Ketosis for Cancer: Week 5—Ketogenic Diet Blood Tests

week 5: ketogenic blood tests

Note: this post was originally published on Aug 1, 2013. It was edited to streamline content and improve graphics in June 2016; therefore some older comments may pertain to content that was removed during revision.

This post is part of a series describing my attempt to follow Dr. Seyfried's dietary recommendations for cancer. To start at the beginning, please go to the first post: "Seyfried’s Ketogenic Cancer Diet: My Fasting Jump-Start to Ketosis."

Hindenburg disaster

My deep ketosis experiment went down in flames this week, but not before I had my blood drawn. I share my ketogenic diet blood tests with you as compared to results from a year ago. So, even though hunger eventually got the best of me, I learned a lot in the process, and hope you did too! Links to my moderate ketosis experiment are provided if you'd like to see what a more successful approach looks like.

Oh the humanity . . .

It was the best of times, it was the worst of times . . .

Call me Ishmael . . .

Oh, wait, that last one is completely irrelevant . . .

Before I begin my sorry tale, let me reassure you that I'm feeling much better now. And I have some very interesting lab test results to report. But the previous Thursday was a terrible, horrible, no good, very bad day. It started off with my posting about my unhappy fourth week on my modified version of Dr. Seyfried's ketogenic diet. Here's my data from that Thursday morning:

Day 29 (2/28/13)

Day 29 nutrition journal entry

(Food not included because I didn't keep track.)

So off I went to my primary care center, in my fasting state, with my blood sugar at 81 and my ketones at 5.2 (too high to be comfortable), hoping to be back home within an hour or so to eat breakfast and get ready for work. After having my blood drawn, I discovered that my doctor had not been willing to order all of the tests I requested, so I wrote myself a second set of orders and headed off to a different lab, on the other side of town, to have a second set of labs drawn.

Unfortunately, there was a wait of about an hour at the second lab. I had never been so hungry in my whole life. I would have eaten any one of you in a heartbeat, had you been willing to be grilled. Anyway, I got my blood drawn, but no time to go back home to eat—I had to go straight to the office—where there was no food . . . and I had a full day of patients ahead of me.

The only thing I had time to do was stop in the hospital gift shop on my way out and hope that something they sold was not made of carbohydrate. After a month of working so hard on this diet I really didn't want to lose whatever keto-adaptation status I may have gained by eating carbs. All I could find was mozzarella sticks, which don't agree with me, but any port in a storm . . .

By the end of the day I was still very hungry, so I ate chicken without counting protein grams until I felt better.

Danger: Cliff edge

Day 30 (3/1/13)

Day 30 keto diet journal entry

Notes: Still feeling off, despite eating as much as I wanted yesterday. So today I decided to continue eating as much as I want until I feel normal again.

At some point succumbed to a scoop of Ben and Jerry's sugar-free ice cream, which ultimately triggered carbohydrate cravings. And so it was that my human ketosis experiment went down in flames like a lumbering inflatable airbus . . .

So, I wondered—how can I use this failure to educate myself—and those of you who were hoping to learn something from my experiment? You'll notice that some values along the way are missing. This is because I was initially ambivalent at first about how to proceed, but by the end of the week I had settled on a way forward.

Day 31 (3/2/13)

Day 31 keto diet journal entry - potassium and magnesium supplements

Notes: I was concerned about my lingering lightheadedness/dizziness and low energy, despite eating plenty of food for three days in a row, including carbs, that I wrote to Dr. Rosedale through his website for advice. We don't know each other, so I was pleasantly surprised and very grateful when he wrote me back. One of the things he advised me to do was to begin taking potassium and magnesium supplements, so I started taking them this evening.

Day 32 (3/3/13)

Day 32 keto diet journal entry - with coffee

Notes: I woke up lightheaded, with low energy. I decided to try coffee.

Day 33 (3/4/13)

Day 33 keto diet journal entry - carbohydrate cravings

Notes: Woke up lightheaded, but otherwise ok. Strong carbohydrate cravings towards evening. Didn't even try to fight them.

Day 34 (3/5/13)

Day 34 keto diet and sinus congestion

Notes: Woke with mild low back pain and mild sinus congestion (dairy protein effects from ice cream) Above average appetite with carb cravings all day.

