The science of salt and electrolytes (are we consuming enough?)
Modern science has revealed that we were wrong (and fooled) yet again. As it turns out, mineral deficiencies are likely more of a problem than we realize, as not consuming enough salt and electrolytes is both easy to do and dangerous for our health.
First, the JAMA Internal Medicine exposed last year that the sugar industry literally paid scientists in the 1960s to shift the blame from sugar to saturated fat & cholesterol as underlying causes of heart disease.
Most notably, the political influence of scientists such as Frederick M. Allen, Walter Kempner, Lewis K. Dahl, George Meneely, and Harold Battarbee set a course in the 20th century that resulted in low-salt dogma that made its way into the 1977 Dietary Goals and, ultimately, into the 1980 Dietary Guidelines that have influenced us ever since:
…the 1977 Dietary Goals mainly relied on George Meneely and Harold Battarbee for recommending low-salt to all Americans. However, even these authors believed that salt restriction was only important in those who had a low intake of potassium and only in those who were genetically susceptible to the blood-pressure-raising effects of salt. In other words, even these authors never believed that all Americans should be given low-salt dietary advice.
Uh oh. Houston, we have a problem:
My goal in this article is to teach the underlying science of sodium and other electrolytes as they relate to human health.
I’ll point to research that suggests that the “low-salt” movement is likely causing more harm than good, and I’ll discuss dietary techniques that can guide you toward overall electrolyte nutrition.
Of course, please consult with your doctor/medical team before making any changes to your diet. I’d encourage you to study, share, and discuss the cited research with them as you refine a plan for your ongoing health.
What are salt and electrolytes, exactly?
Technically, a “salt” is any substance that contains a combination of charged particles called cations (positively charged) and anions (negatively charged).
These individual particles are known as “electrolytes” because they can conduct electricity when “separated” (Greek: lytós) in water. Electrolytes can be individual elements (e.g. sodium) or groups of elements (e.g. phosphate).
What we typically call “salt” is actually “table salt” (NaCl); a sodium atom bound to a chloride atom that easily comes apart in water.
What electrolytes are important for human health?
In our bodies there are seven major electrolytes:
- Sodium (Na)
- Chloride (Cl)
- Potassium (K)
- Magnesium (Mg)
- Calcium (Ca)
- Phosphate (HPO4)
- Bicarbonate (HCO3)
The other notable electrolytes are zinc, iron, manganese, molybdenum, copper, and chromium.
To answer this question thoroughly, in fact, let’s look at a Periodic Table and note all the individual elements that we need in our bodies:
Since 96.2% of our body weight comes from oxygen, carbon, hydrogen, and nitrogen alone, that means that 3.8% of our weight comes from all of the other elements noted above. Most of these elements are (or are included in) electrolytes and play vital roles in millions of chemical processes that occur in our bodies every day.
Does too much sodium cause high blood pressure?
This is the million dollar question (or more like a multi-trillion dollar one). As it turns out, there is no conclusive scientific evidence that an over-consumption of sodium causes high blood pressure in the majority of people. There is, of course, tons of research attempting to show correlation between the two; but even then, for those with normal blood-pressure (i.e. less than 120/80 mmHg), there is little-to-no correlation. Even for those with hypertension already (!), there is only a minor correlation, and even then for only 45% of that population.
What!? We’ve been told all our lives that eating a low amount of salt is important for health.
“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, Boston University School of Medicine
Even so — as any good scientist will tell you — correlation (in any direction) does not equal causation.
Is it possible that something else besides salt is problematic in the food that people with blood pressure issues consume? Could that ingredient actually be causing the high blood pressure, or could it be a complex mixture of multiple ingredients? (Spoiler alert: it looks like carbs are the key problem)
Here’s what we know
There is good evidence that a low-sodium diet causes:
- an increased heart rate
- increased stress on the kidneys (i.e. it costs energy to pull salt back into your body vs. just dumping it out in your urine)
- increased insulin secretion, fat storage, and insulin resistance
- reduced fertility
- increased triglycerides, cholesterol, and adrenaline levels
- increased total cholesterol to HDL ratio
- hardening of the arteries in mice (not yet tested in humans, but the evidence doesn’t look good for us)
- increased hematocrit (i.e. the volume of red blood cells over the total volume of blood), aka polycythemia, which can cause easy bleeding, easy bruising, itching, fatigue, and blood clot problems.
