The Salty Truth on Sodium

Carla Rae Nowicki, MS, RD, CSSD, CSCS

September 2017

 

There is a lot of flip-flopping sides when it comes to sodium. Some tout about the amazing benefits of sea salt; claiming that using it daily can help your health, exercise performance, and prevent from nutritional deficiencies. At the same time, others consider it one of the major health risks in America; warning that even as little intake as 2g of it daily is putting you at risk of high blood pressure and heart problems(1). Instead of taking sides, what if I were to tell you that are both right… just in the correct context.

Sodium Sensitivity

It's sometimes really annoying to hear it, but everyone is different. Everyone reacts differently to sodium. Sodium sensitivity is based on how well your body reacts to sodium intake from your diet and the filtration of sodium out of the bloodstream via the kidneys. In a proper system, your body keeps a VERY tight grip on the sodium levels in your blood. When you add extra sodium into your body, your kidneys flush out the majority of it and the rest gets dispersed through your body and cells. This is why when you go out for sushi or go for some Chinese your hands get puffy and you weigh more the next day. You are retaining water and sodium throughout your entire body. Over time, this sodium puff goes down with proper hydration and time.

Some people just didn’t win the sodium genetic lottery. Some of the factors that make you more susceptible to sodium sensitivity are African American descendant, age, or known genetic disposition (1). Gender also might play a role in sensitivity. When decreased sodium intake interventions were tested, females had a significantly different improvement in blood pressure (2).

The Medical Side

The reason medical professionals stress to keep sodium to a minimum is wise for their usual population. Doctors usually see the sick, inactive, and poorly nourished individuals that lack positive sleep habits, setting up for compounding disease states. If you fall under ANY of these categories, YES, keeping your sodium intake low is important. In 2005 it was estimated that about 30% of all deaths were caused by cardiovascular disease globally, and of that hypertension was a major risk factor in 49% of coronary heart disease cases and 62% of strokes (3). These are not statistics to take lightly.

To keep your body working properly (without taking exercise or excess sweating into account), the average person only needs about 200-500mg daily (2,4). Compared to the average person’s intake of 5000mg, that’s minuscule (5) . A recent meta-analysis of 36 studies on the effects of sodium on systolic blood pressure did show that keeping your sodium intake below the recommended 2000mg limit has a significant difference of 3.39mg Hg, but not your diastolic blood pressure (5). Keep in mind that most of the studies that had significant changes were in patients that already had hypertension. There was a very small decrease in blood pressure for those without hypertension (5). It makes a case to wonder if it is mainly the individuals that are susceptible to hypertension that need to take the low sodium recommendations to heart.

What’s going on in your body takes us back to high school science classes. It is partially as simple as solvent/solute concentration gradient. When you eat sodium the first place it gets absorbed to is the bloodstream. From there it irrigates almost all cells in your body. Since your body needs to have a tight regulation on sodium in the bloodstream it gets rid of excess in a couple ways- urination, through cell membranes, and increasing the water content in the blood to dilute the sodium. The last is why blood pressure increases with high sodium intake. More water means more blood volume. This increased volume forces the heart to work harder, pushing against that pressure and increases pressure on all of your artery walls (6).

Sodium and other electrolytes help balance out solute concentrations and communication with cells. Everything from muscle contractions to cellular hydration involves sodium. Without it, cells are not properly hydrated, do not communicate well, and do not function properly.

But where is that sodium coming from? Most sodium-packed foods are coming from processed and fast foods. About 57% of the American intake of sodium comes from packed and processed foods (7). Most of us that are concerned about our health don’t eat a lot of that junk and focus on eating fresh fruits and vegetables. A common recommendation for those trying to lower their blood pressure through diet (8).

Salty Sweat

Salt is a major component to sweat. When it comes to electrolytes, sodium is the start player over potassium, chloride and the rest of the gang. People sweat out anywhere from 500mg-2000mg of sodium an hour when exercising. If you are a heavy sweater, plan on working out in the heat, having additional sodium is necessary to ward off cramping and keep sweating properly.

Like almost every nutrient, the rules are that enough is good, a little extra is great, but above that there is no added benefit and can be toxic. in compared to those who are undersalted, the properly salted individuals do have saltier sweat (9). However, If you are over salted, no additional salt is sweat out (5). However, Your sweat concentrations are mainly based on the environment and your genetics. Some people are salty sweaters. Some companies have come out with really cool wristbands to tell you how much salt you are sweating out. These gadgets are pretty pricey, however (10). One of the easiest ways to tell is how your salt dries. When you sweat and it dries on your skin, those with saltier sweat will end up with that salt crystallizing on their skin. If you feel powdery after sweat dries, you are probably a salty sweater.

