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Guide to Electrolytes

Rachel Lett, RNutr

Head of Coaching


The importance of electrolytes should never be underestimated. These are essential minerals; magnesium, potassium, sodium, chloride, calcium, bicarbonate and phosphorus.

Quite literally, they supercharge the body, with electrical signals. Electrolytes are charged ions, which control the movement of water though the body, and maintain muscle and nerve function. Without these important elements, we’d be pretty lifeless, to say the least!

Symptoms Associated with Electrolyte Deficiency

I’m going to deep dive into three common electrolyte deficiencies, sodium, magnesium and potassium. The list of deficiency symptoms associated with these minerals just goes to show what a profound effect they have on our health and everyday functioning:

— Muscle weakness
— Muscle cramping and twitching
— Nausea
— Irritability
— Trouble sleeping
— Abnormal bowel movements
— Brain fog
— Headaches
— Fatigue
— Irregular or fast heart beat

If you’ve given a nod to any of these symptoms, or you’re about to embark on nutritional ketosis, don’t sweat it. This article will discuss techniques to guide you toward electrolyte balance. If you haven’t got the time to read this article today, use our simple electrolyte cheat sheet.

This will help you pinpoint possible deficiencies, and how to address them through food and supplements. Keep it handy for quick reference!

Electrolytes and Nutritional Ketosis

As we discussed in “What is Nutritional Ketosis”, electrolyte balance is particularly important during the initial phases of nutritional ketosis. This is because lower carb intake, reduces insulin and increases glucagon, which in turn stimulates a diuretic effect — up-regulating the kidneys to excrete water and electrolytes.

This is a normal and expected response to a lower carb diet, however a careful eye on electrolyte balance is essential to mitigate side effects of electrolyte deficiency.

Is Food Adequate or Do You Need To Supplement?

A well formulated ketogenic diet is a nutritionally complete way of eating and arguably more nourishing, and fulfilling than a western diet. You will likely consume more bioavailable minerals with this way of eating, however, with all diets, there are some situations where a helping hand from supplements is necessary.

On top of this, the need for supplementation has become ever more necessary due to over farming and depletion of minerals in the soil, where our food grows.


The requirement for sodium is critically underrated. Guidelines suggest a maximum intake of 2.4 grams of sodium, which translates to about oneteaspoon (6g) of salt. These guidelines have been driven by the idea that too much sodium causes high blood pressure.

A study of more the 2,600 people, over a 16 year follow-up period showed that those who had a higher intake (on average 3.7g) of sodium had the lowest blood pressure.

“While we expected dietary sodium intake to be positively associated with both SBP [systolic blood pressure] and DBP [diastolic blood pressure], the opposite was found.” — Lynn L. Moore et. al

To add to this, another study has shown that a low sodium diet is more at risk of mortality and cardiovascular events, than a high sodium diet— the optimal range for health being between 3–6g sodium per day. This is well above the current guidelines and translates to about 1.25–2.5 teaspoons of salt. This can be a difficult requirement to meet, especially when following a low-carb diet, where whole foods are mostly eaten.

Maybe try a little experiment, just to see what your intake is—measure out 1.25–2.5 teaspoons for a day, and see how much you get through. I bet you’d be quite surprised by the minor dent you make in your salt pile — I know I was!

Turning salt restriction on its head, I urge you to salt food (with sea or Himalayan salt, preferably) and drink bone broth daily, to make sure you’re getting enough sodium each day. Here is our recipe for making homemade bone-broth, but understandably, when that’s not feasible, there are some good shop bought alternatives from Ossa, and Coombe farm .


Due to inadequate intake, poor absorption and soil depletion, most people have insufficient magnesium levels. The recommended daily intake in the UK is 300mg for men and 270mg for women.

These values vary considerably with each country as the requirement is poorly understood—blood tests for magnesium are inaccurate and do not show total body magnesium (in tissue). In addition, low magnesium levels don’t always present with obvious symptoms, so deficiency is often overlooked.

Conditions associated with deficiency is ever growing, so special attention to magnesium intake is vital for everybody, and even more so for those following a low-carb diet and/or insulin resistance — magnesium deficiency in type 2 diabetes is well recorded.

The first call to action is to increase consumption of magnesium rich foods, and then add a supplement for good measure.