- increased renin and aldosterone (which increases blood pressure)
- increased fatty acid synthesis in the liver (which can cause fatty liver disease)
You have to ask yourself then, for everyone — including the small population of people where low-salt diets reduce some blood pressure — are the risks worth it?
What about the other electrolytes? How do I know if I have a problem?
Symptoms of electrolyte imbalances include one or more of the following:
- Muscle aches, spasms, twitches and weakness
- Frequent headaches
- Abnormally large thirst
- Heart palpitations (irregular heartbeats)
- Digestive issues like cramps, constipation, or diarrhea
- Confusion and trouble concentrating
- Bone disorders
- Joint pain
- Significant changes in appetite or body weight
- Fatigue (including chronic fatigue syndrome)
- Numbness and pain in joints
- Dizziness, especially when standing up suddenly
For those interested, I’ve included detailed information in Appendix A below about the 13 notable electrolytes in the human body, including symptoms of too much or too little in your system.
How much of these electrolytes should I be consuming every day?
Here are the current FDA guidelines (I’ll comment more about sodium below; the others aren’t as controversial):
- Sodium: 2,400mg* (changing to 2,300mg in July 2018)
- Chloride: 3,400mg
- Potassium: 3,500mg
- Magnesium: 400mg
- Calcium: 1,000mg
- Phosphate (from Phosphorous: 1,000mg)
- Bicarbonate: (from H20 and CO2 via carbonic anhydrase)
- Zinc: 15mg
- Iron: 18mg
- Manganese: 2mg
- Molybdenum: 75μg (micrograms, aka mcg)
- Copper: 2mg
- Chromium: 120μg
*Scientific evidence suggests this may be harmfully low for most people. Based on a study of over 100k people across 17 countries, “an estimated sodium intake between 3 g per day and 6 g per day was associated with a lower risk of death and cardiovascular events than either a higher or lower estimated level of sodium intake.” Another study looked at ~275k people and found that between 2,645mg and 4,945mg of sodium per day was the optimal range.
Therefore, based on the data above, you may want to discuss with your doctor a plan to consume sodium in the ~3–6g/day range, especially if you are not hypertensive.
Thankfully, odds are if you haven’t been paying much attention to how much salt you consume, as long as you aren’t gorging yourself on tons of processed foods, you are likely naturally consuming about 3–6g/day anyway. Your body knows what it needs.
Outside of sodium, however, there is serious cause for concern that Americans aren’t consuming enough potassium, magnesium, calcium, zinc, and iron.
This may be due to the depletion of these minerals in the soil that grows our fruits and vegetables, the massive decline in milk consumption and beef intake over the past 30 years, and/or the fact that most people have trouble consuming leafy greens (especially spinach) on a regular basis.
In fact, it’s worth diving into each of these electrolytes to get a better idea how much you need to eat to meet the guidelines. In Appendix B below, I’ve included an extensive list of healthy foods to eat in order to get enough of these minerals in your diet.
How do doctors test for electrolyte problems?
The most common way to test for electrolyte imbalances is, of course, blood tests. Most normal lab tests check for sodium, potassium, chloride, calcium, and bicarbonate in your blood serum, but unless you or your doctor specifically ask for it, rarely will you get results about the other electrolytes.
Since minor electrolyte deficiencies and imbalances often result in a general lack of energy (and since most american adults mask these symptoms with caffeine), it’s common for electrolyte problems to go untreated.
Furthermore, calcium, potassium, and magnesium, for example, can appear normal in routine blood serum tests, but actually be low inside cells and interstitial spaces in our bodies. To address this issue, other tests include:
- Red Blood Cell (RBC) Tests — i.e. testing electrolytes inside red blood cells themselves, rather than just blood serum.
- EXA tests — which take a cheek swap and measure electrolytes from that soft tissue, where elements like magnesium are more commonly found.
- Tolerance (or load) testing — this involves injecting someone with a safe dose of the electrolyte, then measuring output in urine.