During the summer months, it is important to keep a moderate level of sodium intake to account for outdoor activities especially. The danger of not taking in enough sodium with drinking large volumes of water is real. Usually, in amateur endurance athletes, there is always a couple incidences of hyponatremia a year, especially on hot days. To avoid this, any time exercising over 60 minutes, or in the heat, have a beverage containing electrolytes, or just add ¼- ½ tsp of salt into your water bottle.

Not All Salts Are the Same, But They Aren’t That Different

If you go to the salt shelf in the grocery store, you might be surprised of all of the different types of salt out there. The main ones I want to point out are table salt, Himalayan pink salt, and Celtic sea salt. As much as there are major health claims to some, besides the fortification of iodine, there’s not much research to back it up.

Table salt is actually a processed form of salt. It is a cleaned out 99.99% sodium chloride. If salt wasn’t white enough, producers sometimes even bleach the salt to make sure it shines white enough for the public. Whether or not this process is harmful is still up in the air. On a side note, table salt is also fortified with iodine. In the early 1900’s, the US started iodizing salt to combat common iodine deficiencies. It worked and the practice stuck. Over the course of the year that Morton Salt released their iodized salt, the American average IQ increased 15 points in deficient areas, and 3.5 points nationwide. Globally, iodine is one of the top 4 most common deficiencies, even though it is one of the simplest to avoid (11). Thankfully, there has been a recent increase in iodized salt resulting in a decrease of individuals with deficiency.

Even though iodine deficiency has decreased since the introduction of iodized salt, it still might not be enough. Since most of the American salt intake is from processed foods and not iodized salt, there are still recent concerns of deficiency, especially in pregnant and lactating females. Multivitamins are also catching on as a catch-all. Most multivitamins also contain iodine, so if you take a high-quality daily multivitamin, you will most likely don’t have to worry about becoming deficient.

The two that have gotten a lot of recent attention for added health benefit claims are Himalayan pink salt and Celtic sea salt. These salts are collected from areas of high mineral concentrations. The salts are not processed or bleached to get rid of these added minerals. These two types of salts have many health gurus claiming everything from an increased libido to reducing the risk of cancer, but the claims are not backed up by any real research. They are just claims from individuals. For Celtic sea salt, the main added minerals are magnesium, iron, manganese, boron, and silicon. As far as Himalayan pink salt, there is added calcium, chloride, magnesium, and iron. As far as iodine goes, the Himalayan are some of the most iodine-deficient populations in the world. As far as what is considered high, even its highest health claims like iron, there is only about 0.23mg of iron for every teaspoon of salt. This means for females to get their recommended 18mg of iron daily, they would need to take in approximately 78 teaspoons of salt a day, or a whopping 180,000mg of sodium along with that iron.

Along with some of these needed trace minerals, there can be some heavy metals that might hurt you even more than they may help. The Himalayans are particularly high in toxic heavy metals including There are some instances that traces of aluminum, lead and copper (only needed in small amounts) toxins to your body. Again, the chances of them being in high enough doses to hurt you is unlikely.

Take Home Points

·         Those who are not active or have genetic dispositions for sodium sensitivity should be conscious about sodium intake to make sure they do not get too much

·         Those who are active, in hot climates and heavy sweaters should be conscious about their sodium intake to get enough

·         Your body will flush out extra sodium as needed if you are a little over without a lot of stress on your body

·         Himalayan and Celtic salts, while they do have additional trace elements, only have minuscule amounts of trace elements, making their current health claims lacking. There is limited to no real research to also back these claims. You are better off just taking a multivitamin and eating your vegetables.

·         If you don’t take a multivitamin, make sure you use some iodized salt to make sure you get enough. Stay smart.

 

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2.      He, Jiang, Gu D, Chen J, Jaquish CE, Rao DC, H. J. et al. (2010). Gender difference in blood pressure response to dietary sodium intervention in the GenSalt study. Journal of Hypertension, 23(4), 333–336. https://doi.org/10.1016/j.virol.2011.01.029.The

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8.      Pahnke, M. D., Trinity, J. D., Zachwieja, J. J., Stofan, J. R., Hiller, W. D., & Coyle, E. F. (2010). Serum sodium concentration changes are related to fluid balance and sweat sodium loss. Medicine and Science in Sports and Exercise, 42(9), 1669–1674. https://doi.org/10.1249/MSS.0b013e3181d6c72a

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