Nov 27

Lab Testing Guide 2.0

An Update

A little over a year ago, Craig wrote a post on what lab tests to get to measure your metabolic health. Although the original post still has great information, including how to request tests from your doctor, we figured it was about time to make an update, in order to provide information on which tests we think still remain relevant, which tests are worth testing frequently, new tests we’ve come across in the past year (or tests that have gained more relevancy over the past year), as well as make it a bit easier to pick tests based on specific needs (e.g. budget, level of data desired, etc). Hopefully this post will help with that, and make picking out tests, and tracking your health, a bit easier.

The Tests

The tests are divided into “sets”, organized by what how much data you’re trying to gather, as well as by cost for those paying out of pocket (cost will vary by which provider you order through, but the tests which provide important information for the least amount of cost are in the first sets, while more niche tests are in the last sets). You can also click on the test names to get a brief description, and possible confounders for the results if we know of any.

The “Basics” Set

These tests are good to get every single time. This list is for those of you who are just looking for the bare basics and aren’t too interested in the more niche markers, or you’re paying out of pocket and you’re on a budget.

CBC With Differential/Platelet

This is actually a pack of over a dozen different measures, which can help verify or hint at issues like anemia, or infection, among others. If self experimenting this can be helpful to verify possible illness wasn’t a confounder for your results.


Comprehensive Metabolic Panel (14)

This is another pack, but this one focuses on electrolytes (e.g. sodium, and potassium levels in the blood), liver enzymes (ALT, AST), and some measures of kidney function. Some of these can be impacted by simple issues (high BUN from dehydration, high ALT/AST from exercise prior to the test) so try to make sure you keep those in mind when getting the test done to make sure you don’t accidentally influence the results.



High Sensitivity C-Reactive Protein. hs-CRP is a measure of inflammation – however it’s worth noting that it tends to react pretty strongly to even small sources. Recent injury, intensive exercise prior to the test, infection, or issues related to diet or environment. Regardless, it’s worth it as a “look closer” marker, and can help suss out issues that weren’t noticed before.

Dave also has an article going over his experiences with testing hs-CRP which can be read here.



Short for Hemoglobin A1c. A measure of glycated hemoglobin (hemoglobin is a protein found in red blood cells), generally used for diagnosing pre-diabetes or diabetes. Good to keep an eye on!



Far before blood glucose dysregulation appears, some research suggests that hyperinsulinemia can be the canary in the coal mine for many health issues and can be a risk factor for issues ranging from diabetes to PCOS to psoriasis. Far beyond its use in energy metabolism, insulin can also have an effect on immune cells, and more as described in this post.


Lipid Panel

A collection of (generally) four tests, including Total Cholesterol, HDL-C, LDL-C, and triglycerides. You can also calculate remnant cholesterol from your lipid panel, as well as using it to determine if you are a so-called Lean Mass Hyper-responder. Common things people look for are high triglycerides, and low HDL. A note should be made that – triglcerides in particular – are very dynamic and so a normal fluctuation of roughly 20-30% for triglycerides is not unusual. HDL tends to be relatively more stable, although it can be affected by dietary fat intake, sudden drops in HDL-C (especially with no change in diet) are unusual.

“Digging A Little Deeper” Set

Perhaps you’re just interested in markers beyond the basics, you’re trying to pinpoint a problem, or you’re just looking to get a broader look at the bigger picture – this is the list for you! Combine this with the “basics” list.



Ferritin, Serum

Ferritin is a protein involved in iron storage, and testing it can help determine if one has anemia (if paired with other results), but it is also an acute phase reactant and can be paired with hs-CRP in order to help spot ongoing or acute inflammation.



GGT stands for Gamma-Glutamyl Transferase and is a type of enzyme found in multiple types of tissues, but is mostly found in the liver. It can be used to help detect possible liver damage, or other issues.


Uric Acid, Serum

Those with metabolic syndrome tend to have higher levels of uric acid in the blood, thus it can be used as an additional marker of metabolic health – high levels can also lead to gout (a type of arthritis affecting the joints). However, there appears to be a transient rise in uric acid during the adaption phase of a ketogenic diet, so any testing in that time period may be inaccurate in regards to this marker. Higher levels should resolve once adaption is complete.