- Ionized tests — these tests isolate only the “free ions” of the electrolyte in the blood (i.e. the most important for many biological processes), whereas normal serum tests pick up all forms, including those bound to other elements or molecules.
Needless to say, if you suspect an electrolyte imbalance and it’s not showing up in blood serum tests, urge your doctor to run additional tests.
How much sodium do we lose when we workout or sweat for long periods of time?
This is an important question, since the 3–6g of daily sodium intake values noted in the studies above do not account for signifiant levels of exercise or sweating (e.g. working outside in hot climates).
It’s been showed that working a full shift in a hot climate can result in losing up to 6g of sodium in a day. In fact, since there is around 1g of sodium in 0.5lbs of sweat in an average person (which varies greatly depending on what shape you are in and how acclimated to the climate you are), and it’s common to lose about a pound (or more) of sweat in an hour of working out, this means an average non-athlete can lose well more than 2g of sodium in a typical workout. Even well-conditioned athletes have been shown to lose between 409mg and 1,248mg of sodium per hour, depending on the quantity of sweat lost.
Therefore, it’s critical for people sweating to replenish sodium levels accordingly to maintain proper hydration (e.g. 2g of extra sodium per hour of working out). It’s unfortunately common for endurance athletes — or people new to hot climates — to suffer from hyponatremia (i.e. low-salt, a very serious condition), even if they have been drinking plenty of water. In fact, drinking too much water without consuming sodium can cause hyponatremia, since it dilutes the concentration of what little salt is left in the body.
Do we also lose other electrolytes in our sweat?
Yes, though not as much as sodium in proportion to the recommended daily values. One study of 113 people found that the mean losses of iodine, sodium, potassium, and calcium in sweat following a 1-hr game were 52 micrograms, 1,896 mg, 248 mg, and 20 mg, respectively (iodine deficiency, in fact, became a concern amongst the participants). Another study recommended that athletes should consume 10–20% extra magnesium per day, as both male and female athletes were more susceptible to deficiencies versus those who don’t sweat as much.
Long story short, a diverse supplementation of electrolytes is needed if you sweat. These should be considered above the recommended daily intakes.
Why do low-carb dieters (especially those going into ketosis) need to consume an extra quantity of electrolytes?
If you’ve studied any amount of low-carb dieting, then hopefully you’ve come across advice suggesting an increase in electrolyte consumption. This is important.
The more carbohydrates you consume in your diet, the less additional electrolytes you need. This is because dropping carbs results in a lower amount of insulin and a greater amount glucagon in your blood, which signals to your kidneys to dump electrolytes (notably, sodium), which lowers blood volume and can increase heart rate (plus all the other low-salt symptoms listed above and in Appendix A).
This is also aligns with evidence that high-carb diets, not high-salt diet (although they are often correlated), causes hypertension and can lead to obesity and various diseases of the heart.
Do electrolyte imbalances play a role in hangovers?
Yes they do. Not only does alcohol inhibit anti-diuretic hormone (ADH) secretion (which makes you urinate more often and lose water), but your liver requires an arsenal of electrolytes across the board in order to properly detox the ethanol. Thus, a solid diversity of electrolytes (and other vitamin/nutrients) are needed, along with plenty of water, to speed up recovery.
What is the best way to practically keep electrolytes in balance throughout the week?
In Appendix B below I’ve included a long list of nutrient-rich foods to consider across the span of notable electrolytes. That being said, it’s easy to see that, especially for someone who works out and/or sweats regularly, that it’s very difficult to meet the recommended guidelines for most electrolytes (especially potassium and magnesium). You can use an app like MyFitnessPal to track approximately how many electrolytes you are consuming per day (and you’ll see how hard it is).
Therefore, in addition to consuming a fair amount avocados, nuts, and spinach (mixing up both raw and cooked forms) on a regular basis, as I mentioned above, I’d highly recommend discussing with your doctor a high-quality daily supplement regime. With our food sources in the USA containing less nutrients than before (even “whole foods” like fruits and vegetables), it’s difficult to put together a plan to consume a sufficient amount of electrotypes to meet even basic health conditions.
