Food Freedom Friday edition 357 - Salt & Sodium

Salt has often been vilified and blamed for contributing to many chronic illnesses including high blood pressure, heart attacks, stroke, and kidney disease. It has even been labelled as ‘the deadliest ingredient in our food supply’. Considering that saturated fat has been the biggest nutritional villain of late, that’s high praise. Most government guidelines set the upper limit of salt at 6 grams per day, which works out at 2.4 grams of sodium. Most people consume more than that.

Table salt contains about 387mg of sodium per 1g serving, creating confusion with some of the numbers. A teaspoon of salt is fine by conventional nutrition recommendations, but a teaspoon of pure sodium is considered dangerous.

Salt has many uses as an essential compound in metabolism.

·       Major component of extracellular fluid

·       Essential for maintaining the plasma needed for tissue perfusion and cellular metabolism

·       Allows neurons to send messages to other neurons, making it an integral part of the nervous system

·       Contributes to the synthesis of HydroChloric Acid (HCL), which helps break down food

A true salt deficiency results in a condition called hyponatremia with symptoms including nausea, headaches, seizures, and coma. It is definitely not a matter of debate whether you need salt. The question becomes how much is necessary and optimal in the human diet.

Salt & Human Evolution

Both the low salt and high salt philosophies have stakes in evolutionary origins.

There are a few claims that humans evolved to seek out salt with tales of early humans following wild animals to salt licks, then setting up camp around those salt deposits. The Aquatic Ape Hypothesis, theorizes that apes became human by hunting fish and invertebrates across wetlands. This theory also argues that ancient humans migrated along bodies of water, keeping it on hand as their main food supply.

There little research supporting this theory as the sodium content of these animals, including catfish, snails, and pondweed, is negligible. A pound catfish contains about 200 mg of sodium, not exactly a large amount for the serving size. There is also better evidence pointing to large-scale hunting of megafauna. Animals that packed on far more calories and were easier to hunt. 

Catching fish tends to be a bit harder than simply poking a stick around. A practical take on hunting would assume humans seek the largest number of calories for the least amount of effort. This is unfortunately why many succumb to the high-calorie, nutrient devoid processed junk of today. However, in the Paleolithic era, this would lead directly to hunting a woolly mammoth.

A study on the diet of ancient man has estimating that pre-agricultural humans ate only about 768 mg of sodium. This is considerably less than the contemporary recommendations. Another study concluded that there is no evidence that paleolithic people sought out salt deposits. With the justified assumption that early humans were hyper carnivores, it stands to reason that the bulk of their sodium intake was derived from the natural contents of meat. There was no licking of salt blocks in between mouthfuls of mammoth steak.

Salt as an additive was likely absent for the vast majority of human existence, until the advent of agriculture. As far back as 6000BC, wars were being fought over salt deposits like the Yuncheng Salt Lake in China. Ancient Egyptians discovered the art of using salt as a preservative. Roman soldiers were sometimes paid in salt, leading to the word ‘salarium’, or ‘salary’. Salt was a critical resource across the globe until relatively recently, transplanted by the arrival of sugar. It is only in this modern era that salt’s reputation has been tarnished.

Modern Salt Controversies

The implication of salt contributing to and even causing high blood pressure was the product of population surveys which appeared to correlate hypertension with higher salt intakes. A rodent study, where rats developed high blood pressure after eating salt added fuel to the fire. This was further supported by the mechanism of sodium, which can redistribute fluid to extracellular space when increased abruptly, thereby increasing blood pressure. These facts created the foundation for government recommendations for salt intake, encumbered by the growing metabolic epidemic and a need to attempt to resolve these health issues.

Although the science may appear looks imposing, the theories and conclusions dissipate on closer inspection. The correlating line was drawn by conveniently including outliers, a sign of bad practice in scientific circles. In reality, the  population survey study showed no evident correlation between high salt intake and hypertension. Regardless, it still managed to get accepted as fact and salt demonization became rampant.

When it comes to the rodent study, they were fed with the human equivalent of 500 grams of salt. Not exactly a dose one would conventionally consume. A sudden spike in dietary salt might cause an initial elevation in extracellular fluids, but that quickly gets negotiated by the kidneys which ramp up their sodium excretion. The effect is negligible after a few days. The body is perfectly capable at handling fluctuations in real, natural ingredients.

Despite the invasion of salt-packed processed foods, there is little solid evidence to incriminate sodium intake as a driving force behind hypertension. In theory, you could take in so much salt that the body begins to shut down. There are even incidences of people committing suicide by drinking heavily salted water. These are, however, extreme cases that are impossible to replicate in any dietary setting.