Here is a list of magnesium sources you may consider adding to your diet :

— Hemp seeds
— Swiss chard
— Pumpkin seeds
— Mackerel
— Chia seeds
— Cacao
— Dark chocolate
— Almonds
— Spinach
— Pine nuts
— Avocado
— Artichoke

It’s very rare to consume too much magnesium, given how efficient our bodies are at excreting it, so even if you are consuming a magnesium rich diet, a supplement wouldn’t go astray. There are a few options here :

Magnesium citrate is a popular supplement, which is highly absorbable. It calms the central nervous system, so ideal to take before bed, for a sound night sleep. Magnesium citrate draws water into the intestine, so can be used to alleviate constipation. On the other hand, this effect can cause diarrhoea in those with normal bowel movements. In this instance, magnesium glycinate is an appropriate alternative, which is gentler on the tummy, but still highly absorbable.

Magnesium L-threonate and magnesium malate are energising and should be taken early in the day for maximum benefit. L-threonate has been shown to improve cognitive function, making you feel more alert. Malate is particularly useful for muscle aches and pains.

Magnesium can also be absorbed through the skin (transdermal) with magnesium sulfate (epsom salts), and magnesium chloride. An epsom salt bath alleviates constipation and helps relax the body (great for muscle aches) and mind. Magnesium chloride is a topical spray, best rubbed into the muscle tissue (thigh) after a hot bath or shower, when pores are open.

It supports the nervous system, immunity and soothes achy muscles. Transdermal magnesium is highly absorbable as it by-passes the digestive tract, and thus recommended for everyone to support magnesium intake.

Ingested and transdermal magnesium supplements can be used in conjunction.


In the UK, the RDA for potassium is 3,500mg. Potassium is found in a wide variety of foods, and thus neglected, under the assumption that people have adequate intake. Deficiency can be caused by poor intake, but also by increased excretion though urine and the gastrointestinal tract.

Frequent urination is common symptom of type two diabetes and during the initial stages of nutritional ketosis—two scenarios where there is a greater risk of potassium deficiency.

It is also worth noting that potassium levels can also be compromised by a magnesium deficiency. These two minerals are closely intertwined, and as we know, magnesium deficiency is something that everyone should consider addressing.

Magnesium controls the movement of potassium in and out of the cell and may also assist in absorption. In addition, magnesium deficiency promotes potassium excretion, further diminishing potassium levels. In the absence of magnesium, supplementing with potassium renders itself ineffective for replenishing potassium levels.

If you suspect a potassium deficiency, you may need to first address an associated magnesium deficiency—administration of magnesium and potassium, alongside mineral rich foods, may work well here.

Bananas are instantly associated with potassium, but this high carb fruit is off the low-carb menu. To be honest, it’s a bit bananas as to why this fruit is so glorified for potassium, when so many other foods would rival it. Leafy greens (chard, spinach, beet greens and kale), fish and avocados top the list for rich sources of potassium that would give a banana a good run for its money. Other great sources include mushrooms, hemp seeds, meat, broccoli, milk, tomatoes and almonds.

To make sure potassium levels are in tip top shape, you can supplement with potassium citrate 99mg, along with a good magnesium supplement. Viridian do a combined magnesium, potassium supplement, so you can hit two birds, with the one stone.

Today’s society is conditioned to a ‘keep going, be strong and ignore symptoms’ attitude. It’s not deliberate, but rather we’re so focused on the running of our day to day life, that we don’t hear our body screaming at us when things are imbalanced. Instead, we mask tiredness, poor sleep or depression with caffeine, wine, and chocolate, and just keep going. Sound familiar?

If this resonates with you, I urge you to take notice of your body. Refrain from bandaging the symptom, but rather tackle the root of the problem and address the possibility of electrolyte deficiency.

You might be surprised by how well you can feel and function with just a few simple adjustments. I mean, why not get the most out of your body’s ability, and charge it up with electrolytes!?

If you’re having trouble with electrolytes, or feeling a bit poorly these days, get in touch! Through support and advise, we can help you pinpoint possible deficiencies and help you get on with a healthy, happy life.

Like what you’re hearing?

Stay tuned for more guides, to help you with your health journey.

Ciao 🙌🏽

I’m sure you’re curious about the science behind all this 🔬 Here are some recent medical publications about this topic:



September 8, 2021
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