I've been spending a lot of time lately reading scientific papers dealing with nutrient absorption/interaction and I figured I ought to take a gander at the periodic table to see if there are any patterns, and sure enough the elements that are grouped together in a row tend to use the same transport channels.
So, I've found studies that show that Cu, Zn and Fe compete for absorption and also another one that stated that as far as the intestines are concerned, Fe and Mn were the same thing, but I actually think that the whole row of Cr, Mn, Fe, Co, Ni, Cu and Zn all compete for absorption. Similarly, Na, Mg, K and Ca interact. The interactions are sometimes with regard to excretion as well as absorption, i.e. for every 1g of Na excreted in urine per day, there's about 25mg of Ca excreted with it. This would be somewhat significant for someone eating evolutionarily appropriate amounts of Ca alongside SAD-level amounts of sodium.
Anyway, this is of course irrelevant for a HG eating a balanced diet (using a real rather than SAD metric) comprised of Food, since the abundance of elements in the diet will match their physiological need. We're simply not going to evolve to have a need that can't be satisfied. However, for those of us coming to an ancestral diet from one of the various suboptimal ones, we have the issue of how best to address our deficiencies in as rapid a manner as possible. If we simply eat a lot of nutrient dense foods, over time we will become elementally replete in general. Sometimes you want to reach that goal sooner, so you supplement, but care needs to be taken that the supplementation doesn't exacerbate or prolong your other deficiencies.
If you target, say, a zinc deficiency, you're going to want to isolate that supplementation (whether it's a pill or a tin of oysters) from the rest of your diet so it doesn't saturate the transport channels to the detriment of everything else grouped with it mentioned above. I take zinc on an empty stomach a few hours before I eat breakfast, so its absorption is segregated. The absorptive interactions are transitory in nature and probably have a curve with a peak around an hour. Many of you guys are fasting anyway, so by the time you eat, the intestinal environment has been reset to default and the meal can be absorbed fully. One potential problem is intolerance of a particular form on an empty stomach vs. with a meal. This can either be addressed with a food that can be considered non-nutritive in terms of its trace minerals or with a form of the supplement that may not have the best absorption but which doesn't lead to nausea.
asked byTravis_Culp (39831)
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on September 27, 2011
at 01:35 AM
The table is organized in terms of atomic weight and valence, and further split into groups based on properties. The number of electrons in their outer shell does show a pattern. These electrons are the element's valence: that is how readily they will react with hydrogen atoms.
This is why Helium and Hydrogen are on opposite sides even though their atomic weight is only off by 1. One is considered a metal, the other isn't. One is a non-reactive noble gas, the other can be explosive.
The valence numbers form a pattern because of the number of positions an electron can fit into in the outer shell of an atom. The pattern repeats because it was organized that way.
Very likely biology works the way it does because of reactions between elements works based on electron bods. Which is why certain elements are useful to us, but the opposite is also true. Fluoride is very bad for us: it displaces iodine. Mercury displaces Magnesium. Trouble is, we can't use fluoride, and we can't use mercury.
(Similarly, if you take Vitamin D by itself in large amounts, it becomes toxic, but if you take it with A, it doesn't.)
But just because elements are near each other doesn't mean much. We need zinc, but Cadmium is poison to us. We need Selenium, and Phosphorus, but their neighbor Arsenic is poison, etc.
Copper, Zinc, and Iron are needed. Nickel, though is toxic even though they're neighbors.
It's funny how people say that things are good or bad, or evil, or that plants or humans are designed for this or that - they're all just accidents of evolution and of nature.
No grain woke up one day and thought to itself, "You know, I should make some phytates to prevent those annoying birds from eating me. And maybe some proteins that can puncture holes in the small intestines of those pesky apes." No nightshade woke up and said to itself "If only I had some toxins in my skin, I think I'll make some solamine, that'll teach those gophers not to eat me!"
No mammal woke up one day and said to itself "You know, I wish these useless thumbs were opposable" and woke up the next day with opposable thumbs. No primate woke up one day and said "I wish I had a bigger brain and shorter guts and smaller jaw and discovered how to cook food, that way I wouldn't have to chew roughage all day long" and it was so. It all happened by accident, despite wishing.
Think of how many brave individuals must have lost their lives from not being afraid of fire or not feeling pain from intense heat, and perishing. Those that did fear fire and felt heat and felt pain survived. Despite this, a bunch figured out how to control it and cook with it, and thus, once the large guts and large jaws were unnecessary, evolution shrunk them out over many generations.
Problem is evolution takes a long time, which is why modern rodents are adapted to eating grains and modern humans aren't - rodent life spans are shorter than ours so they have one or two orders of magnitude more generations than us.
But us humans, we have yet another trick! We're also pattern recognition machines. We see patterns in everything. We see bunnies or elephants in the clouds, and heck, whole religions were probably based on whether or not a virgin that fell into a volcano prevented its eruption, or perhaps whether a specific dance would bring rain or not.
Biology shows certain elements have affinity with certain other elements because of their properties. Humans calling themselves, first alchemist, then chemist, organized these into easy to read tables based on those properties (valance and atomic weight).
It's not too big a coincidence that multiple elements work on the same pathways are neighbors on the table, but, some of those neighbors will be detrimental to us.
It is pretty cool to see groups as patterns, but the really beautiful answer is, we designed that table that way. So let's not say that the patterns that we ourselves organized, are an accident of nature.
on September 26, 2011
at 10:18 PM
Heck no Travis. I haven't looked at a periodic table for about 45 years. But I am glad people like you look things up, figure them out, and let me know because I still read!
on September 26, 2011
at 11:38 PM
1+ while I do my chemistry homework.
on September 27, 2011
at 01:26 AM
You make a very valid point about supplementation. You can cause deficiencies in one element by supplementing in another because of the common and competitive pathways various elements share.
I don't know however that your strategy for segregation supplementation is all that worthwhile. Sure, when it comes to absorption there may be some effects, but supplementing with excess Zn is going to alter your Cu and Fe levels, outside of their absorption profiles.