Labwork 101 Flashcards
- When a patient has low serum iron or hemoglobin, the most important lab marker to be checked regarding iron sufficiency is FERRITIN (a marker of the body’s iron stores). List three relatively common reasons as to why someone would have low serum iron.
● Insufficient dietary intake, also perhaps high intake of non-heme (vs. heme) iron.
● Maldigestion (examples of this are also acceptable e.g. low stomach acid, low digestive enzymes). Sufficient stomach acid is required to isolate iron chelates from their mother proteins. Digestive enzymes are also important in this function. Hypochlorhydria may be a significant cause of low iron (e.g. H Pylori infection, ongoing use of PPI or similar medications to purposefully reduce stomach acid, chronic stress, low thyroid and/or adrenal function).
● Malabsorption. Damage to the intestinal lining (e.g. parasite infection, yeast overgrowth, SIBO – especially due to the biofilms created by these microbes) can impair nutrient absorption (even if there is adequate digestion). This may also be due to frequent/chronic diarrhea or other causes of fast transit time (poor eating hygiene, anxiety, lactose intolerance, fructose intolerance).
● Iron can be poorly absorbed in some individuals when consumed with substantial amounts of calcium (especially calcium supplements).
● Dietary oxalates and phytates and tannins (e.g. coffee or tea intake) can also bind with iron and impair absorption (by increasing stool excretion).
● High levels of hepcidin. Such as from taking too frequent doses of iron supplements.
● Recent blood loss e.g. heavy menstrual period without sufficient ferritin, accident involving substantial bleeding, blood donation (voluntary or medical). This is an excellent example of the importance of asking your client key questions in regard to unusual labwork results.
● ‘Anemia of chronic disease’ or Infection (e.g. parasites, fungal, bacterial). Ferritin will often rise with strong, ongoing inflammation (hence our knowledge of ferritin as an inflammatory marker) as the body binds up iron to prevent it from contributing to an infection (e.g. common cold, flu, urinary tract infection, other viruses, H Pylori, intestinal Candida). In these cases, serum iron and hemoglobin will likely both be low-normal while ferritin will rise significantly; TIBC (total iron-binding capacity) will also usually be relatively low in reference range, a reflection that there is no lack of iron.
● Internal bleeding. There are actually many more serious and less common reasons that might cause low serum iron, but the above items will be much more common in our clients and patients.
● Lead toxicity.
● Poor iron retention or transport due to nutrient imbalances e.g. low Vitamin B6, low
Vitamin A, high or low copper, high manganese, high zinc.
- Labwork reference ranges are not optimal ranges but rather they represent
STATISTICAL NORMS (or mathematical normal ranges). They typically capture what 95% of the control population actually has. Especially in a society where chronic disease is common, we remember that normal lab values do not represent health or absence of notable dis-ease.
- Generally, the best lab markers for ongoing sufficiency of minerals (e.g. zinc, copper, selenium) are :
cellular markers or levels.
In more conventional labs, these are typically levels of a mineral found in red blood cells and are measured via “RBC” markers. They can also be measured in white blood cells (e.g. Spectracell Micronutrient test). In some cases, there are excellent related markers such as ceruloplasmin for copper, as ceruloplasmin is the primary binding protein for storage of copper in the blood. Another excellent example is ferritin, as the bound storage form of iron. There may also be related functional markers such as alkaline phosphatase often being clinically low (or suboptimal in the bottom 15% of a typical normal reference range) in a person who needs more zinc or magnesium.
- Various organic acids can be measured in urine as “functional markers” of nutrient sufficiency
in a unique human body. The most common organic acid measurement for Vitamin B12 is
methylmalonic acid (MMA) or methylmalonate. MMA can be measured in either URINE or BLOOD.
- Your client, Fred, brings you his prior labwork and you observe a fasting glucose level of 91 mg/dl two years ago, 93 mg/dl one year ago, and 95 mg/dl from Fred’s latest labwork last month. It is a reasonable assumption that a root cause of Fred’s labwork is likely to be?
INSULINE RESISTANCE
A few other related notes to keep in mind for this case profile…. Suboptimal magnesium is often involved in entrenched insulin resistance, so consider recommending that Fred pursue that labwork. Ongoing oxidative stress is also often involved in insulin resistance; labwork such as elevated urinary 8-OHdG (8-hydroxy-2’-deoxyguanosine) or within range elevated GGT (gamma glutamyl transferase) can help to assess overall oxidative stress load and the need for more concentrated antioxidant support. Remember too that a persistent state of high stress hormones (e.g. cortisol) can elevate blood sugar completely separate from diet, so this may be an exacerbating factor for Fred (or in more rare cases, the primary factor vs. insulin resistance).
- What is your reaction to a TSH (thyroid stimulating hormone) level of 4.8 U/ml? Typical reference range is 0.5 to 5.5 U/ml. Comment on both the marker and the level. Be thorough.
A thyroid stimulating hormone or TSH level of 4.8 U/ml IS MOST LIKELY – BUT NOT NECESSARILY – SUBOPTIMAL. It’s a hormone, and unique, individual normal levels can vary dramatically. As is true with all lab markers, some individuals simply and naturally run high or low within a normal range. Your next step is a careful investigation of your patient’s symptoms.