Insulin and C-Peptide, Serum (instead of insulin from the basics set)

Includes an insulin test, as well as C-Peptide. C-Peptide is released when insulin is produced, and thus is another measure of insulin production in the body. It can be slightly more reliable of an indicator of insulin secretion, however, as it has a slightly longer residence time in the blood than insulin does.


NMR Lipoprofile

This provides a bit more information than a standard lipid panel. Along with Total Cholesterol, HDL-C, LDL-C, and triglycerides, it also includes information like LDL-P (also referred to as “particle number”), small LDL, and HDL-P.



Lipoprotein(a) has been getting more publicity lately, and is generally considered a lesser known cardiovascular risk marker. Levels are generally considered to be mostly genetic, however recent experiments have demonstrated this may not necessarily be true – and high values could be the result of genetic factors, dietary factors, as well as inflammatory signalling. A more in-depth review on lipoprotein(a) can be found here.


Lp-Pla2 Activity

A cardiovascular risk marker, and possible marker of oxidative stress, occasionally factored in when looking at lipoprotein(a) levels. Anecdotally it seems low carbers have slightly higher levels, but well below thresholds mentioned in studies using it as a marker of cardiovascular disease risk alongside lipoprotein(a)

“Citizen Scientist / Establishing Extensive Baseline” Set

Planning to do some heavy duty experimenting of your own, or planning to replicate one that’s already been done? About to make a major lifestyle change, and want to capture an extensive baseline? Got a Christmas bonus, and the thought of plentiful data tickles your fancy? This is the list for you! Combine with previous two lists.



Homocyst(e)ine, Plasma

Higher levels are possibly associated with a higher risk of stroke, heart disease, and other health ills. Higher levels could be due to deficiencies in B vitamins (like B12 or folate), which could be due to inadequate intake or issues properly absorbing the vitamins, such as those with mutations in the MTHFR gene, although there are other possible causes as well. More context can be provided by also testing B12 and folate levels.


Fatty Acids, Free (Nonester)

A measure of free fatty acids (e.g. fat-based energy) in the blood – another way to tune in to energy metabolism.


Vitamin B12 and Folate

Vitamins used for processes like mood regulation, creation of healthy red blood cells, etc. Deficiencies can lead to anemia, birth defects, and other issues.



Tumor Necrosis Factor Alpha. A pro-inflammatory cytokine (e.g. a protein used to signal inflammation). Another inflammatory marker.



Insulin-Like Growth Factor-1; a growth hormone. Chronically high levels (along with hyperinsulinemia) are associated with increased risk of cancer, as discussed here. Levels may also change during multi-day fasting, exercise, etc.


“Thyroid Check-in” Set

Want to check in on your thyroid health? Is your doctor not sure what to test for, or only tested TSH without looking further? Here are some other tests you can order, or suggest, that may provide more useful and in-depth information about how everything is working. Combine with any other list(s).



A thyroid hormone, which helps control metabolism. Low levels could be indicative of a condition called hypothyroid (marked by fatigue, cold extremities, sensitivity to cold, and others), but it’s also worth noting that those following a low carb, ketogenic, or carnivorous diet may have lower levels of T3 and yet be asymptomatic. This has been argued to be an adaptive mechanism, and may not necessarily be hypothyroid in-and-of-itself. 


Reverse T3, Serum

Reverse T3 is essentially an inactive mirror version of T3. It competes for the same receptors, and thus inhibits T3 function. In other words, it helps to keep T3 in balance – where too much T3 can result in symptoms of hypothyroid while too little can result in symptoms of hyperthyroid (even if TSH and T4 are normal). It can help get a better over all picture of thyroid health, and the context of the other numbers.


Thyroxine (T4)

Thyroxine (or T4) is another thyroid hormone, and is also used to regulate metabolism. Low or high levels can be indications of hypo- or hyperthyroidism as is true of T3.

Combined with T3 uptake, a free T4 index can be provided, which is used to evaluate thyroid function.



