Using Salt To Optimize Mental & Physical Performance

Key Takeaways

• Conscious and unconscious salt intake and sensing modulates cravings for sugar, water, and other things.

• Sodium is the way your neurons communicate – having enough salt in the body allows the brain and nervous system to function.

• Sodium and water work together in the body: thirst is not just a way to bring fluid into our body – it’s an internal signal telling us to balance salt level.

• “If you’re craving salt, you probably need it.” ­– Dr. Andrew Huberman.

• It’s helpful to have a formula and not just consume salt and water-based on craving because your body tends to adapt to certain levels of salt over time so it doesn’t provide a consistent indicator.

• The notion that a high salt diet is bad for you is confounded by the fact that high salt diets are usually rich in processed foods and a poor balance of carbohydrates to fat.

• There’s a direct relationship between the stress system (glucocorticoid system) and the salt craving system.

• If you’re feeling anxious, slightly increasing sodium intake can stabilize blood pressure and ability to lean into stressors and challenges.

• Galpin equation for fluid replenishment during exercise or cognitively demanding activity: start exercise hydrated with electrolytes (not just water) then every 15 minutes consume (in ounces) your body weight (in pounds) / 30.

• Rule of thumb if you fast or follow time-restricted eating: caffeine is a diuretic so for every ounce of caffeine, drink 1.5x as much water with a touch of sodium.

• Very generalized recommended mineral intake, barring health conditions: 3.2-4.8g of sodium, 4g of potassium.

• It’s critical that you know your blood pressure to make informed decisions about salt and fluid intake – salt needs will vary accordingly.

Brain-Gut Connection & Its Role In Taste

• Neurons activated in the gut are activated when sugar, fatty acids, and amino acids are present.

• Nerve cells (specifically called neuropod cells) in the gut are collecting information about what’s there and send that information up to the brain via the vagus nerve.

• Neuropod cells sense nutrients, particularly sugar, which activates areas of the brain that cause you to seek out more of that food.

• The selective preference for seeking out sweet foods occurs even if you can’t taste the food and it is injected straight into the gut.

• The gut can detect the difference between sweet things that contain calories and things that do not (artificial sweeteners).

• We have salt receptors that fire action potentials when salt is detected.

• The closer foods are to their innate taste (without processing), the more quickly you can hone in on salt appetite and salt needs.

General Functions Of Salt

• Fluid balance: salt regulates how much fluid you desire and how much you excrete.

• Salt appetite: you crave salty things when salt stores are low and avoid salt when stores are high.

• Nutrient appetite: salt regulates appetite for sugar, carbohydrates, and other nutrients.

• Scientifically, table salt and sodium are not the same things – one gram of table salt contains 388 mg of sodium.

Functions Of Salt In The Brain

• We have neurons in the brain that sense the levels of salt in our brain and body.

• The blood-brain barrier prevents substances from entering the brain unless those substances are very small or required for brain function – but there are special areas (organum vasculosum of the lamina terminalis; OVLT) that monitor salt and osmolarity sense contents of blood and salt levels.

• OVLT detects changes to salt levels in bloodstream and sends signaling cascades accordingly – thirst, regulation of blood pressure, kidney function, secretion of salt.

• Types of thirst: (1) osmotic thirst (concentration of salt in the bloodstream); (2) hypovolemic thirst (thirst related to drop in blood pressure).

• The cascades are set off for concentrations of both high and low sodium in the blood.

• Osmotic and hypovolemic thirst are not just about seeking water – they’re also about seeking salt which can help retain water.

• Sodium engages the action potential, which is the firing of electrical signals by neurons.

• If you ingest too much water (this requires A LOT of water), you will actually kill yourself because you’ll disrupt the body’s ability to communicate, brain, and neurons.

Kidneys

• It’s a complicated, highly contextual balance between hormones, salt, and fluid.

• The kidneys are responsible for retaining and releasing substances in the body such as glucose, amino acids, urea, uric acids, salt, potassium, etc..

• Very general mechanism: blood enters the kidney and responds to hormonal signals to make mechanical or chemical changes to retain or release substances accordingly.

• Your urine is filtered blood!

• Vasopressin: anti-diuretic which prevents urination by increasing permeability of distal tubes.

• Water follows salt: the kidney holds on to water in the body when it needs salt.

• When estrogen levels are high, there’s water retention.

Blood Pressure And Salt Intake

• Blood pressure is in part regulated by sodium intake and sodium balance.

• An increase in sodium could help combat symptoms of low blood pressure.

• Historically, we’ve been taught that a high salt diet may be consequential for brain function.

• However, high salt diets are likely related to other unhealthy factors like processed foods, poor balance of carbohydrate and fat, etc..

• A high salt diet can have detrimental health consequences – but – a very low salt diet can also have deleterious health events.

• Some reports point to the idea that diets with more salt than we previously thought necessary, may actually be protective if you find your sweet spot (not too high, not too low).

• Read more: Urinary Sodium and Potassium Excretion and Risk of Cardiovascular Events

• Read more: Dietary Sodium and Health: How Much Is Too Much For Those With Orthostatic Disorders?

• People tend to adapt to certain levels of salt and fluid intake.

Mental & Physical Aspects Of Cravings For Sodium

• There’s a direct relationship between the stress system (glucocorticoid system) and the salt craving system.

• Bringing sodium in the body counteracts or resists stressors in our lives.

• If sodium is too low, our ability to combat stressors is impaired.

• If you’re feeling anxious, slightly increasing sodium intake can stabilize blood pressure and ability to lean into stressors and challenges.

• Additional sodium intake is naturally stimulated by stress.

Other Related Minerals: Potassium

• Sodium and potassium work closely together in the body.

• Recommended ratios of sodium to potassium vary widely.

• Diet is an important contextual element to your ideal sodium-potassium ratio.

• Low carb dieters excrete more water so lose sodium and potassium at a higher rate and may need to adjust dietary intake accordingly.

• If you are time-restricted eating or fasting you may want to consider increasing electrolytes if you ingest caffeine since caffeine is a diuretic.

• Rule of thumb: for every ounce of caffeine, drink 1.5x as much water with a touch of sodium.

Other Related Minerals: Magnesium

• There’s some evidence that supplementing with magnesium malate can reduce muscle soreness