Salt - Evil Additive or Essential For Health?

Salt has been a highly valuable commodity throughout the history of mankind — so revered that terms like “worth their salt” are used widely to describe a person’s integrity. Yet today, every newspaper, magazine, and blog seems to be telling us to avoid salt like the plague!

With all the conflicting information, it’s no wonder one of the most common questions I get asked by patients is “should I reduce my salt intake?” It’s now so ingrained in us to search for ways to reduce our salt intake, that many people don’t stop to question their efforts. Is salt really an evil additive that increases the risk of high blood pressure and cardiovascular disease, or is there more to the story?

How Much Salt Should I Consume?

Depending on which health group you talk to, everyone has a different target range for their ideal salt intake. The American Heart Association (AHA) states you should aim for less than 2,300 mg daily to prevent high blood pressure and reduce your risk of cardiovascular disease. It seems logical that if you simply reduce your intake of salt, you could reduce your blood pressure and improve your overall health, but where did these recommendations come from?

In the 1980s, a major worldwide study on the connection between salt intake and blood pressure was conducted, and researchers found that cultures in which sodium intake was low had lower incidences of high blood pressure and cardiovascular disease. Animal studies confirmed that rats fed very high sodium diets rapidly developed high blood pressure and subsequently the “war on salt” began and hasn’t stopped to this day.

However, upon reviewing the latest research, it seems the question still remains unclear.

The research does show that if you already have high blood pressure, you could benefit by lowering your sodium intake.1 But consider the Japanese, who consume the highest amount of salt but also have the lowest incidence of CVD. Japan also has the longest life expectancy of any population on earth. Is salt really to blame for increased blood pressure and cardiovascular risk?

If we look back to our Paleolithic ancestors for answers, we estimate the average sodium intake to be approximately 800 mg, far less than today’s daily consumption of 3,300 mg. However, our hunter-gatherer ancestors also consumed the blood, skin and cartilage of animals where sodium is stored in large quantities. Taking this into account, our hunter-gatherer ancestors likely consumed about 3,000-4,000mg of sodium daily, about the same as we do today. 

 

a very high amount of potassium – approximately 10,000 mg per day – via their abundant intake of lean meats, healthy fats, and veggies. This ratio of sodium-to-potassium is a crucial piece of the “how much salt should I eat” puzzle, and often overlooked when doctors tell patients to restrict their sodium intake.

The Sodium:Potassium Balance

It turns out that our salt consumption in the 18th and 19th centuries was far greater than today and has actually been on the decline since the the 1950s when the "Diet-Heart Hypothesis" came to the forefront and more intensely since the 1970s when the Dietary Guidelines for Americans were released in 1977.  If sodium intake has been dropping since the 1970s, yet rates of hypertension and heart disease have been rapidly on the rise, salt cannot be the culprit. 

On closer inspection, what has changed dramatically is our intake of potassium. Fewer veggies and fruits leads to lower potassium intake, thereby tilting the sodium:potassium ratio in the wrong direction–toward hypertension, cardiovascular disease, and poor health. Increase consumption of diuretics like coffee reduce sodium levels, as well as common prescription medication for blood sugars, high blood pressure and low mood. 

In 2015, a randomly controlled trial (RCT) showed that potassium supplementation helped lower blood pressure 3.9/1.6 mmHg in hypertensive patients.(2) Researchers are also seeing growing evidence supporting the notion that the “sodium-to-potassium ratio” is the superior metric, showing strong associations with blood pressure and cardiovascular disease (versus only addressing individual sodium or potassium levels).(3)

As fruits and veggies are naturally very high in potassium and low in sodium, a diet emphasizing more whole foods will boost potassium levels significantly and keep sodium levels in balance. If you are overweight and have high blood pressure, then restricting processed foods (high in table salt or sodium chloride) and increasing potassium-rich veggies should be your top priority. But what about healthy folks who are active and “eating clean”?

Advice for “Clean Eaters”

If you’re eating cleanly – minimal processed foods, snack foods, and convenience foods – and are active or very active, then the rules of the game are different. In fact, chances are you are NOT getting enough salt! Intense exercise in the gym or training outdoors can lead to significant sweat loss, and subsequently sodium loss, so if you aren’t adding salt to your food you’ll likely be compromising your health and capacity to recover from exercise.