Thyroid Stimulating Hormone – it’s actually a hormone made by the pituitary gland, which stimulates the thyroid to produce thyroid hormones. Often this is ordered alone, but comes with the downside of the lack of context given by the other measures on the list. One can have normal TSH, but still be hypo- or hyperthyroid, thus the importance of verifying the other measures as well.

“Overachiever” Set

The most generally expensive or unwieldy tests belong here. Only for the most overachieving testers with money to burn, and questions to answer.



The counter to insulin. While insulin is generally used to signal building and storage, glucagon generally does the opposite. In Ben Bikman’s presentation from Low Carb Breckenridge 2018, he argued that insulin response should be taken into context alongside glucagon’s response as well (such as the insulin response to dietary protein intake).



Another pro-inflammatory cytokine – can be combined with others for redundancy and validation of higher levels of inflammation. This is on the overachiever set, because it’s generally more expensive than other options.

Where to Get Them

Working with your doctor is one option for ordering tests

Depending on how open your doctor is to getting additional testing done, you could always work with them to order some of the tests, especially if it’s the items from the “Basics” set. However, the chance of them ordering high frequency tests (for experiments, etc), or some of the more obscure tests like IGF-1, is less likely. Dave and I are currently beta testing a way to get inexpensive labs available for those in the states, but in the mean time most people I’ve seen choose to go through third parties to order the tests, such as Request a Test and Ulta Lab Tests. These write up a lab order which you get fulfilled through a private lab, such as Quest or Labcorp. (This will obviously differ by country, however, so if anyone knows of different providers in other countries, feel free to leave them in the comments if you know they’re reliable.)


Nov 21

#CholesterolScience Doubleheader Next Week – Ivor Cummins Wednesday – Joel Kahn Friday

This coming week I’ll have two interviews, Ivor Cummins on Wednesday and Joel Kahn on Friday. (Bios below)

How to Ask Your Question

You can ask questions of either Ivor Cummins or Joel Kahn in advance of the broadcast one of two ways:

  1. Comment to this blog post down below — but keep it short! (Don’t ask multiple questions)
  2. Comment on Twitter using the hastag: #CholesterolScience

Feel free to direct your question to the guest you want to answer. If you don’t, we’ll choose for you.

As always, keep it respectful and fun.

Ivor Cummins

(Taken from his bio for the upcoming Low Carb Denver conference)

Ivor Cummins completed a Chemical Engineering degree at UCD in 1990. He has since spent over 25 years in corporate technical leadership and management positions and was shortlisted in 2015 as one of the top 6 of 500 applicants for “Irish Chartered Engineer of the Year”. Ivor’s focus and specialty is leading teams in complex problem-solving scenarios. He has often led worldwide teams with over 60-70 engineers working on major technical issues; the largest of these involved product issues where hundreds of millions of dollars were in the balance.

Several years ago, Ivor encountered a complex technical challenge in his personal life. Receiving poor blood test results, he was unable to get solutions via the doctors consulted. He thus embarked on an intense period of biochemical research into the science of human metabolism. Within eight weeks he had resolved and optimized all of his blood test metrics. Also, he had shed over 15Kg of bodyfat with relative ease. In the following years he continued his research on the many “root causes” of modern disease, from “cholesterol” through to insulin resistance.

He has become a professional speaker of note, giving many public lectures and chairing interviews with worldwide health experts. Most notably he was invited by the President of the British Association for Cardiovascular Prevention and Rehabilitation (BACPR) to give a keynote talk on heart disease root causes, at their annual conference in London last October. All of Ivor’s public lectures and interviews are available on his YouTube channel, where nearly a million views have been recorded to date:

Dr. Joel Kahn

(Taken from the About section at Dr. Kahn’s website)

At his core, Dr. Joel Kahn believes that plant-based nutrition is the most powerful source of preventative medicine on the planet. Having practiced traditional cardiology since 1983, it was only after his own commitment to a plant based vegan diet that he truly began to delve into the realm of non-traditional diagnostic tools, prevention tactics and nutrition-based recovery protocols. These ideologies led him to change his approach and focus on being a holistic cardiologist. He passionately lectures throughout the country about the health benefits of a plant-based anti-aging diet inspiring a new generation of thought leaders to think scientifically and critically about the body’s ability to heal itself through proper nutrition.