Furthermore, if you workout regularly, you may want to consider direct electrolyte pill supplementation (I use Rapid Rehydr8 as a general purpose mixture, and Doctor’s Best for high-adsorption magnesium). Anecdotally, I’ve found that consuming both water and electrotypes before a workout results in significantly greater performance (research also backs this up).
Finally, it’s helpful to have a diversity of salts in your kitchen (e.g. garlic salt, Himalayan Salt, Redmond Real Salt, Celtic Sea Salt, etc..), as many other elements beyond sodium and chloride can be found in them to round out your electrolyte intake (plus, the nuanced flavors are amazing, you won’t be disappointed).
Author’s note: thanks in advance for any/all feedback, corrections, and comments to this article. I’ve personally experienced dramatic health benefits by paying close attention to electrolyte levels (especially sodium, potassium, and magnesium), and I hope this article helps you do the same. Subscribe to my newsletter and I’ll let you know when I write more about health and fitness topics (I also write about entrepreneurship, blockchain technology, and other science/tech topics). For those interested in additional reading about sodium in particular, I’d highly recommend Dr. James DiNicolantonio’s insightful book The Salt Fix. And last but not least, remember to comment (which you can also do inline by highlighting something), hit the clap button, and/or share this article with a friend if you’ve found it helpful. Thanks!
Appendix A: Detailed information about the 13 notable electrolytes in the human body
- Sodium is primarily responsible for fluid control in the body, and thus helps regulate the concentration of all other electrolytes. It is also involved in nerve and muscle function. Too little sodium is indicated by dizziness, lethargy, confusion, and nausea. Too much causes muscle twitches and seizures.
- Chloride is critical for the electrical neutrality of most fluids in the body (especially extracellular fluid), and also helps control water levels. Too much or too little chloride is evidenced by excessive fatigue, muscle weakness, breathing problems, frequent vomiting, prolonged diarrhea, excessive thirst, or high blood pressure.
- Potassium is most critical for ensuring an electrical potential inside cells so muscle and nerve tissue operates correctly (it does not play much of a role in regulating fluid volume). Symptoms of low or high potassium include weakness, tiredness, or cramping in arm or leg muscles, tingling or numbness, nausea/vomiting, abdominal cramping, bloating, constipation, and heart palpitations.
- Magnesium is critical for hundreds of biochemical reactions in the body, and it also plays a key role in nerve, muscle, and bone function. It’s extremely rare to have too much magnesium given how efficient the body is at excreting it, but too little can cause muscle spasms and cramps, anxiety & depression, high blood pressure/hypertension, hormone & sleep issues, and — most notably — low energy.
- Calcium is critical for transmitting nerve impulses, muscle contractions, and, of course, maintaining bone integrity. Too little calcium can result in muscle cramps, confusion, and tingling in the lips and fingers. Too much leads to increased thirst and urination, belly pain, nausea, bone pain, muscle weakness, confusion, and fatigue.
- Phosphate is the critical anion that balances out calcium and is critical for energy production as well as bone integrity and function. Too little phosphate results in joint pain, weakened bones, fatigue and irregular breathing. Too much leads to similar symptoms as too little calcium (i.e. muscle cramps, confusion, and tingling in the lips and fingers).
- Bicarbonate is the key buffer of pH in your body. In response to increased acidity (e.g. lactic acid build up after working out), the kidneys secrete bicarbonate to lower blood pH. On the flip side, if the blood becomes too basic, the kidneys will slow bicarbonate release. Symptoms of high bicarbonate include confusion, hand tremors, lightheadedness, muscle twitching, nausea, vomiting, numbness or tingling in the face/hands/feet, and prolonged muscle spasms (tetany). Too low bicarbonate increases blood acidity and results in rapid and shallow breathing, confusion, fatigue, headaches, sleepiness, lack of appetite, jaundice, and an increased heart rate.
- Zinc plays a variety of roles in wound healing, protein formation, and — most notably — the immune system. Too little zinc results in poor memory, a weakened immune system, constant onset of colds, loss of taste or smell, sleep problems (zinc is needed to make melatonin), hair loss, loss of appetite, low libido, and diarrhea. Too much leads to abdominal cramps, nausea, vomiting, diarrhea, stomach irritation, headaches, irritability, fatigue, and/or dizziness.