Salt is crucial for increasing absorption of water, preventing muscle cramping, supporting healthy nerve function, blood sugar balance, immune function and the general health of all cells in your body. The risks of not consuming enough salt are significant and rarely discussed.

When we look at the latest research we find that long-term salt restriction can actually increase your risk of heart attack or stroke, elevate triglyceride levels, and in those with blood sugar issues, actually worsen your insulin sensitivity.(4,5) Based on the science, it seems we need to reframe the conversation away from “salt intake” toward “sodium-to-potassium ratio.”

Salt Intake and Overtraining

If you’re an avid Crossfitter, runner, or exerciser then chances are you are losing a lot of salt through sweat. If this persists for too long, you can develop symptoms of over-training due to low sodium status. The problem is this is very difficult to see with traditional medical diagnostics, as the blood levels of sodium will typically remain in the normal range despite the athlete experiencing symptoms of sleep disruption, low mood, and increased thirst and urination — all common symptoms in over-trained athletes.

Both high-intensity exercise and endurance training normally mean more sweat. If you enjoy regular WODs or are training for a triathlon or marathon then salt consumption is critical to recovery and muscular health. You should be adding salt liberally to all your meals and if you experience symptoms of over-training, add an additional electrolyte mix to help replenish sodium and electrolyte levels. If you train in warmer weather, this becomes even more important.

Table Salt vs. Sea Salts

So, what type of salt is best? Regular old table salt, sea salt, or the fancy salts from the Himalayan mountains? Table salt only contains two minerals - sodium and chloride - and is also heavily processed, devoid of important trace minerals, and contains harmful anti-caking additives like sodium silicoaluminate. Table salt does however contain iodine, critical for healthy thyroid function.

Sea salts or Himalayan pink salts naturally contain 50-70+ essential trace minerals and are far superior to add to your diet to improve health and performance. Redmand salt contains the greatest concentration of iodine amongst the sea salts, while Himalayan, Hawaiian and Celtic salts contain lesser amounts iodine. If you struggle with low iodine, your diet should provide the bulk of your iodine intake via seaweed, kelp, etc. Convenient seaweed "snack packs” are also available at health food shops, and it only takes 1-2 seaweed chips per day to get your daily dose.

The Paleo Diet and Salt Intake

If you eat a diet full of convenience foods then you're likely pushing the upper limit of your salt intake, but this is still not the problem. Your lack of potassium intake is what skews your risk factors and increases your likelihood of hypertension. In short, you don't eat enough vegetables, leafy greens and fruit (in moderation). 

By focusing on the “sodium-to-potassium ratio”, rather than simply “salt intake”, it reinforces the importance of eating plenty of vegetables and fruits (in moderation) in your diet. As a general rule, aim for 3-6g of sodium per day and the the cleaner you eat, the more salt you can consider adding to your meals (e.g. aim for higher end of the range).. For active active people. you can be more liberal you can be with your salt consumption to offset sweat. And remember, too much  salt is seldom the problem for most people. Regular table salt is perhaps an evil additive, but natural sea salt - in the form of Himalayan, Celtic, Redmands, Hawaiian, etc - is essential for health, performance and recovery. And the best part is... it tastes great!

 

Dr. Marc Bubbs ND, CISSN, CSCS

REFERENCES
1) Graudal N, Hubeck-Graudal T, Jurgens G. Effects of low-sodium diet vs. high-sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride (Cochrane Review). Am J Hypertens. 2012 Jan;25(1):1-15. doi: 10.1038/ajh.2011.210.
2) Gijsbers L et al. Effects of sodium and potassium supplementation on blood pressure and arterial stiffness: a fully controlled dietary intervention study. J Hum Hypertens.2015 Feb 12.
3) Perez V, Chang E. Sodium-to-potassium ratio and blood pressure, hypertension, and related factors. Adv Nutr. 2014 Nov 14;5(6):712-41.
4) O’Donnell M et al. Urinary sodium and potassium excretion, mortality, and cardiovascular events. N Engl J Med. 2014 Aug 14;371(7):612-23. doi: 10.1056/NEJMoa1311889.
5) Garg R et al. Low-salt diet increases insulin resistance in healthy subjects. Metabolism.2011 Jul;60(7):965-8. doi: 10.1016/j.metabol.2010.09.005.