One of the world’s top cardiologists, Dr. Joel Kahn has treated thousands of acute heart attacks during his career. He’d like all that to stop. He’d like to prevent ALL future heart attacks by breaking through to the public to educate and inspire a new holistic lifestyle. Now is the time to focus on educating the public to eat clean, sweat clean and apply cutting edge science to their lifestyle.

Nov 21

#CholesterolScience Show – with Dr. Spencer Nadolsky

Show Notes:

0:25 Greetings

1:36 Spencer’s background

3:35 The big seven questions intro and context into Spencer and Dave’s background together

4:52 Question Number One: What is your current opinion on the optimal range of Total Cholesterol?

5:24 Question Number Two: What is your current opinion on the optimal range of LDL Cholesterol?

5:55 Question Number Three: What is your current opinion on the optimal range of HDL Cholesterol?

6:43 Question Number Four: What is your current opinion on the optimal range of Triglycerides?

7:00 Question Number Five: In regards to cholesterol lowering medication, do you think too little or too much is being prescribed?

7:33 Question Number Six: If you had to guess a percentage, how much of modern heart disease is a result of diet?

8:10 Question Number Seven: Do you feel those on a low carb diet should take steps to lower LDL-C if it has increased, if all other cardiovascular risk factors have improved?

9:20 How Spencer’s opinion on cholesterol has developed, and how it has changed over the years

12:42 How Spencer sees LDL’s role in atherosclerosis

14:20 Coming from a position of skepticism towards the LDL hypothesis and why Spencer’s views changed

15:45 Study mentioned: ENHANCE trial

16:35 Study mentioned: IMPROVE-IT trial

16:50 Note: Genomic Wide Association studies refers to studies which look at genetic causes of something (e.g. high or low cholesterol) and associate it with occurrence of cardiovascular disease or other issues.

18:05 Do you feel there are positive things about having higher LDL cholesterol or higher LDL particle count?

21:30 Looking at All-Cause Mortality in people with hypobetalipoproteinemia or abetalipoproteinemia

Note: Hypobetalipoproteinemia is a condition resulting in unusually low levels of apoB containing lipoproteins (VLDL, LDL, chylomicrons, etc), abetalipoproteinemia is a similar condition resulting in near absent levels of apoB containing lipoproteins.

23:40: Social Media Questions intro

23:55 What is “Best practice” for evaluating desirability of statin therapy and weighing likely benefit versus potential adverse side effect?

26:00 The importance of having honest dialogue with your doctor (and others)

28:00 Is the focus in the right place for areas of interest and understanding for doctors (diet, and medicine)?

30:48 What is the current verdict on triglyceride to HDL ratios, and how do you correct a high ratio?

32:40 Question intro: Please include the ramifications of apoe4 in these discussions

33:00 Discussion on lean mass hyper-responders

35:40 Hyper-responders in Spencer’s clinic, and in Dave’s experience, and apoe4

38:00 Dysbetalipoproteinemia and apoe2/2 isoform

Note: Dysbetalipoproteinemia is a genetic disorder marked by increased levels of remnant lipoproteins due to impaired clearance.

39:00 Dave’s white bread and processed meat experiment and impact of energy metabolism on lipids

39:40 For hyper-responders, why does switching saturated fat for other fats lower LDL-P and is this beneficial?

42:15 What explains the rise in CVD in the industrial/developing nations and why do undeveloped people not have cardiovascular disease?

44:25 What is the importance of very high LDL-P in light of having pattern A in regard to cardiovascular disease?

Note: Pattern A is referring to having a majority of LDL particles that are a larger size, compared to having a predominance of “small dense” particles, classified as Pattern B. Pattern B is considered to impart higher risk of cardiovascular disease.

46:40 Genetically high levels of LDL versus dietary causes, are they the same? Will Lean Mass Hyper-responders develop issues like xanthomas?

51:50 How important/significant is RBC [red blood cell] cholesterol pool to our health, and how is it impacted by changes in the lipoprotein cholesterol pool?

