I received a great question about the problematic diagnosis of gestational diabetes due to a failed oral glucose tolerance test. Give this a read so we can dismantle pregnancy related nutrition.

Hey Robb,

My wife and I have been Paleo ever since I was “certified” in Portland last year:)

My wife is 8 months pregnant and has been dx with gestational diabetes (I truly believe its total bs and that the OGTT is inaccurate in so many ways that it is ridiculous, but I digress) We are using a birthing center with a midwife so it was a sad requirement that we consult with an “expert” in nutrition, which had to be the most frustrating 2 hour visit of my life (the RN who we visited with was diabetic herself and came in drinking a large diet coke…I threw an apple core in her waste basket and found multiple fast food containers…Im not judging…she then began to tell us how we were eating to “low carb” and how bad it was).

ANYWAY, my wife left with a glucometer (awesome) and she was told to check her sugars 4x a day for 2 weeks 1 hour after every meal and then send the results back in (BTW my wife does CFmoms and is 5?10 170…138 with out the baby, very lean and athletic).

So for 2 weeks we BOTH checked sugars, to compete, and all of our sugars were great, below 88 after 1 hour and fasting in the am high 60’s low 70’s, she faxed her sugars in and was immediately called by above referenced nutritionist and told that her sugars were “to low” and asked to eat MORE carbs (complex of course) and check for another week, so we made up sugars that were slightly higher and faxed them in and have not received a call since. We eat fairly strict, always unlimited quantity and to satiety, we have never felt better. I’m a Fire/Medic and will occasionally check my sugars at work for random reasons and several times have found my sugars in the low 60’s (no symptoms, feeling great)….and I’m aware this flies in the face of western medicine (we practice under our protocols that we cant leave a diabetic at home with bgc less then 80).

SO, my question is, based on your genius….what is to low (not according to current medical standards which seem to be on the high side)?

Thanks, Silky



If you are unfamiliar, the oral glucose tolerance test (OGTT) is a diagnostic test used to establish gestational diabetes. The thinking goes like this:

If you consume a large bolus (75-100g) of glucose and fail to clear it in a timely manner, you are insulin resistant and thus have “gestational diabetes” (GD). I’ve written on this topic before and the whole thing makes me want to lobotomize myself with a blunt instrument. It’s a tough and incendiary topic. On the one hand our medical professionals deal with a huge population of women who eat very poorly, never exercise and somehow still manage to get pregnant. Miracle that this situation is, biology makes things worse. During pregnancy the mom becomes even more insulin resistant due to an evolutionary adaption in mammalian-mom’s in which they become slightly insulin resistant to allow a positive flow of nutrients to the developing fetus via the placenta. If the mom was more insulin sensitive than the fetus we could end up in a nutrient scarcity situation due to nutrition flowing to the more ubiquitous tissues of the mom. Biology fixes this problem by making mom a little insulin resistant, effectively “pushing” nutrients to the fetus. Score one for biology! Problems arise however when our modern diet and lifestyle make this otherwise favorable adaptation dangerous. Too many carbs (particularly chronic fructose intake), autoimmune complications with lectins, loss of insulin sensitivity due to sleep deprivation and stress can drive expecting moms into gestational diabetes. From the paper linked above we have an interesting observation that severity of GD is likely determined in part by estrogen and progesterone levels. One of the key features of hyperinsulinism is a decrease in sex hormone binding protein (SHBP) which then makes estrogen more available to the tissues. Interestingly, this problem with estrogen is actually at the heart of most female infertility, but that is a topic for another day (or a book…)

Now’s My Chance to Party!

As if the above was not bad enough, many moms-to-be decide “this is my chance to eat anything…I’m going to get fat anyway!” We now have a really terrible situation for the moms, unborn kids and the medical professionals who deal with this everyday. These mom’s are laying down the genetics for their kids in such a way that kiddo will be prone to poor insulin control, diabetes and a host of related problems throughout life. In geek-speak our phenotype (the physical manifestation of our genetics) begins in uttero and that sets the tone for the rest of our lives.

So far so good? Great, now let’s go to Bizzaro world (ours) and see how a lack of evolutionary understanding on the part of our medical professionals can derail an otherwise good situation. In the example above “paleo mom” has been eating great and if we ran an A1c (a measure of blood glucose over time, much more valuable than the OGTT or blood glucose measure) we’d likely find she has low, BUT HEALTHY blood glucose levels. She is fat adapted, not insulin resistant and can thus run many of her tissues on fat. That folks, is good. But what happens when she is given a bolus of raw sugar, much larger than anything she, or her developing fetus have ever seen? Well, she has trouble clearing all that sugar. This may give people a headache, but some of this mom’s tissues are “insulin resistant” but healthy because they run on fat.

