If you’re reading this, please raise your hand if you’ve heard the phrase “Americans eat too much salt” or, alternatively, that we should “cut back our salt intake”? Show of hands? Ah, yes- seems like everyone has heard that or even possibly said that perhaps.
However, what does the evidence say about salt intake and chronic disease? The current World Health Organization’s (WHO) recommendation is that we take in 2000-2400mg of sodium per day, with some organizations like the American Heart Association suggesting that we should take in <2000mg of sodium per day. For reference, sodium and salt are not the same thing- 1 gram of salt has 400mg sodium.
Briefly, salt is made up of both sodium and chloride so salt intake is not equivalent to sodium intake. For context, the average daily sodium intake in the US is ~3400mg per day, which is about 7-10g of salt per day from all dietary sources combined. Interestingly, sea salt tends to have about 10% as much sodium in it as table salt- though admittedly there are many different formulations available and different concentrations. One could argue that sea salt is not a good “salt-substitute” and that, potentially anyway- we don’t need to be substituting for salt anyway.
The Institutes of Medicine (IOM)- now termed the National Academy of Medicine, one of the big public health recommendation organizations, did a review in 2013 and concluded that
“The evidence from studies on direct health outcomes was insufficient and inconsistent regarding an association between sodium intake below 2,300 mg per day and benefit or risk of CVD outcomes (including stroke and CVD mortality) or all-cause mortality in the general U.S. population.”
Basically, there is no good evidence to support the WHO’s recommendation for the general population. Interestingly, there are additional studies reviewed by the IOM in their analysis that suggested potentially negative outcomes to eating too little sodium. An editorial comment on the review remarks:
“The evidence supports a strong association of sodium with BP and cardiovascular disease events in hypertensive individuals, the elderly, and those who consume > 6 g/d of sodium. However, there is no association of sodium with clinical events at 3 to 6 g/day and a paradoxical higher rate of events at < 3 g/day.”
In short, it looks like there’s a sweet spot of sodium intake at 3-6g/day, which is basically where most Americans fall into. Athletes are a whole different story too, as sodium losses from vigorous exercise can exceed 17g per day. That would require on the order of 30+ gallons of Gatorade to replace, but because the sodium concentration is diluted by all the fluid, this can cause worsening hyponatremia (low salt in the blood) and be fatal, as evidenced by two HS football players who died this past year from trying to replace salt with tons of Gatorade.
The current recommendation by the American College of Sports Medicine (ACSM) is to take 500-700mg of sodium per liter of fluid pre and post workout, which seems about right to me for a good place to start- though this needs to be modified for the individual. It appears that most who train seriously will become hyponatremic (have low salt as measured by blood tests)- though asymptomatic– after training and this may alter future performance. This is especially true for those who do not eat a lot of processed foods, as their sodium intake is lower to begin with.
There also appears to be some performance benefit by replacing salt appropriately, though this is most certainly not with pills, Gatorade or similar, or La Croix…lol. Think more like bouillon cube or salting most meals that are consumed, which effectively deals with this nicely in folks who train once daily.
It should be stated that some with high blood pressure (e.g. the salt sensitive folks), those with congestive heart failure, or other cardiovascular abnormalities should know the above does not necessarily apply to them.
Overall, this whole topic is filled with lots of caveats and interesting points. My main takeaway is that for a non hypertensive, non CHF patient, who eats a diet composed of minimally processed foods- they would likely be better served by adding table salt to most meals and their pre and post workout nutrition.