Why salt is an essential nutrient in the backcountry.
By: Kyle Kamp, RDN, LD. Originally appeared and written for Backcountry Fuel Box.
Sodium is probably one of the first three things you look at on a nutrition label when determining whether some food is going to make the final backpacking list. Salt is a nutrient we need in some amounts on a daily basis for normal bodily functions like muscle contraction and water distribution; however, some circumstances significantly increase our need above normal recommendations; circumstances that are directly related to outdoor recreation.
WHY A HIGHER SODIUM CONTENT IN THE BACKCOUNTRY IS ESSENTIAL
Something that’s baffled me for years as a dietitian focusing on athletes in outdoor recreation is why people avoid sodium in meals and snacks like the plague but will still toss an entire Ziploc bag full of salt tablets into their pack for those “just in case” moments. Whatsmore, when you read their post-trip reports most say those “just in case” happen on nearly every trip.
There are three instances where higher salt intake is more than just ok- it’s essential in backcountry fuel.
The higher the altitude, the less oxygen available to you. As a result, your lungs burn like fire to keep supplying enough oxygen to continue your pursuit. This doesn’t seem like something that would affect salt intake until you take into account that all of those labored breaths equate to fluid loss when you exhale. More fluid loss means a greater need for fluid replacement, and fluid replacement without electrolyte replacement (of which sodium is one) can create a recipe for disaster.
It’s been estimated there is more than an entire day’s worth of a person’s salt needs resting in a Nalgene bottle’s worth of sweat; that is to say there can be between 3,200-4,500mg of salt per liter of sweat. That also happens to be the same amount of salt sitting in 14 medium-sized boxes of your favorite fast-food joints french fries. The summer heat also brings complaints of cramps from many backcountry hunters and hikers. It’s been my experience the finger is usually pointed at potassium as the culprit for cramps, but we’ve found focusing on salt would be a better investment of our time provided it’s the chief electrolyte in sweat.
3. MOVEMENT (EXERCISE)
Waltzing around in the mountains is undoubtedly hard work. No doubt, it’s this bizarre dichotomy of hard work and achievement that keeps us coming back year after year to bag the same peaks, hike the same trails, and plummet into the same canyons all in the name of fun.
Your muscles work incredibly hard to propel you towards whatever goal you’ve got your eye on in the distance. Each quad-burning step produces a significant amount of heat that your body must work to cool with sweat. The harder the climb, the greater the sweat quantity, the higher the sodium losses, the more vital it becomes to replace the losses.
OPTIMAL LEVELS OF SODIUM IN THE BACKCOUNTRY
If you’re like I am and really into the nerdery of nutrition, you’d appreciate a specific recommendation here; however, it’s incredibly difficult for us to establish one firm number given how many variables can be involved in each unique set of circumstances and an individual’s unique biology.
Even with those variables, however, it’s reasonable to suggest you aim for more than the current upper limit of 2,300mg/day when headed out into the backcountry.
WHY DO I FEEL SO TERRIBLE THEN?
When asked why they avoid salt many mountaineers, athletes, hikers, and hunters suggest that many of the high salt foods (dehydrated meals, snacks, etc.) cause them a whole litany of belly issues when in the backcountry.
You can’t argue with the way someone feels, but what may actually be causing all the trouble is a host of other factors and not just the salt in the meals and snacks.
It’s much more likely that the environmental factors of altitude and heat, increased exercise (which results in less blood flow to your gut), and nutrients like fiber, fat, and protein are the reason why your buddy asked “is this bear country?” after mistaking the aftermath of your food choices for bear scat.
THE BRASS TAX
Here’s the reality: you need salt in the backcountry if you want to perform well. Remember, our mantra isn’t just making it to your destination, but enjoying the journey and feeling well enough to sit back and enjoy the view once you get there. Decent salt intake is a must-have part of that equation.