Contrary to these outdated hypotheses, recent research has begun exposing the dangers of inadequate salt intake. Studies have found a “low-salt zone” in which the incidences of heart attacks, strokes, and death actually increase. The study demonstrated that the lowest risk was found at the drastically higher range of 4 to 6 grams per day A further study found that people on low-salt diets had higher plasma levels of cholesterol and triglycerides. Low-salt has also been linked to the immediate onset of insulin resistance and Type 2 Diabetes. The lower ranges displayed in this study are in alignment with current guidelines recommending a maximum sodium intake of 1,500 mg.

It appears that there is a dose-dependent relationship of salt to health, with the greatest risk being displayed at the low-end. Meanwhile, ‘excessive’ salt intakes only increase risk by a marginal amount. The global consumption of salt over the last few centuries has been in the range of 1.5 to 3 teaspoons per day. This works out at around 3.45g to 6.9g of sodium. This fits rather well with the low-risk zone found in the research.

There are, however, a few variables to consider as they may alter your personal requirements.  

Considerations

Exercise

Hard training depletes sodium through sweat, and endurance athletes are continuously shown to be at risk of hyponatremia. It would be practical and logical to balance the demands of intense training with an extra gram or two of sodium. 

Adding ⅔ of a teaspoon of salt to water consumed whilst exercising or adding in some well-formulated electrolyte mixes (a blend of sodium and other minerals) can help. This is in addition to regular salt intake of 1.5 – 3 teaspoons.

Ketogenic & Low-Carb Diets

Ketosis depletes sodium by increasing aldosterone, which causes the kidneys to excrete sodium. This is especially important in the early stages of fat adaption, where a sodium deficiency can occur, forcing the body to fire up the adrenals to counter the threat. That has the effect of conserving sodium, but also depleting potassium, the mineral which normally balances out high sodium. 

Adding an extra ⅔ of a teaspoon of salt during the first 2-3 weeks of a ketogenic diet, while making sure potassium levels are also being restored is important. A great option is beef which contains approximately 350mg of potassium per 100g serving. A well-formulated electrolyte supplement can be supportive.

Potassium

This vital mineral acts as a counterweight to sodium, helping to reduce blood pressure and water retention. It could be easily argued that hypertension in a high-salt diet may not be due to the salt itself, but rather the lack of potassium to buffer it. A standard Western diet, is packed with refined ingredients and severely lacking in potassium. 

Ensure adequate potassium levels by eating plenty of red meat. This will often mitigate many issues associated with a high-salt diet. Vegetables can also be part of the solution but they are not my favorite recommendation.

Carnivore & Meat-Based Diets

When following an all-meat diet, there is little need to be concerned about getting enough potassium, by virtue of the abundance of red meat. There is, however, a small risk of spiking heart rate by using too much salt. The carnivore cocktail is already a potent stimulant, and when eating in this manner over the long-term, it’s worth trying to minimize adding unnecessary stress. Electrolytes becoming out of balance is a huge stressor

Beef itself has around 80mg of sodium per 100g serving, which lines up with the general recommendation of a 1:3 sodium to potassium ratio. An extra half-teaspoon of salt can be sufficient for optimal blood flow.

Moderate salt works best when following a carnivore diet, adding more in the case of added exercise or the induction period.

Salt Recommendations

·       1.5-3 tsp of salt per day

o   Add ⅔ tsp to minimal requirement for hard exercise

o   Add ⅔ tsp to minimal requirement for keto or carnivore induction

o   Add ⅔-1 tsp of salt per day for carnivore

·       Maintain at least 3500mg of potassium per day, ideally in a 3:1 ratio to sodium.

Personal Salt Needs

It’s impossible to draw a definitive conclusion for optimal salt requirements, due to the number of confounding factors. These include the activities you participate in, as well as amount of potassium it is paired with. It is definitely safe to suggest that the arguments for low-salt diets are unfounded and even downright dangerous. You are better off consuming a little too much, then having too little. 

The majority of the Western world’s sodium intake comes from processed food which also include countless amounts of toxic ingredients such as vegetable oils, plant toxins, and sugars. Remover processed food and what remains creates very little reason for concern.

Excess amounts of sodium can be easily counteracted by the kidney’s ramping up sodium excretion, averting any potential disasters. If anything, the side effects of too much salt are going to be much milder than a dose of hypertension.