53:15 Blog questions intro

53:35 What is the role of cholesterol on lipoproteins, if the energy model is correct?

55:00 Dave’s resistance training experiment

58:45 What does Spencer think about the study regarding all-cause mortality being inversely related to total cholesterol in women?

59:40 PCSK9 inhibitors, what to make of the data?

1:02:04 Quality of life consideration

1:04:10 Questions from the chat

1:04:35 How do they measure cholesterol if it’s water insoluble?

1:06:40 What does Spencer think about CAC scores?

Note: A Coronary Artery Calcium score is a CT scan that looks for calcified plaque in the arteries. The scores range from 0 to >1000 with 0 being very low risk, and >1000 being extremely high risk (of cardiovascular disease risk, as well as all-cause mortality).

1:10:20 Spencer’s blog post for Cholesterol Code

1:12:20 Where to Find Spencer Nadolsky

Twitter: @DrNadolsky

Instagram: @DrNadolsky

Facebook: Dr. Spencer Nadolsky

Nov 15

Submit your questions for Dr. Spencer Nadolsky on our first #CholesterolScience Show

Dr. Spencer Nadolsky – Board certified family and obesity physician taking his lipid boards this spring. Former division 1 NCAA heavy weight wrestler.

New Series

Next week Tuesday (November 20th), I’ll be interviewing Dr. Spencer Nadolsky on the first #CholesterolScience series. This show is meant to incorporate many different viewpoints on cholesterol and lipids. (See his page here:

As many of you know, I’m a bit more cautiously optimistic with regard to higher LDL cholesterol and particle count where I believe there is insulin sensitivity and metabolic health, often reflected in low fasting insulin, low triglycerides, and high HDL.

This is why I’m extremely excited to have Spencer as our first guest as he will be giving a different opinion — you could say, a cautiously pessimistic point of view. In fact, he’s currently working on an article to be published right here on CC in the coming future on this very topic.

I’d particularly like to laud Spencer for being the most curious of those outside the low carb community with regard to the lipid energy model, prominent studies cited in favor of cholesterol, and the general opinion of low carbers in general to best construct a rebuttal. If you all know me well by now, you know how seriously I take moving this conversation forward and truly welcome serious discussion and constructive feedback.

General Format

This will not be a formal debate with Spencer and myself. Rather, I’ll be collecting questions here and on social media that we’ll curate and let him know about in advance. I want this to be generally relaxed and productive. I want any/all who have great information to share, whatever their viewpoint, to feel they can come on the show and express their ideas and research.

With this in mind, I want to ask everyone to be sure they are especially respectful of differing opinions on this show. Please don’t personalize. Feel free to attack their ideas (constructively), not the people themselves.

Rebuttal Rule

Naturally, if this series gets legs, more and more guests may remark on prior guest appearances. As with a more formal debate, if one guest references a previous one specifically and their position, I’ll do my best to allow the targeted guest to have a rebuttal response in a separate video, blog post, etc.

How to Ask Your Question

You can ask questions of Dr. Spencer Nadolsky in advance of the broadcast one of two ways:

  1. Comment to this blog post down below
  2. Comment on twitter using the hastag: #CholesterolScience

Again, keep it respectful and fun.


Nov 09

The Tandem Drop Experiment – Part 2 – Carbs

A Very Different Path

If you haven’t already, be sure to first read Part 1 of this experiment by Siobhan Huggins.

Originally, Siobhan and I were going to simply do the same protocol at the same time, perhaps something similar to the one I did with my sister two years ago. But it occurred to me that it might be much more interesting if we tested both directions in lowering LDL that would lend further evidence to the Lipid Energy Model.

I began exploring the idea of going carb-centric in order to showcase this shift in energy metabolism having a likewise effect on my cholesterol. But while I’m at it, why not go big? Why not choose foods that would achieve the task yet from a category no one would associate with “healthy” or “whole food”? I settled on white bread and processed meat.

And heck, while I’m at it, I should exceed my prior levels of carb intake to drop below my previous fasting record LDL of 103 mg/dL, courtesy of the Capstone Experiment. In fact, I predicted this outcome and shot a video in advance of the experiment.