- Iron is essential for proper blood formation, the distribution of oxygen throughout the body, and thousands of chemical processes essential for your health. Low iron causes dizziness, fatigue, lightheadedness, palpitations, and breathing problems. Too much iron leads to chronic fatigue, joint pain, abdominal pain, liver disease, diabetes, palpitations, sever heart problems, and skin color changes (bronze or green-ish).
- Manganese is a utility player involved in a wide variety of roles, including proper function of connective tissue, bones, blood clotting factors, the creation of sex hormones, blood sugar regulation, calcium absorption, fat & carbohydrate metabolism, and brain/nerve function. Too much can result in neurological disorder (manganism) with symptoms including tremors, trouble walking, and spasms in muscles of the face. These symptoms are often preceded by irritability, aggressiveness, and even hallucinations. Too low manganese, on the other hand, causes weak bones (osteoporosis), anemia, chronic fatigue syndrome, low immunity and frequently getting sick, worsened symptoms of premenstrual syndrome (PMS), hormonal imbalances, impaired glucose sensitivity, and/or changes in digestion and appetite.
- Molybdenum serves as a catalyst for a variety of reactions involving amino acids, nitrogen, uric acid, sulfites, and antioxidants in our bodies. Too much and you can experience severe diarrhea, gout, skin problems, hair loss, growth retardation, osteoporosis, thyroid abnormality, bone and joint abnormalities, and/or significant (not healthy) weight loss. Too little — which is extremely rare — can lead to sulfite sensitivity, an increased breathing or heart rate, low libido, night blindness, and/or mouth and gum disorders.
- Copper is involving in reducing free radicals in the body, making collagen for healthy connective tissue, and producing red blood cells, nerve cells, and immune cells. Too much copper in your system (which is more common for females due to estrogen’s ability to retain it) includes physical fatigue, mind racing, extreme emotional highs and lows, anxiety, and/or reproductive problems. Too little copper can result in fatigue, arthritis, osteoporosis, paleness, low body temperature (i.e. often feeling cold), anemia, and/or frequently getting sick due to the suppressed immune system.
- Chromium is involved in a variety of processes involving the metabolism of fats, carbs, and proteins. Notably, chromium helps regulate blood sugar levels by working with insulin to transport glucose across cell membranes. Too little can lead to poor blood glucose control, bone problems, low energy, skin problems, cholesterol problems, vision issues, wound healing slowness, and/or heart complications. Too much can result in nausea, vomiting, diarrhea, fever, renal failure, severe gastrointestinal irritation, and/or ulcers.
Appendix B: How to consume sufficient potassium, magnesium, calcium, zinc, and iron
How to consume 3,500mg of potassium per day
It’s harder than you think. Foods that will help you consume enough potassium include:
- Avocado: 1 whole: 1,067 milligrams (30 percent DV)
- Acorn squash: 1 cup: 896 milligrams (26 percent DV)
- Spinach: 1 cup cooked: 839 milligrams (24 percent DV)
- Sweet potato: 1 large: 855 milligrams (24 percent DV)
- Wild-caught salmon: ½ filet: 772 milligrams (22 percent DV)
- Dried apricots: ½ cup: 756 milligrams (22 percent DV)
- Pomegranate: 1 whole: 667 milligrams (19 percent DV)
- Coconut water: 1 cup: 600 milligrams (17 percent DV)
- White beans: ½ cup: 502 mg (15 percent DV)
- Banana: 1 large: 487 milligrams (14 percent DV)
A longer list can be found here. Long story short, most people likely aren’t consuming enough potassium, which could explain — in part — why most people feel generally tired (and cover it up with caffeine consumption).
How to consume 400mg of magnesium per day
Similar to potassium, magnesium is also difficult for most Americans to consume in adequate amounts. Foods high in magnesium include:
- Spinach — 1 cup: 157 milligrams (40% DV)
- Chard — 1 cup: 154 milligrams (38% DV)
- Pumpkin seeds — 1/8 cup: 92 milligrams (23% DV)
- Yogurt or Kefir — 1 cup: 50 milligrams (13% DV)
- Almonds — 1 ounce: 80 milligrams (20% DV)
- Black Beans — ½ cup: 60 milligrams (15% DV)
- Avocado — 1 medium: 58 milligrams (15% DV)
- Figs — ½ cup: 50 milligrams (13% DV)
- Dark Chocolate — 1 square: 95 milligrams (24% DV)
- Banana — 1 medium: 32 milligrams (8% DV)
A more extensive list can be found here. Deficiencies in magnesium cause tiredness, anxiety, depression, and sleep problems…which may explain a few things for the typical american adult.
