Quote:
Originally Posted by rubidoux
It is so interesting to me that you and your mother don't eat much salt even though it seems like you're on the salt-deficient side of things. I read an article a while back that said that studies have shown that all over the world people eat very similar levels of salt (on average, I believe individuals didn't all fall in at the same level) and it's believed that we have some mechanism that causes us, as individuals, to eat what we need to keep our levels steady and at the right levels.
There've also been many studies that have found that the more salt you eat, the more salt you want. So I think there may be some truth to a "biological drive for adequate salt intake," but that's assuming a person has access to, and is eating relatively whole, unadulturated, natural foods and not ingesting other non-natural chemicals. Once substances not found in nature, such as medications, processed foods, and table salt enter the equation, you can't rely on those physiological mechanisms anymore. And of course, when you're not following your natural instincts because you've been told NOT TO, that also changes the ballgame.
If my mother and I weren't on blood pressure medications, no doubt our sodium intake would be adequate. When I first had to take the sodium supplements, my doctor at the time told me that blood pressure medications either wash sodium or potassium out of the blood. Because the SAD (standard american diet) is much higher in sodium than potassium, most blood pressure medications are potassium-sparing rather than sodium-sparing.
In addition to the medications, we've both dieted most of our lives - and current diet culture (at least over the past 35 years) advocates drinking far more water than we'd naturally want to. My mom's water intoxication was directly linked to the fact that her WW leader told her that she had to compensate for every cup of coffee with TWO cups of additional water. Mom was only drinking about a gallon of liquids a day, but it was enough to deplete her sodium levels over time.
The kidney specialist called in (because water intoxication damages the kidneys), said he's seeing more and more cases of water intoxication because of dieting water myths. At one time, he said it was rare for even kidney specialists to see more than one case of water poisioning in a career, now even general practitioners are seeing it - and not just in the usual patients (extreme athletes, mentally ill with OCD water drinking compulsion, and people trying to wash illegal drugs from their system for a drug screen).
He pointed out that if coffee were that dehydrating, that people who drink only coffee (and there are plenty of them) would die of dehydration, and they don't. He pointed out (in argument against the water-only advocates) that in the Middle Ages no one drank water, because water wasn't safe. Adults and even children met their fluid needs through foods and soup and beer (because the water for both were boiled, but the people didn't know about boiling water).
In a natural world, when we're following our instincts and the good example of people around us following thousands if not millions of years of tradition - I think we do tend to eat what we need - but our current diet and lifestyles (and the beliefs that guide them) are so far from natural, that we can't rely on those instincts - especially since we don't eat foods we would if we had to rely on a natural diet (insects, all parts of the animal including organ meats, blood, bone, and skin, and tons of plants that we consider weeds and twigs).
Many years ago, there was a study done that found that toddlers given access to a wide variety of foods, allowed to eat whatever they chose, chose a balanced diet. That study was used to argue that humans had an instinct for a balanced diet.
Modern studies however found this only to be true when natural, whole foods were offerred (as was done in the original study). When "junk food" and processed foods enter the mix - babies don't choose a varied, balanced diet - they choose the processed foods (the addictive flavor combination David Kessler describes in his book The End of Overeating - sugar or starch/fat/salt).
When you combine the flavor/food combination of carbs/fat/salt, people tend to eat far more than they would otherwise (Kessler calls it "conditioned hypereating").
To some degree, humans have always gravitated towards this flavor combination in "celebration foods," but historically they were expensive and difficult to obtain and prepare. People had to work very hard (expend a lot of energy) to acquire these foods, so they were never a large part of the diet).
We've created such an artificial world that are instincts don't work well in it.