If they are presenting with hypothyroid symptoms (e.g. tendency to feel cold all over (esp. when If they are presenting with hypothyroid symptoms (e.g. tendency to feel cold all over (esp. when others don’t), hair loss from head, constipation, elevated LDL cholesterol, feeling of sluggish energy, steady weight gain without other explanation, IBS or similar indigestion, brain fog, insulin
resistance), then a FURTHER INVESTIGATION OF THYROID HORMONES is a prudent recommendation e.g. a full thyroid panel such as TSH (again, to confirm results), Free T4, Free T3, both TPO and Tg
thyroid autoantibodies, and – ideally – Reverse T3 as well.
Overall, you should have also commented on at least a few of the following regarding this TSH value: (1) evidence that the brain is trying to get the thyroid to work harder (e.g. feedback system, brain unsatisfied). (2) Reference ranges are not optimal ranges; 4.8 U/ml most likely suboptimal. (3) More data needed e.g. full panel thyroid to assess imbalance. (4) Need to consider symptoms/history and not just lab data. (5) Brain can be satisfied re: thyroid hormone before other body parts e.g. liver. (6) Even if the TSH was lower or more “optimal”, a full thyroid panel is still necessary to understand if there is underlying imbalance in the thyroid hormones themselves. (7) There may be an autoimmune dynamic at play (or one could assess autoimmune thyroid antibodies to see if this is the case).
- What is your reaction to an RBC magnesium level of 4.2? Typical reference range is 4-6 mg/dl.
Comment on both the marker and the level. Be thorough. Your answer should include several of the following:
● Deficiency/insufficiency of magnesium is common.
● This value is typically suboptimal against this reference range (lowest quartile).
● Bio-individuality may change the level a unique individual needs (and thus symptoms review is key).
● RBC mineral lab marker is a good way to assess sufficiency vs. serum/plasma which are highly affected by recent dietary intake (which, if abnormal, can skew interpretation value notably).
● Medications may be depleting (e.g. diuretic, proton pump inhibitor).
● Low stomach acid may be contributing to depletion via maldigestion.
● Magnesium supplementation must be done with great care (or may be contraindicated)
in individuals with kidney disease (only if applicable).
● Magnesium acts as “master” electrolyte and ensures sufficient cellular uptake of potassium.
● Levels are commonly low in those with insulin resistance and/or hypertension.
● The most appropriate form of magnesium supplementation depends on the individual’s needs to ensure there is relief of key symptoms (examples may be given).
● Wasting may be due to high intake of alcohol, soda, black tea, or coffee.
● Increased demand due to high intensity exercise or aggressive weight-lifting/lactic acid production.
- Serum calcium levels primarily reflect the health of the ___?
the PARATHYROID GLAND. (In case you were thinking about pH….Yes, calcium is also a secondary alkaline buffering agent in the blood, but the primary agent that keeps the pH of our blood in a very tight zone is bicarbonate.)
Calcium is the only mineral element in the body that has its own regulatory system. Optimal serum calcium varies by age (and typically labs do not unfortunately adjust reference ranges to account for
age) and also recent intake. For adults in their 40s and older, optimal serum calcium is in the 9s
(typical reference range 8.6 to 10.4 mg/dl). Serum calcium in older adults that is consistently in the
10s or consistently jumps back and forth between the 10s and then lower in the range (without supplemental calcium intake) is likely indicative of a parathyroid issue, especially if parathyroid hormone (PTH) is elevated while serum calcium is also elevated. PTH is easily checked via blood level.
- The optimal place for your labwork results to be within a typical normal reference range is
HIGHLY VARIABLE Or “it depends”!
We discussed this key concept at length within the course. Optimal lab values depend on such factors as:
● The lab marker itself (much better to be higher in a desired marker e.g. RBC
magnesium and lower in an undesired one C-reactive protein (CRP))
● The person’s demographics (e.g. age, sex, such as progesterone levels in a late perimenopausal woman vs. one at the height of her menstruating and fertile years)
● Recent life experience (e.g. someone just getting over a short cold is likely going to have high total WBC count or someone who is in the process of reversing their type 2 diabetes may consider a HbA1c of 6.0% to be a major victory when it was 7.0% previously).
- What is LDL cholesterol? Why is it the only important lab marker included in a typical, conventional lipid panel?
This is a bit of a trick question on multiple fronts. LDL is low-density lipoprotein, actually a carrier of cholesterol in the body (LDL is not cholesterol itself at all but rather a way of estimating the amount of cholesterol in the body).
LDL is not at all the only important lab markers in a typical, conventional lipid panel. LDL typically only becomes dangerous for cardiovascular health when arteries are inflamed (from e.g. diabetes, simmering infections, toxicity) and attract an immune response from the body.
LDL represents all of the cholesterol that is being transported from the liver to the rest of the body to serve all critical functions (e.g. building cell membranes, regenerating tissue, generating all steroid hormones). The total amount of LDL (e.g. 212 mg/dl) does not correlate well with the incidence of cardiovascular disease. One needs a Cardio IQ or other more detailed lipid profile to understand the total number of LDL particles, their type, and size. Among conventional lab markers, both HDL and triglycerides are extremely important markers, especially in a ratio (where optimal trigs/HDL is
2.0 or less). Triglycerides are the true free fats in the blood, and HDL has the role of retrieving damaged LDL and returning it to the liver (though it can become dysfunctional as well when excessively elevated in an environment of high oxidative stress).
