Before I started the Carb Nite diet, which is a cyclic ketogenic diet, I studied long and hard on the possible effects of being in ketosis while breastfeeding. Might it affect the quality of breastmilk? Might my milk supply go down? These would be unacceptable outcomes for me, as I’m committed to supplying my 6-month-old son with breastmilk as his nearly-exclusive source of nutrition.
So I read “Nursing and the Primal Blueprint Diet” from marksdailyapple.com, a website dedicated to the paleolithic diet (which is not necessarily ketogenic, but is usually moderately low-carb and can often be ketogenic).
I read forum threads like this one, where posters insisted that ketones either wouldn’t get into breastmilk or wouldn’t get harm the quality of the breastmilk.
I also talked to Dave Asprey, author of the recent Better Baby Book, who explained that the fat in babies’ brains is assembled FROM ketones in the blood. So how could a few ketones in the breastmilk be anything but beneficial?
In the end, it came down to trying SOMETHING. So I embarked on the Carb Nite diet and kept good records, watchful for any changes, problems, etc.
It’s now been 2.5 weeks since I started a cyclic ketogenic diet in the midst of exclusively breastfeeding my 6-month-old son. I can now say with confidence that consuming 30 to 40 grams of carbohydrates per day, effecting an 8% caloric intake from carbohydrates, has no effect whatsoever on milk supply.
Of course I can only speak for myself here, since I’m hardly a medical professional or even a scientific expert.
However, I have conducted my own scientific micro-study on the effects of eating an ultra-low-carb and ketogenic diet while exclusively breastfeeding. I tracked my caloric intake, keeping my macronutrient ratio to strictly 8% of calories earned from carbohydrates, and eating (as a guideline) my body weight in protein in grams (135, if you must know) every day. And I have been tracking my nursing time, my son’s weight, and my pumping output every single day since my son was 3 weeks old.
At this point I am highly confident in saying that being in ketosis — periodically — has absolutely no effect on milk supply.
I can’t say the same for being in constant ketosis, because I haven’t tried that yet. My diet has been cyclic: 3 days of burning off carbohydrate stores (non-ketogenic), 3 days of ketosis, and then one day of “carbing up” where carbohydrates are consumed in excess and stored for the next cycle.
I plan on staying on this diet for another 2 weeks at the very least, because I’m interested in the fat loss it purports to bestow, and I will be watching my milk output as I go through each CKD cycle.
In case you are curious, I am using MyNetDiary for my nutritional intake recording, and Total Baby for my nursing and pumping recording. I absolutely adore these programs as they seem to be extremely well-programmed (they don’t crash my “ancient” iPhone 3G) and their interfaces are intuitive. These programs save me time over writing things down on paper, and that’s not a compliment I ever give lightly!
Full disclosure: I am continuing to use the phytoestrogenic / phyto-oxytoxic herb fenugreek on a 2-weeks-on / 2-weeks-off cycle, because even when I was eating a “balanced” diet my milk supply has tended to be low, and this particular herb has given me measurable boosts in my milk production.