sure, you can make up for it with dark leafy greens and meat (and I recommend you try). But it’s difficult to consume an optimal amount of potassium on keto without supplements.

#2: Illness and medications

Common issues that may drain your potassium supply include vomit, diarrhea, and urine. Any illness that causes these issues (cholera, for instance) will accelerate potassium losses. In severe cases, they can skyrocket you straight past potassium deficiency and into hypokalemia.

Similarly, any medication with a laxative or diuretic effect may also deplete potassium. Diuretic medications (often prescribed to treat heart or kidney failure) may explain why 21% of hospitalized patients develop low potassium levels. This is why clinicians often include potassium along with sodium and fluids in the IV drip.

How To Get Enough Potassium

To determine your potassium status, start with a full dietary assessment. Simply download any diet tracking app, log your meals for about 3 days, and see how much potassium you’re getting each day.

I shoot for 3.5–5 grams of potassium per day based on the latest evidence. While this may overshoot the mark for some people, most people have no real downside to getting a little extra potassium. Low potassium intakes, on the other hand, have tangible health consequences like high blood pressure.

In addition to prioritizing potassium-rich foods, you can also supplement potassium directly to hit your target. If you decide to supplement, try to dose throughout the day alongside your meals — nutrients work better together than in isolation. LMNT, our tasty electrolyte drink mix, includes 200 mg of potassium chloride in every stick pack.

As you adjust your potassium intake, monitor potassium-related signs and symptoms, and how you feel overall. I hope this article has been helpful!

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