Most women do in fact reach ketosis while pregnant. They can't keep anything down due to morning sickness, and the body burns ketones as a rusult. This often lasts for 12 weeks during the time that the baby undegoes the most cellular differentiation, the same time the baby is most suseptable to environmental influences. The concern here is not that mom is in ketosis, it is that her body is being depleted in order to support the baby. Provided that mom is being adaquetly nourished, I dont see what detrimental effects ketosis would have on pregnancy. If there was, wouldn't it show up in these critical weeks?

Questionable - almost every living traditional society today has specific "dietary specials" they feed newly married women in their tribes - those trying to get pregnant - and that continues when they are pregnant and lactating. The foods offered to these women - high carb foods - honey, roots, sweets made from fruits and honey, etc. Nope, they're not feeding them grains since most of these societies don't eat them, but they do practice a "dietary intervention" that interestingly provides a higher level of carbohydrate in the diet to women. I'm pressed for time - but did some extensive research when I was pregnant and I'll post more later on the subject!

I'm not sure who told you that early in pregnancy *most* women are in ketosis because of morning sickness, or any other reason, but it's simply not true - even if they're controlling carbohydrate as long as they're eating about 72g of carbs a day (net minus fiber) or more. Pregnancy does indeed induce ketosis late in pregnancy - it's simply not an issue for the vast majority in the first trimester or well into the second.

Whether ketosis - and let's be clear here, I'm talking continuous ketosis, not the very normal tettering ketosis that almost all pregnant women will experience later in their pregnancy - is harmful to human pregnancy is unknown.

Animal models are clear - continuous ketosis is harmful to an embryo, a fetus and a breastfed baby animal receiving milk from its mother in ketosis. The list of "unfavorable outcomes" range from birth defects to failure to grow properly in utero, from liver problems to lower milk production and poor energy utilization, from inadequate nutrient supply to low bone density in the baby animal, from higher rates of spontaneous abortion (miscarriage) to pre-term labor resulting in low birth weight animals.

These are serious issues and if the animal model even begins to touch on the risks to a human pregnancy, it's clear that one does not want to be in continuous ketosis while trying to get pregnant, when pregnant or when lactating....it's too risky given the large amount of data known in the animal model.

On the other hand, ketosis - that is tettering in and out of ketosis - while pregnant does not appear to be a negative, is part-and-parcel to the later part of pregnancy, and in fact, during labor most likely is important for the mother to have the energy to go through labor and delivery when eating becomes a real challenge (most doctors won't let you eat anyway, but even if you try to eat, odds are you're just going to throw it up).

When DH and I were TTC, I was already eating "controlled-carb" since I'd been maintaining my weight loss for more two years at the time - so I wasn't at risk for continuous ketosis since I was above the usual 60g net threshold for continuous ketosis.

When I did get pregnant, my OB gave his blessing to continue eating controlled-carb, warned I'd gain more weight than an "average" pregnancy even with controlling carbs (which I did) and only made me promise not to dip below 70g of carbs each day (net minus fiber) through my first two trimesters and increase to at least 100g of carbs (net minus fiber) in the last trimester IF I was in ketosis more than not - I wasn't, but I wound up eating more carbs anyway - averaged probably 125g a day (net minus fiber).



If it did show up it would be a miscarriage and there simply isn't data to support the assumption that continuous ketosis doesn't factor into the picture or is harmless. What the data does show is that ketosis inhibits appetite, resulting in eating less calories - pregnancy requires more calories and if you're having a hard time getting them in at a level to maintain weight, wouldn't you think it would be more difficult to increase calories to support a pregnancy too?

Add to that, low-carb diets are often inadequate for critical essential nutrients. Sure you can pop a multivitamin, but no one is going to argue that food is your best source for essential nutrients since food also is packed with the co-factors and a spectrum of nutrients that complement each other together rather than in isolation. Unless you're really careful and know how to plan to meet pregnancy requirements with your diet, you're going to be robbing your body and the growing fetus of nutrients you need.

Then there's the issue of glucose requirements for the fetus - if you're not eating enough carbohydrate to support the glucose requirement of the baby, you're going to be making it with gluconeogenesis from protein. Considering our finite capacity for eating protein, you're taking a risk here since if you simply "hit the protein wall" before you eat enough protein for GNG, you're going to cannibalize your muscle to make glucose for the baby - no way around it.

There's also the issue of ketones passing to the baby for energy utilization - from animal models it does not appear that the developing fetus can use the maternal ketones for energy and the data shows they build up in the developing fetus liver, leading to malformations of the liver and/or jaundice at birth. Is that a risk you'd want to take? I don't think so...

Given the potential risks - I totally agree with the recommendation most OB's (who are open to or advocate controlled-carb) make to increase carbs to a certain level to avoid continuous ketosis...we simply don't have any data to suggest it's harmless in pregnancy from day one. Increasing carbs up to a level to avoid continuous ketosis isn't license to eat whatever - just make good choices and include some foods that are higher in carbs but still nutrient-dense, like sweet potatoes or legumes.

How do women in the Innuit and Masai cultures manage?

The Innuit actually have a few birth defects that are higher than expected or seen in other populations - congenital heart malformations - specifically ventrical septal defects (VSDs), and atrial septal defects (ASDs), long QT syndrome and primary biliary cirrhosis. They also tend to be much shorter in stature than other populations - but I don't personally consider that a "problem," ya know?

