“Young mother nearly dies from a low-carb diet”
in Potential LCHF problems 
Can it potentially be life-threatening to breastfeed on a strict low-carb diet?
While this seems to be exceedingly rare – four published cases ever, all of which ended well – it’s apparently possible to develop ketoacidosis while breastfeeding on a strict low-carb diet. The same thing can happen due to starvation.
Don’t do a strict low-carb diet when breastfeeding – and make sure to eat enough in general.
Correction
Note that the ending of the MailOnline article is misleading. There’s normally no need to “see a doctor immediately” if the breath starts smelling of acetone on a low-carb diet. That’s a common sign of normal ketosis, which is completely safe under normal circumstances (unless you’re a type 1 diabetic, then it signals that you need more insulin).
When breastfeeding however, it’s probably wise not to eat so strict low-carb that you get that smell. Let the weight loss take some more time and go for a more moderate, non-ketogenic, low-carb diet while breastfeeding (50+ grams of carbs per day). And make sure you eat enough. It’s hardly worth taking any health risk at all for losing weight faster.
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I’ve just recently written more extensively about the rare risk of ketoacidosis when breastfeeding on a strict low-carb diet:
If not, this research would have to be talking about alcoholic ketoacidosis or starvation ketoacidosis. The former of which would require the nursing mother to be drinking alcohol and the latter would require the nursing mother to be fasting for 24hrs.
So surely better advice would be to avoid fasting and alcohol?
Or, are there confounding factors such as a second pregnancy while breastfeeding?
Seems a little premature and dismissive to be saying that because of 3 extremely-rare cases (that all ended well) the entire population should avoid something. If we took that attitude in everything there would be no cars on the road and we couldn't eat ANY food.
Only been doing it for a month but feeling great. Not really concerned about weight loss, lost 5 kilograms in the first week and now seem to be stuck, but clothes getting loose, so happy. Will keep doing it (but not checking the scales for a while :-))
"In late pregnancy, glucose is directed from normal bodily functions to the nutrition of the developing calf. As lactation starts, glucose is essential for the formation of lactose (milk sugar) and milk fat. The requirement for glucose is at such high levels that the blood becomes low in glucose (hypoglycaemia). Fifty grams of glucose is required for each litre of milk with a 4.8% lactose test and 30 grams for each litre of milk with a 4% fat test."
http://agriculture.vic.gov.au/agriculture/pests-diseases-and-weeds/an...
We ain't so different from other animals.
Otherwise, in the modern day society of excess glucose, it's probably not a bad idea to cut some, just to get us back to a more natural state.
We do recommend increasing carbs while breastfeeding.
https://www.dietdoctor.com/low-carb/when-breastfeeding
Some people will never understand how much of a struggle weight loss is. How a scale can determine if you hate yourself until bedtime or if you reward yourself with a zero calorie, zero carb drink. Some people will never get how body dysmorphia(sp?) attacks you and takes over even when you're trying to fight it. Sometimes, the devil wins.
Megan, thank you so much for sharing this deeply personal story. You are not alone in the struggle with body dysmorphia. I passed your story along to our team. Perhaps they will be able to address this issue in the future.
My experience is opposite, I gained weight after giving birth. Some women have such metabolism at breastfeeding.
But I think that stress of giving birth (birth itself takes a toll on woman's body), especially complicated as mine was, poor sleeping etc. change metabolism, so I can't loose weight easy as before.
Maybe we shouldn't focus on dieting when our bodies are struggling not to lose weight.
(I limited calorie intake on cca 1800 kcal 2 and 4 months after giving birth, both times started losing milk supply, so stopped dieting).
I focused on healing first, eating healthy and moderate. I avoid sugar and processed food, and eat when I am hungry.
Now, 8 months after giving birth, I think my metabolism and stress levels are going back to normal. I started to slowly lose weight, I am still breastfeeding, not losing milk supply.
Be patient.