Friday, April 11, 2014

Hair Mineral Analysis: Significant Correlations Between Calcium, Magnesium, Potassium & Sodium and Met. Syn., Insulin Resistance, Waist, BP etc. - Implications?

Does her hair hold the secret to her fitness body? Actually that's unlikely, but it appears possible that a hair analysis could reveals what's keeping you back from a similarly amazing physique.
Hair mineral analyses have been discredited by certain snake oil vendors who use them to sell their "oils" in form of an endless list of "essential" supplements you'd have to take if you don't want to end up as dead as the hair they used to produce the analysis. Still, they share one big strength with the more expensive RBC or other cell tests: They give you an idea of your actual calcium, magnesium, sodium and potassium balance.

Much in contrast to serum levels, by the way. If those are off, it's either due to an acute event (like diarrhea, for example ;-) or you have a real reason to be concerned. There is after all a really good reason these minerals are also called "electrolytes": They are heavily involved in the ion and thus charge-exchange that keeps your heart beating!
Serum analyses tell you if your heart will keep beating, but what do hair analysis tell you? That's a very valid question and the answer is NOTHING! You can use them to estimate your mineral balance, but a high calcium level in the hair, does not necessarily imply a high level in other body parts. Moreover, correlations as I am about to report them in today's SuppVersity article allow for hypotheses about causative effects, what they don't do, though is to prove cause and effect! Please keep that in mind while reading this article and before your next visit at your favorite quack.
Before we get to the actual hair mineral analysis data, let's briefly have a look at another set of striking and not so striking differences between the "normal" subjects and those with established metabolic syndrome:
Figure 1: Serum mineral concentrations, visceral (VAT) and subcutaneous body fat and smoking status in subjects w/ and w/out metabolic syndrome (Choi. 2014)
If you take a closer look at the data in Figure 1 you will see that - aside from marginal, but statistically non-significant differences in serum phosphor - the often-checked total Ca, Mg, K, Na & Ph concentrations did not differ between the two groups.
Potassium, insulin resistance & obesity: Later in this article you will learn that there was a negative association between the amount of potassium in the hair of the subjects and their HDL and insulin sensitivity. It's important not to confuse this with the message "potassium is bad for your insulin sensitivity" - in fact, in 1980, Rowe et al. observed significant decreases in plasma insulin response  to sustained hyperglycemia and a ~30% reduction in glucose metabolism (Rowe. 1980).
Moverover, visceral fat was a much more reliable parameter to distinguish the healthy and unhealthy subjects than subcutaneous fat and... a bit to my surprise: Smoking appears to be associated with a lower metabolic risk than non-smoking.

Let's take a look at the hair analysis, now

Much in contrast to the serum levels, the hair mineral analysis did reveal significant inter-group differences and corresponding correlations:
Of all potentially toxic molecules the researchers measured only the levels of arsenic and lead differed significantly between the two groups. The concentrations of cadmium, mercury, and aluminum were not different between the two groups, on the other hand, did not.
And what does that mean? If we take a parting look at the data in Table 1, you will see that, the one parameter that makes all the difference is none of the minerals. It's rather an old acquaintance: The total amount of visceral fat. With a p-value of p = 0.000 it's the best parameter we have to identify someone with metabolic syndrome. The hair minerals, on the other hand, may present with associations with individual features of the metabolic syndrome, namely...
Table 1: Multiple logistic regression analysis for hair mineral concentrations with metabolic syndrome (Choi. 2014)
  • low calcium, low magnesium ➮ high blood pressure, high blood sugar, triglycerides, weight and waist,
  • high sodium, high potassium ➮ low HDL,
  • high copper ➮ low blood pressure, low weight, low waist, high insulin sensitivity,
  • high chromium ➮ high weight, high waist, and
  • high cobalt ➮ low blood pressure
Now, since, we don't know how exactly the hair mineral content ant the nutritional intake are connected, it is very difficult to make any recommendations based on these observations.

What appears to be relatively certain, though, is that these new findings don't change anything about my previous recommendation to make sure that you get enough calcium and magnesium - the thing about potassium, on the other hand, strikes me as odd. As an antagonist to calcium, the negative effects of K may yet simply be a result of a Ca deficiency in the average mid-40s subjects in the study at hand.
References:
  • Choi, Whan-Seok, Se-Hong Kim, and Ju-Hye Chung. "Relationships of Hair Mineral Concentrations with Insulin Resistance in Metabolic Syndrome." Biological Trace Element Research (2014): 1-7.
  • Rowe, John W., et al. "Effect of experimental potassium deficiency on glucose and insulin metabolism." Metabolism 29.6 (1980): 498-502.