Smoke’em if You’ve Got’em

A “sugar burner” will see decreased physical and cognitive performance quite quickly compared to a fat burner. Why? Because that fuel (glucose) is comparatively limited and if most of the tissues are running on glucose one must rely on constant feedings or face a blood sugar crash. Folks with this problem must re-feed every 2-3 hrs to avoid “hypoglycemia”. In extreme situations this hypoglycemia could result in coma or death and this is part of what the medical folks are worried about in this gestational diabetes situation. But just like standard insulin resistant type 2 diabetes, they botch the solution. What they are missing in this situation is this paleo-mom is buffered against the vagaries of blood sugar changes because her main fuel source is fat. In chemistry a buffer is the salt of a weak acid or base that prevents changes (up to a point) in the pH of a system. This is pretty handy in biological systems that operate within very tight acid/base ranges. In economics and statistics a similar phenomena is called an attractor. Biological systems, economies and other dynamic processes function well with “buffers” as it prevents high’s and low’s that could destroy that system.

Where things are falling down is this mom is not having a blood sugar management issue typical of most people coming through the door of hospitals. Her metabolism is running on a comparatively “infinite” fuel source (fat) and she and her developing baby are doing just fine, thanks. At least until they were exposed to a 100g bolus of raw glucose (which they do not clear quickly, but this is a normal adapation to a lower carb intake) and are then told to increase her carb intake until she becomes….a SUGAR BURNER!!! The recommended diet change would drive average blood glucose up, increasing inflammation and advanced glycation end products typical of elevated blood glucose. Mom can now suffer legitimate blood sugar crashes due to an inability to access body fat for the preponderance of energy needs in her body. Thanks Doc!

Take a look at this study for some specific numbers. You will notice that glucose utilization for fuel went from .71g/kg/min in the baseline period to .50g/kg/min in the 4th week of adaptation to a ketogenic diet. Folks were burning 30% less glucose for their energy by the 4th week and this is just getting going. Those numbers improve with time and drop glucose consumption by upwards of 50% vs baseline. This means it actually gets damn hard to face a hypoglycemic event. Here is a nice closing paragraph from that paper:

“These findings indicate that the ketotic state induced by the EKD (EKD is a ketogenic diet with a maintenance level of calories) was well tolerated in lean subjects; nitrogen balance was regained after brief adaptation, serum lipids were not pathologically elevated, and blood glucose oxidation at rest was measurably reduced while the subjects remained euglycemic.”

This is a great paragraph. The ketogenic diet was not muscle wasting, did not unfavorably alter blood lipids, and stable blood sugar was maintained while decreasing total glucose consumption. If ketosis also fought cancer and reversed neurological disease ranging from Parkinson’s to Huntington’s it would be just amazing. Oh, wait…that’s exactly what ketosis does. HMMM.

May I have a slice of confusion, with a side of Ignorance?

So, the medical professional dealing with these folks is both confused and ignorant on a number of topics. Confusion grows from the fact that she is simply not used to seeing a healthy, fat burning mom walk through the door. Confusion and ignorance surround the use of the OGTT. And hopefully it’s obvious that the preferred management strategies for diabetes, be it gestational or otherwise, are ridiculous when we really think through the metabolic mechanisms. The two blood values that get doctors and dieticians in a fizz in situations like this are blood glucose and ketones. If they see ketones they assume a state of ketoacidosis but the two states cannot be any more different other than they both have ketone bodies in circulation. Ketoacidosis is not just ketone bodies but also decreased blood pH and typically very high blood glucose. This is a nasty situation but simply seeing ketones on blood work should not be all that is involved in making a determination of “ketoacidosiss.” The other piece, blood glucose levels finally brings us back to the original question: “How low is too low?” Well, we see numbers in hunter gatherers in the 60-70 range. In certain clinical situations of advanced ketosis individuals have functioned as low as 40ng/dl. From anthropological data and research on ketogenic diets I’d put a safe operating low end at 55-60ng/dl. Possibly lower, but the real take home here is simply how do you feel and perform? If you are having a blood sugar crash, it’s too low! But compared to what our medical establishment would like to see the fat adapted paleo-mom is likely fine at levels lower than commonly accepted so long as mom shows good A1C’s and simply feels good.

I’ll likely get a bunch of hate mail on this but there was a time when childbirth did not require OGTT’s and a host of other management schemes. Can childbirth be dangerous? Absolutely, but it would be nice if medicine adopted the position of using our best understanding of biology combined with the amazing advances in emergency care to offer the healthiest, safest experience imaginable for our moms and next generation of kids.

It’s time for the medical community to recognize the difference between health and pathology…and to actually advocate for health. We need a physician network that understands evolutionary biology and how a deviation away from our ancestral diet and life-way can create havoc for our health before we are even born. We, or at least our kids, deserve better than this.

Below is a photo of my nephew, Kayden. He is the cutest kid who ever lived. Or perhaps I’m biased as his uncle. He was conceived while his mom was eating paleo, and mom has mainly stuck with that both for him and her. All the way through pregnancy, breast feeding etc. Kayden is “off the charts” in every developmental category and although his parents are exceptional people, this is simply a phenotypic expression: Kayden is being compared against kids and moms who do not eat as well as they do. He will have a remarkable advantage throughout his whole life.