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Quest Diagnostics recent blood test show high Osmolality


senior member
Concord, NH
Value was 426, range is 278-305 mOsm/kg.

Read up on this a little, seems to suggest I am dehydrated. Or am consuming to much salt or have a kidney issue :( I don't think I urinate all that much, I do after I have had my coffee, probably about 3 to 4 cups when i get my day going. Seems to help the brainfog :) I don't use sugar for my coffee either, I use Stevia.

I do have no problem consuming salt, thought we were supposed to?!

High values
High levels may be caused by:

  • Too little water in the body (dehydration).
  • High levels of salt or sugar in the blood. This may be caused by problems such as poorly controlled diabetes.
  • Damage to the kidneys. This can cause a buildup of urea in the blood.
  • Poisoning with certain substances. These include ethanol (the alcohol in alcoholic drinks), rubbing alcohol (isopropanol), wood alcohol (methanol), and antifreeze (ethylene glycol).
  • A rare disease, such as diabetes insipidus, that causes the kidneys to lose water and produce large amounts of urine.




Senior Member
NSW Australia
High levels of sodium in the blood are a problem with the body's balancing between what is in the cells and what is in the blood. It has little to do with dietary sodium.
How much water do you drink? Along with the recommendation for those with low blood pressure/low blood volume to increase salt in our diet we need to increase fluid as well.


Senior Member
If you're like me and a whole host of other ME/CFS patients… you might have ADH deficiency. Without sufficient amounts of Anti-Diuretic Hormone in your system, you'll be perpetually dehydrated.

Dr. Paul Cheney and Dr. Ritchie Shoemaker have addressed the ADH conundrum in their research. Most ME/CFS patients don't have diabetes insipidus (I've been tested) but our symptoms closely resemble that. It's simply a lack of adequate ADH resulting from hypothalamic damage. There are things you can do to lessen the effects (Gookinaid or Hydralyte drinks) and a bunch of other things. But it's important to get your ADH tested to see if that's your issue.