Updated: Jan 24
Sodium and potassium are two minerals which are found in the soil. Plants absorb and assimilate them, and when we eat the plants they ready for use in the body. It might seem strange to think that these minerals which are found in vegetables, fruits and grains are actually metals, known as electrolytes to produce electrical signals and control water balance.
Sodium and Potassium are a ubiquitous pairing. They work together acting as a chemical battery, driving nerve and muscle signals which are then converted into energy. This process happens in our cell walls; we are made of trillions of cells and each cell has pump structures which bring potassium into the cell and push sodium out. This strict equilibrium between the two minerals maintains the chemical balance within our cellular environment, (blood pH) and regulates blood pressure.
A Brief History
Around 2 million years ago our ancestors most likely ate a diet consisting of fruits, vegetables, flowers, roots, berries, leafy greens and barks; foods rich in potassium and low in sodium. In nature sodium is usually found in lesser amounts than potassium; as such our body has evolved to hold on to sodium and freely excrete potassium. Yet, our modern day Western diets provide the opposite - instead we obtain high levels of sodium and much less potassium than our ancestors.
As societies evolved from the Hunter-Gatherer era and into the Agricultural age, the use of salt in our diets increased; salt was used as a preservative but at this point still balanced with a diet of potassium rich plant foods. Continue on until the 1950's and that is when we see a real increase in dietary sodium, with the boom in processed, sodium-laden foods.
Salt is artificially added to commercial foods most often containing excessive levels of sodium compared to unprocessed food items, for example:
100g of chicken breast: 77mg of sodium and 247mg of potassium
100g Carrots: 6mg sodium and 320mg potassium
100g Broccoli: 33mg sodium and 316mg potassium
One egg:124mg sodium and 126mg potassium
Olives (stored in brine) 1556mg sodium and only 42mg of potassium
1 teaspoon of salt which contains a whopping 2300mg of sodium
A packet of noodles: around 1700mg of sodium
A chicken nugget holds 95mg of sodium (with only) 22mg of potassium.
What about Potassium?
Why would we have low potassium levels? There are a few reasons to consider. Firstly we eat fewer plant-based foods than our ancestors but secondly, the vegetables and plant foods are much less nutritious in our current times. Studies have analysed foods from our current day to the 1930's onwards, demonstrating losses of around 40-60%, which is quite a decline!
Why? Since the 1950's intensive farming methods have become commonplace, reducing the microbiome of the soils and creating nutrient depleted soils. Our old farming practices used to leave fields fallow so the microorganisms could repopulate, crops were rotated and animals placed on the land to give back to the soil and replenish lost nutrients from the previous crops. Intensive farming totally misses out this ancient wisdom; the microorganisms have a vital role to play making nutrients available for absorption by the crops and nutrient deficient soils produce nutrient deficient crops.
Most often crops are grown in artificial environments or the soils are treated with imbalanced fertilisers; whilst this produces fast growth it also provides foods with imbalanced nutrition, away from what nature intended. And, if you consider that nutrients deplete over time, well, most of our food is at least a couple of weeks old before it even hits the shelves in the supermarket, having been flown from one side of the world to another. Pre-1950’s we ate locally, seasonally and foods were generally consumed within a few hours or days of being gathered; typically prepared with minimal processing to retain their vital goodness. So really, it should be easy to see how we should be eating far more than the minimum of 5-a-day.
What if our dietary patterns favoured one electrolyte more than another?
The daily current requirement for sodium is set at 1500 -2300mg. Americans, on average, consume 3,300mg of sodium per day - which is over the recommended level. Whilst at the same time only obtaining 2600mg per day of potassium instead of the required 4700mg.
Increased sodium levels are often associated with high blood pressure and water retention but research has demonstrated that sodium isn't necessarily the bad guy. Whilst reducing dietary sodium does reduce blood pressure in some 'salt sensitive' individuals, that is not always the case. For example, Japanese cultures have high intakes of dietary sodium as well as potassium, due to the consumption of hydrating vegetable based dishes. Whilst blood pressures are on average higher, Japan has a heathy ageing population with less cases of cardiovascular disease compared to our Western counterparts. This evidence suggests that the ratio between these two minerals should be the area of focus.
The standard American diet has an average potassium to sodium ratio of 0.6:1 and a high incidence of cardiovascular dis-ease. Current research suggests we should be aiming for a 2:1 ratio at least (twice the amount of potassium to sodium) to benefit our health.
You see, potassium and sodium go hand in hand. Excess sodium can be freely excreted out the body but at the expense of potassium. If potassium levels are low the body must find a way to keep hold of the incoming potassium and that means holding onto sodium too. Holding onto sodium also means holding onto additional water ('where salt goes, water goes') which increases blood volume and therefore blood pressure.
Mild symptoms such as cramps, headache, waking up unrefreshed, lack of sleep, irritability, anxiety, numbness may be signs of low potassium and high sodium. More serious electrolyte imabalances affect muscle movement, with the biggest muscle being the heart! Heart-disease, high blood pressure and low energy can be signs of excess sodium; constricting our blood vessels which can pressurise the heart and cardiovascular system. Secondly, our cellular pH (level of acidity) must remain in homeostasis (balance) to live vitally. Cellular replication requires enzymatic reactions which are literally orchestrated by minor pH fluctuations so you could imagine any significant changes to cellular pH could change the way our cells replicate.
Our body is very clever and has a back-up plan to protect our fragile DNA, ensuring blood pH stays within range but at detriment optimal health. The minerals, calcium and magnesium, are brought into the cell which act as buffers to reduce cellular acidity. Whilst this is a great protective mechanism it comes at a cost as calcium can be leeched from our bones or excessive removal of calcium can accumulate in the kidneys and bladder as stones, for example.
Electrolyte imbalances are a classic root cause of dis-ease, yet, nutrition is rarely considered in the fight against chronic dis-ease. I always like to mention the common fish tank analogy which is very true!
Do we put medicine into the fish tank or change the water? There is always a place for the medicine but shouldn't we fix the environment first?
As for our doggies friends, they don't suffer from cardiovascular dis-ease in the same way as humans do (they are carnivores) and they can freely excrete sodium the electrolytes should be balanced - be mindful, always include a source of calcium from bone or eggshell, include so magnesium and potassium vegetables and avoid giving excessive sodium-laden commercial foods as treats.
There are clear dietary changes since the 1960s which are impacting on our health. Obtaining more sodium that potassium is a common pattern. Why not check out our other blog, Potassium Broth, to find out a simple way to obtain more potassium in your diet. Or come and join our HOAP course and learn all about nutrition and eating whole-foods as nature intended, from a well-being and complementary perspective, the choice is yours.
This information is not intended to replace medical advice. Should you suffer from a medical condition you should inform your doctor before making any changes; especially if you suffer from a kidney or heart condition. This article is written for information purposes and interest only.
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Pirahanchi Y, Aeddula NR. Physiology, Sodium Potassium Pump (Na+ K+ Pump) [Updated 2019 Jan 21]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2019 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK537088/
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