The Masai are notorious for gorging on honey when they come upon it and they're one of the societies that have a tradition in marriage where the woman is fed honey and cornmeal cakes to increase her chance to get pregnant in the marriage....she continues to be fed these foods when she's pregnant - and the tribe ensures it has these foods by preserving the honey and cornmeal in gourds throughout the year!

Interesting! Thanks Regina.

I always thought the short stature of the Innuit was probably a good thing for conserving heat.

With regards to the "morning" sickness thing, I found the best foods for settling my stomach were high in fat and protein! Yummy. But something like a muffin would make me feel so sick I cannot even contemplate eating one now, 6 years later.

I think their stature is just genetic - much like Asians are built differently than Europeans, so too the Inuit are built the way they are and there is probably a reason - like, as you say, perhaps conserving heat in their environment!

I want to add to the post I made last night - that in the various societies that do have some type of "diet intervention" for women when they're pregnant, the foods added don't make their diet "high carb" - it's an increase in carbohydrate but overall the diet remains very nutrient-dense with protein and fat sources still the mainstay, ya know?

There's also something interesting in the foods that are often added - and it's related to the metabolic effect of eating more carbohydrate - they increase appetite, so the pregnant woman is able to eat more calories than when she's eating mostly protein and fat. I think that's the underlying reason various traditional societies have adopted adding "sweets" and carbohydrate-rich foods into the diets of women trying to get pregnant and/or pregnant/lactating - it enables an increase in calorie consumption which helps support the pregnancy or lactation, probably to a greater degree than the additional nutrients or availability of glucose to cross the placenta play.

The thing I find so fascinating is that somehow they - the society - know that eating such a diet continuously, through all stages of their lives, isn't "healthy" for them - their "normal" diet is much richer with fats and proteins with only an occassional indulgence with food like honey for the majority of their lives, and they only adjust their diet for specific reasons, like pregnancy...and then return to their normal dietary pattern once the period of change is complete, like when a mother has weaned her child.

I just found an interesting paper about the Masai, with a little about their pregnancy practices: http://eprints.lse.ac.uk/archive/00...ography_PhD.pdf
Page 109

Unfortunately I can't copy/paste the PDF text but it talks about how they reduce their caloric intake drastically in the last trimester.

What an incredible find! Thank you for posting the link to it - wow, I have some reading to do!!!!

Or for that matter, how did every single human mother, until a few thousand years ago, manage?

Ketosis is often associated with starvation or under eating.
Are you sure it is ketosis that is harmful to an embryo, and not necessarily energy restriction?


Good point. Although, I think the appetite reduction from ketosis goes away when you are acclimated to them. So it's probably not a good idea to start a ketogenic diet in pregnancy since you will experience unnaturally high suppression of appetite.

For me ketosis has a much weaker appetite suppressant effect on my body than it used to. Being in deeper ketosis (example: I ate 30 carbs today being very active) is not that much different than how I feel when eating more carbs. The main differences is that hunger is perceived a little less vividly and usually comes with nausea. But, I still do know very well when I'm hungry. Appetite only gets really abnormal if I eat too many, at which I become unbalanced and excessively hungry; the more I eat the hungrier I get.

Of course I am also relatively low weight so my lack of high body fat might have something to do with why ketosis no longer suppresses my appetite (my body wants me to gain weight?) If ketosis appetite suppression ebbs and flows with body fat stores, then, I don't see the danger here either as overfat people ideally should eat less to lose weight, and underfat people should eat and gain, right?

I think LC diets are only inadequate if you're under eating. LC food is more calorically dense so it is harder to get the nutrients, but, if you eat generously that problem is mitigated. I eat a lot of bones and I think it's probably a much better source of minerals than all that dairy we are told to eat .


I agree it's probably better to be safe than sorry. I am suspicious though that the evidence against ketosis in pregnancy is as firm as you say it is.

Thing is, they don't test theories out on pregnant women; it's not acceptable in our society. Nobody is going to run a clinical trial and have a bunch of pregnant women eat extremely low carb just to see what happens to the fetuses. So the animal models are all we have to go on for evidence.

I couldn't get that Masai link to work, but I searched on Google and matched the Google text sample to this link here. I can copy and paste the relevant bit:

The defects are probably do to increasing PCB contamination of their food supply. I suspect this has been a problem for a long time and we are just seeing the results.

http://www.chem.unep.ch/pops/POPs_I...es/ottawa-1.htm

http://www.ourplanet.com/imgversn/124/watt.html

I'd say we don't know - we know the pressures of natural selection have resulted in (micro) adaptions, in that when a variable was unfavorable, genetic adaptions occur over generations...for example, we have multiple redundancies to ensure stable blood sugar levels (specifically to raise blood sugar) and only one to lower blood sugars, thus we can consider low blood sugar was the risk/threat to survival across the species - high blood sugars were not, ergo high intake of food that produced persistent elevated blood sugars was not a threat, but ability to find enough to keep blood sugars normalized was...the result - redundancy to protect the survival of the species with internal mechanisms/pathways to boost blood sugars as necessary - most notable, gluconeogenesis (GNG).

What we don't know is if long-term selection outcomes favored those able to find and eat more carbohydrate or protein sources with higher glucose conversion or not - the redundancy in our metabolism to maintain blood sugar would suggest that failure to consume food to maintain blood sugars was taken care of metabolically with GNG and other metabolic pathways....what we can't say is whether these were favorable or unfavorable during pregnancy - we simply can't determine if the result in the long-term process of adaption was to kill the line over generations in those that repeatedly had to utilize the metabolic pathways to sustain stable blood sugars or those that had reliable food sources to maintain blood sugars. I wish we knew!