Day 35 (3/6/13)

Day 35 keto diet and carbohydrate cravings

Notes: Hungry all day long—ate about twice as much at each meal as I normally would, and still couldn't get the carb cravings or hunger to go away, so I gave in again to the carbs . . .

Day 36 (3/7/13)

Day 30 keto diet journal entry - adaptation

I feel fine this morning, actually—that lightheaded/dizzy feeling is completely gone, finally! Maybe I just needed a lot of calories yesterday, who knows? I want to try to get these carbs back out of my diet . . . maybe if I stick with the coffee for another day or two it will help to resist them. Anyway, I'm curious about coffee's effects on blood sugar, so I tried a mini-experiment before breakfast.

  • Morning blood sugar: 105
  • Blood sugar 1 hour after 1 cup of unsweetened black coffee: 94
  • Blood sugar 2 hours after coffee: 88

Well, plain coffee certainly didn't raise blood sugar, but in order to know whether it lowered blood sugar, I'd need to do a control experiment where I test my blood sugar one and two hours after drinking water, to see if the drop was just the natural effect of not having any calories.

Ketogenic diet blood tests: results from 2/28/13 (day 29)

I wish it had occurred to me to have blood work drawn just prior to starting my experiment. Instead, I am using test results from last April for comparison. At that time, I was eating a modified Paleo diet of mostly meat, plus a few fruits and vegetables. I limited calories to 1200–1400 per day, and exercised vigorously for 45 to 90 mins, 5-7 times per week. I've only listed those comparison values that are significantly different from last year's results or are of particular interest. Otherwise you can assume they were about the same. Abnormal values from 2/28 are in red.

blood tests on ketogenic diet

a I finally achieved Seyfried’s zone of metabolic management on the last day that I could tolerate the experiment
b Estimated average glucose over past 3 mos = 103
c “Normal” range is based on BMI. I’m pleased that mine is lower—lower is better. Would have been interesting to see a pre-ketosis value for comparison.
d Different labs listed different normal ranges
e Test results from June 2012

Reflections on "abnormal" ketogenic lab results

Blood sugar & insulin

Clearly this diet had powerful effects on blood sugar and insulin levels. According to the lab, both of these values were abnormally low. It is certainly possible for blood sugar to be too low, and we do need some insulin in our bodies at all time, but lab ranges for normal values tend to reflect the normal values found in the population—not the ideal ranges associated with optimal health. Was my insulin too low to be healthy, or just lower than it is for most people?

Homocysteine and vitamin B12

It is strange that both of these were elevated, because they often tend to go in opposite directions. In fact, LOW B12 levels are a commonly linked to HIGH homocysteine levels—clearly not the case for me. Other vitamin deficiencies can also be associated with high homocysteine levels, including low B6 and low folate. I don't have low folate levels, and I did not have my B6 level checked, but B vitamins are plentiful in animal foods, so I doubt my B6 would be low.

It makes sense that my B12 level would be high, because my diet is very high in animal foods, which are rich sources of B12. I am not aware of any negative consequences of having a somewhat higher level of B12 than the average population. In epidemiological studies, high homocysteine levels have been observed to be associated with higher risk for heart disease, but keep in mind that epidemiological studies cannot prove cause and effect (for more info about this topic, see my brief post about this: "The Problem with Epidemiology.") In clinical studies, lowering homocysteine levels turned out not to reduce risk for heart disease. Some people have genetic differences in enzymes that cause homocysteine to accumulate, so perhaps that is true for me.

Anion gap

This just means that there are extra charged particles in the bloodstream that were not directly measured. The ones that are directly measured are sodium, chloride, and CO2 (carbon dioxide). It is common for people in ketosis to have a bit of an anion gap because ketones are charged particles. Note that my CO2 level was normal, which means that I was in ketosis, not ketoacidosis. In ketoacidosis, the CO2 level would be LOW.

Cholesterol and triglycerides

Elevated total cholesterol or elevated LDL do not concern me (for more information about this, please see my cholesterol page). I care much more about my HDL (pretty good, but it was even better last year when I was exercising regularly) and my triglycerides (again, also pretty good, but even better last year).