Whereas Siobhan was invoking the Inversion Pattern on her end of the experiment, I was straight up changing my metabolic pathway. As mentioned in the video above, I was moving from a fat-based metabolism to a glucose-based metabolism.

The Macros

I had originally wanted to hold out on the “Peak Levels” until I saw that plateau I mention in the video above. But honestly, the massive levels of glucose throughout this experiment being indicated by my Continuous Glucose Monitor (CGM) was making me very uncomfortable. Thus, once below 100, I found myself ramping down soon (starting at 9/25).

For some perspective, here’s my CGM before this experiment (while keto):

Very steady, well controlled glucose levels

You see that slight rise about 2/3rds of the way in? That’s when my glucose was just 105 mg/dL. Yes, that’s how steady this graph is when I’m fully keto — you can’t even tell when I’ve eaten.


Highly variable glucose levels with very high peaks throughout

You see that vertical line on the left side? That’s marking that peak at 183 mg/dL (shown in upper left). In other words, I’m clearly riding massive waves of high glucose throughout this experiment. While I expected this going in, it sure doesn’t help the ol’ psyche to see it in real time… although it does make for some good data.

The CardioChek Data

Let’s combine all three cholesterol markers into a single graph:

During the Ramp Up period where my carbs were slowly being increased, we don’t see a big drop in LDL, nor an increase in triglycerides (TG). Yet once entering into the Peak Levels portion, this changes and we observe LDL dropping dramatically while TG rises in kind.

The Lab Data

I took a total of three lab draws. One on the 17th right before the ramp up, one on the 24th which was midway in, and one on the 28th at the very end of the experiment. Ideally, I’d have had even one more at the end of the Peak Levels period, but I just didn’t know for certain when that would be and if I could get into the lab in time.

I actually got quite a bit of data, but I’m going to highlight the most notable ones here:

Certainly the two that most stood out to me were the Ferritin and Glucagon.

The Ferritin dropping to 11 seems like a legit lab error. For context, note that I’m quite experienced with Ferritin as it is the one marker I’ve most worried about. Before Keto it was in the 500s and remained as such into the diet. However, in recent times it was in the 200s (as shown above). I’ve never seen it below 200, much less lower than 20. Thus, lab error is my my top suspect. (But hey, if it wasn’t, that would be quite a find!)

I blame Ben Bikman for the money I’ve been putting out to test Glucagon <shaking fist>. That said, I think I may be getting the value of Glucagon a lot more this time around. Rather than share my own thoughts on this (for now), I’ll let commenters pontificate down below as to why my fasting Glucagon did go down correspondingly with the rise of fasting insulin and why that last score of 80 pg/mL was actually the highest number I’ve gotten to date.

Brain Change

Of all the experiments I’ve done to date, this one was the most mood-altering, hands down. While I’d like to think I’m usually optimistic, fun-loving, and easy-going in most situations, instead I was much more irritable, temperamental, and chronically anxious. I just flat out complained several fold more, even though a lot of it was repetitive. Even more frustrating was that I was self aware of it but couldn’t seem to help myself.

I actually have several anecdotes from that period that are a bit embarrassing to reflect on. But surely the worst was my wanting to post a complaint I had with a company on Twitter. I didn’t ultimately do this, but it’s quite weird that I ever even considered it in the first place. It’s so not me.

I should emphasize that I don’t think this was strictly a carb thing by any means. I’ve done other carb-based experiments that brought me some issues but didn’t always alter my mood appreciably. I don’t think even the most avid high carb low fat advocate would push for an all white bread and lean meat diet.

Yes, while I mainly focus on cholesterol and lipids, I’ve become very aware that certain combinations of diet in these experiments will have profound impacts on my mood in many ways: temperament, irritability, contentment, and even the axis of outlook on life.

(Not So) Final Thoughts

There’s actually a lot more to unpack with this experiment than I’ve laid out here. The key goal was achieved in making for a record change in my LDL cholesterol over seven days. It came at a cost, of course, and I’d never settle for the resulting HDL and triglyceride levels I was observing during the experiment.


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