Potassium Foods: A Practical Guide
Potassium is the third most abundant mineral in the human body.
Normal body function depends on tight regulation of potassium concentrations both inside and outside of cells. Potassium helps you regulate your fluid balance, send nerve signals and regulate muscle contractions. Low potassium concentration in the blood (hypokalemia) can result in muscular paralysis or abnormal heart rhythms and can be fatal.
Chronic hypertension damages the heart, blood vessels, and kidneys, thereby increasing the risk of cardiovascular disease. Increasing dietary potassium intake can help lower blood pressure as well as reducing your risk of stroke, kidney stones and osteoporosis.
Potassium is possibly the most neglected nutrient in our food system and is deemed to be a ‘nutrient of public health concern’, with less than 2% of Americans meeting their recommended daily potassium intake.
Because most of us are not getting enough, we have a powerful satiety response when we consume foods that contain more potassium.
Sodium vs potassium
Without the right balance of electrolytes (particularly potassium and sodium), your body can’t effectively utilise the energy from the food you eat.
When potassium dissolves in water, it produces positively charged ions (electrolytes) which maintain conductivity in your body.
The sodium-potassium pump is integral to your energy production and the movement of that energy around your body. The balance of potassium in the cell with the sodium outside your cells is critical to maintaining the flow of energy around your body.
Potassium depletion also induces sodium retention, which is associated with hypertension, diabetes and heart disease.
While we have intense cravings for salt, sodium could be a stop-gap measure when what our body wants is more potassium. You tend to need less sodium when you get enough potassium.
Potassium helps you do it with feeling
Nerve impulses are generated by sodium ions moving into cells and potassium ions moving out of cells. Your nervous system relays messages between your brain and body that help to regulate your muscle contractions, heartbeat, reflexes and many other functions.
Factors influencing potassium requirements
You may need more potassium if you:
- experience adrenal stress,
- are very active,
- have diabetes,
- are at risk of diabetic ketoacidosis,
- consume a lot of salt,
- drink a lot of coffee, tea, alcohol or sugar, or
- have kidney disease.
Satiety response to increased potassium
Our satiety analysis suggests that we consume a LOT less food when we prioritise foods that contain more potassium.
People who consume more potassium in their diet tend to consume around 30% fewer calories. This satiety response is stronger for potassium than any other micronutrient. Only protein has a stronger satiety response than potassium!
The average potassium intake of Optimisers is 3.4 g per 2000 calories with an 85th percentile intake of 5.3 g per 2000 calories.
The Recommended Daily Intake (RDI) for potassium is 4.7 g per day for an adult male while the Adequate Intake is 2.3 g/day. Potassium is the only nutrient that the average for Optimisers is less than the RDI.
Potassium stretch targets
Based on the powerful satiety response data, we have set a stretch target of 6.0 g of potassium for men and 4.8 g for women. Once you have started to get the hang of nutrient density, you could ‘level up’ by aiming for these stretch targets to truly optimise your nutrition.
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Can you get too much potassium?
While there is a limit to how much sodium you should consume, it seems almost impossible to overdo potassium from food. Many of the issues associated with excess sodium consumption can be mitigated by increasing the amount of potassium in your diet.
The chart below from the PURE study indicates that higher levels of potassium are beneficial. While there is an inflection point at around 2 g per day, there is no apparent downside to higher potassium intake at the levels achievable from food.
Availability of potassium in the food system
There has been a significant decrease in potassium in our food system since the widespread use of chemical fertilisers in the 1940s.
While the use of fuel-based fertilisers has enabled us to double food production and significantly increase the human population, faster-growing food tends to correspond with lower nutrient content. This decrease in potassium also aligns with the rise in obesity rates.
Typically available foods contain less than 2 g of potassium per 2000 calories compared to the DRI of 4.7 g per day for men and the stretch target of 6 g per day. So, to achieve your minimum recommended intake (let alone optimal levels), you will need to go out of your way to chase more potassium in your diet.
Insulin resistance and the keto flu
Your body upregulates insulin to hold onto electrolytes such as potassium when you’re not getting them from your diet. So, ironically, a low carb or keto diet (which can have a lack of dietary potassium) can inadvertently increase insulin resistance.
What is the optimal sodium : potassium ratio?
In days gone by, salt was rare and highly valued, so we evolved mechanisms for protecting against the threat of low sodium levels (i.e. we crave sodium and actively seek it out). However, because potassium was plentiful, we have not developed similar mechanisms to protect us against low potassium levels. In today’s food system, it is hard to get a lot of potassium without also consuming a significant amount of sodium.
Our Paleolithic hunter-gatherer ancestors are thought to have consumed about 11,000 milligrams (mg) of potassium a day from fruits, vegetables, leaves, flowers, roots, and other plant sources, and less than 700 mg of sodium. In days gone by our potassium:sodium ratio could have been as high as 10:1.
Nutrient Optimiser helps you manage your diet to ensure that you are not prioritising foods that contain more sodium if you are already getting plenty. If you are getting enough potassium, you probably won’t need as much sodium.
In practical terms, there is likely no harm using ‘salt to taste’ on your food, but you probably should be going out of your way to seek out more potassium, particularly given you don’t have the same cravings for potassium.
The Nutrient Optimiser algorithm sets a minimum of 1:1 potassium:sodium ratio. We find most people need to chase more potassium in their diet before they worry about supplementing large amounts of sodium.
While supplementing potassium can be useful, we recommend that you prioritise nutrients from your diet. If you do choose to supplement, you should start slowly.
Potassium supplements in tablet or capsule form are limited to 99 mg because they can affect heart function if you are on medications.
Don’t think that your mineral salt contains enough potassium either. Using Lite Salt on your meals (i.e. a mixture of sodium and potassium) and supplementing with potassium citrate powder seems to be the only meaningful way to top up your potassium.
If you want to make sure you are getting enough potassium, we recommend you track your diet in Cronometer and top up with potassium citrate powder and/or Lite Salt to ensure you are meeting your targets. As always, start slowly, and titrate up with more potassium until you reach optimum levels.
Potassium works synergistically with vitamins B6, D, bicarbonate, calcium, insulin, magnesium, phosphate and sodium.
Potassium-rich food sources
Foods highest in potassium tend to be green veggies such as the ones listed below (i.e. not bananas!):
- green peppers
- sweet potato
The nutrient fingerprint chart below shows that we can obtain adequate potassium from a nutrient-dense diet. A diet with more potassium tends to be high in fibre (non-starchy veggies) and less fat.
Nutritious foods to naturally boost your potassium
If you are experiencing any of the symptoms of low potassium or are concerned that your current vitamin D intake is low, then you may be interested in our lists of potassium-rich foods and meals.
What you will get:
- Our Nutritional Optimisation Kickstart Guide,
- A list of the most popular 50 foods that contain more potassium,
- A list of 100 popular foods that contain potassium, and
- An even longer list of 150 common foods that contain more potassium to allow you to expand your nutrient-dense repertoire further.