How to consume 1000mg of calcium per day
1) Raw Milk: 1 cup: 300 mg (30% DV)
2) Kale (cooked): 1 cup: 245 mg (24% DV)
3) Sardines (with bones): 2 ounces: 217 mg (21% DV)
4) Yogurt or Kefir: 6 oz: 300 mg (30% DV)
5) Broccoli: 1 ½ cup cooked: 93 mg (9% DV)
6) Watercress: 1 cup: 41 mg (4% DV)
7) Cheese: 1 oz: 224 mg (22% DV)
8) Bok Choy: 1 cup: 74 mg (7% DV)
9) Okra: 1 cup: 82 mg (8% DV)
10) Almonds: 1 oz: 76 mg (8% DV)
A more exhaustive list can be found here.
How to consume 15mg of zinc per day
Thankfully, at least in the USA, zinc tends to easier than other electrolytes to get enough of in your diet, especially if you aren’t a vegetarian (i.e. beef, pork, and seafood have fair amounts of zinc, especially oysters, lobster, and crab). That being said, zinc deficiencies do continue to be a problem worldwide.
Other food sources especially high in zinc include:
1. Lamb: 3 ounces: 6.7 milligrams (45 percent DV)
2. Pumpkin Seeds: 1 cup: 6.6 milligrams (44 percent DV)
3. Grass-Fed Beef: 100 grams: 4.5 milligrams (30 percent DV)
4. Chickpeas (Garbanzo Beans): 1 cup: 2.5 milligras (17 percent DV)
5. Cocoa Powder: 1 ounce: 1.9 milligrams (13 percent DV)
6. Cashews: 1 ounce: 1.6 milligrams (11 percent DV)
7. Kefir or Yogurt: 1 cup: 1.4 milligrams (10 percent DV) (values vary)
8. Mushrooms: 1 cup: 1.4 milligrams (9 percent DV)
9. Spinach: 1 cup: 1.4 milligrams (9 percent DV)
10. Chicken: 100 grams: 1 milligram (7 percent DV)
A more extensive list can be found here. If you find yourself in seasons where you are getting sick more often, consider upping the consumption of zinc-rich food.
How to consume 18mg of iron per day
If you often get tired in the middle of the day and/or feel lightheaded often, a slight (or significant) iron deficiency could be your problem. Foods high in iron include:
1. Spirulina: 1 ounce: 8 milligrams of iron (44 percent DV)
2) Liver: 3 ounces of organic beef liver: 4.05 milligrams of iron (22.5 percent DV)
3) Grass-Fed Beef: One lean grass-fed strip steak (214 grams): 4 milligrams of iron (22 percent DV)
4) Lentils: ½ cup: 3.3 milligrams of iron (20.4 percent DV)
5) Dark Chocolate: 1 ounce: 3.3 milligrams iron (19 percent DV)
6) Spinach: ½ cup cooked: 3.2 milligrams (17.8 percent DV)
7) Sardines: 1/4 cup: 1.8 milligrams (10 percent DV)
8) Black beans: ½ cup: 1.8 milligrams (10 percent DV)
9) Pistachios: 1 ounce: 1.1 milligrams (6.1 percent DV)
10) Raisins: 1/4 cup: 1.1 milligrams (6.1 percent DV)
A more extensive list can be found here. Similar to zinc, if a sufficient amount and variety of beef/pork/chicken is consumed, or vegetables such as spinach, you should be getting enough iron in your system to maintain health.
Thanks for reading! Subscribe to my newsletter and I’ll let you know when I write more about health and fitness topics (I also write about entrepreneurship, blockchain technology, and other science/tech topics). Remember to comment below, hit the clap button, and/or share this article with a friend if you’ve found it helpful. Thanks!