Apolipoprotein B

Nicknamed "ApoB" for short, Apolipoprotein B is a fatty protein on the outside of LDL particles. The more ApoB you have, the more LDL particles you have. Higher numbers are usually considered bad, because what we want are small numbers of big fluffy LDL particles, not large numbers of small, dense LDL particles. It is unclear to me precisely how ApoB and LDL particle size are related, but my basic understanding of this relationship is that people with insulin resistance are more likely to have high ApoB values.

I believe I am more insulin resistant than the average person, given my high fasting and post-meal blood sugar values when eating a diet containing typical amounts of protein and carbohydrate. It seems that high ApoB levels are not uncommon in people eating a ketogenic diet, and that cardiologists are unsure whether this is unhealthy. Listen to Jimmy Moore's interview with Dr. Thomas Dayspring for his take on this issue.

Thyroid tests and ketogenic diets

My TSH (thyroid stimulating hormone) level was normal, and that is the test that most doctors currently use to screen for low thyroid hormone activity. However, my circulating levels of T3 (the most active form of thyroid hormone) and reverse T3 (the deactivated form of rT3) are both "abnormal", and most importantly, the ratio between them is very low. This may help to explain why my energy was low during this diet, although I have to keep in mind that I have never had T3 and reverse T3 measured before, so there is no way for me to know what my levels were before this diet.

When the body is stressed or undernourished, it will work to lower thyroid hormone activity to slow metabolism. It is definitely possible that my low thyroid hormone activity could have been caused by an extreme ketogenic diet. Whether low thyroid activity (without symptoms of hypothyrodism) is ultimately a good or bad thing for the body is debatable, as some (most notably Dr. Rosedale) believe that a "cooler" metabolic rate may be beneficial.


Folate (aka Folic Acid) is famous for being found in green leafy vegetables. One problem with my 90-day all-meat diet last summer was that my folate level dropped to below normal. I tried to supplement with folic acid tablets but couldn't tolerate them, so I added occasional chicken liver to my diet last summer and that seemed to correct the problem.

Vitamin D

My levels have improved since last summer, when I started taking Vitamin D supplements.

Where to from here?

I continue to believe in the promise of ketogenic diets for overall health, mental health, appetite control, and weight management. However, I personally was not able to tolerate the diet recommended by Dr. Seyfried for cancer treatment—at least not as I had constructed it. If any of you have ever reached ketones of 4.0 and blood sugars of 55-65 and had a different experience, I would love to hear from you. I hope that people with cancer may achieve important benefits from a less extreme ketogenic diet, but I do not know if that is true.

I went back through Seyfried's book again last week and found that, in one place he refers to a target ketone zone of 3.0 mM to 5.0 mM (whereas he usually used 4.0mM as his minimum target zone); 3.0 would have been easier, because I could have eaten a little more protein. Theoretically, a standard ketogenic diet (aka "nutritional ketosis, such as that recommended by Phinney & Volek, which aims for ketones in the 0.5 to 3.0 mM range) or the Rosedale Diet (which does not recommend testing ketone levels at all), should provide benefits to all and should not be harmful, but whether they pack the punch necessary to fight cancer or control seizures is unclear.

For the sake of my own future health, and to satisfy my intellectual curiosity, I would like to try a standard ketogenic diet, and had hoped to gradually transition into such a diet this past week without going out of ketosis, but unfortunately, that didn't happen.

Ketogenic diet experiment, take 2

So, what to do now? I'd like to try moderate nutritional ketosis using the mostly-meat diet that worked so well for me last summer. However, I don't know if I'll be able to limit my protein enough to get my ketones into the target range without getting hungry.

Nutritional ketosis take 2

I know people who have been very successful at managing weight and controlling appetite using a standard ketogenic diet, including a friend of mine whose progress has been inspiring to me. She has been following a ketogenic diet since October and agreed to let me post about her experience. Her post provides more promising and hopeful results than those I personally have yet to offer. . . . Read a terrific guest post by Anne, who successfully and happily lost weight using nutritional ketosis.

I hope you have enjoyed witnessing the launch and demise of my ketogenic Hindenburg . . .

If you are interested in starting a ketogenic diet yourself, see my online guide: "Ketogenic Diets 101."

Recommended ketogenic diet resources

  • Cancer as a Metabolic Disease
  • Art and Science of Low Carb Living book cover
  • The Rosedale Diet book cover

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