I’ve received the question numerous times, and last month several readers raised the issue in my “Ask Me Anything ” post. For all the innumerable benefits of the Primal Blueprint diet, there are a handful of situations that oblige a few modest accommodations. In the past I’ve suggested Primally-minded adaptations for endurance athletes . Today I’ll take up the question of nursing. Do the long-term, intensive demands of breastfeeding require modification of the typical Primal diet? What special considerations are there for nursing mothers? And what about specific scenarios readers have mentioned: ketones, reflux, ammonia-scented urine? There’s a lot of Primal ground to cover today, so let’s jump right in. But first a reminder that I’m not a doctor and that everything on this site should be viewed as my opinion and not medical advice.
First, a little background. Nature made the nursing process extremely efficient, which is great for baby and potentially not so great for the mother. The body not only prioritizes nutrient intake for breastmilk but in fact scavenges the mother’s stores, leaching calcium from the mother’s bones, for instance. Even under starvation conditions, the body still produces breastmilk with a remarkably nutrient dense profile. As comforting and ingenious as this phenomenon might be, it’s important for mothers to nourish their own health and wellbeing during these months. Although a shortchanged day here and there won’t do much, over time deficiencies can develop – especially if you’re practicing extended breastfeeding. As a result, research suggests that breastmilk displays a remarkably stable nutrient profile regardless of the mother’s food intake. Nonetheless, some nutrient levels are more dependent upon dietary intake because the body simply doesn’t store these in any substantial volume. As a result, optimal nutrition is crucial both for the baby’s development and the nursing mother’s overall health.
In keeping with these substantial needs, the more nutrient dense a nursing mother’s diet can be, the better. Of course, there are those additional 500-700 calories required for breastmilk production. (I remember Carrie  being ravenous during those early months of nursing.) Yet specific nutrient needs escalate throughout the exclusive nursing duration as well. With only the basic RDA intake, women can stand to lose substantial bone, muscle and other organ stores.
For a comprehensive breakdown of nutritional secretion in breastmilk as well as RDA comparisons, check out this book  from The National Academies Press. The report, for example, illustrates how an average nursing woman who eats only the basic RDA for protein  can expect to lose approximately 20% of her lean tissue to cover the nursing related shortage. The most common deficiencies for nursing women are zinc and calcium. Additional “at risk” nutrients include magnesium, thiamine, vitamin E, vitamin D , B6 (especially if mothers have used oral contraceptives prior to conception), and iron (if/after menstruation resumes during nursing). Other nutrients like folate are of concern because the body keeps no ready stores and excretes any excess. In considering ample dietary intake, it’s important to realize that absorption efficiencies vary nutrient by nutrient. Protein absorption, for example, comes in at around 70%. Zinc absorption has been measured at approximately 20% in the general population, but some research suggests  a higher absorption rate in nursing mothers.
Now for the carb controversy. When it comes to low carb diets and breastfeeding, the conventional message sounds very familiar: back away or risk great peril. There’s little research on this topic, but rest assured there’s no support for the anti-low carb alarmism. In the absence of modern confirmation, reason and evolutionary precedent can lend context. Prehistorical mothers always breastfed, of course, and there’s no reason to believe their diet was consistently or substantially different than anyone else’s of their time.
Given the impetus toward nutrient density, carb-based foods (like grains ) remain relatively poor and unnecessary choices. The nursing mother has greater energy expenditure than she did before; however, her body’s natural metabolism and conversion abilities function just as well if not better. Additional clean protein sources and natural, intact fats not only provide excellent nutritional value for their volume; they offer satiation, a feeling hard to come by in those early post-partum months.
That said, I’m not one to suggest a no- or very low- carb diet  during exclusive breastfeeding. Although I know there are plenty of mothers who have successfully done very low carb diets throughout their nursing duration, I generally suggest staying in the moderate carb range (100-150 grams/day) for a number of reasons. Although the presence of ketones , some of which can potentially be passed through breastmilk, might throw off the taste of a mother’s milk, I haven’t read anything to suggest that they compromise the health of the baby. The real issue, I think, with going extremely low carb is nutritional. It’s just flat out difficult to obtain fully rounded nutrition from very low carb diets. Cutting carbs too low generally means doing away with not just sugars and grains but antioxidant rich vegetables and fruits. With the increased needs for vitamins and minerals during nursing, I wouldn’t suggest giving up or cutting back on their best sources. It’s infinitely better, I believe, to get the full scope of nutrition for you and your baby. And though I believe wise supplementation  has an important role for modern living, I don’t see supplements as stand-ins for a nutritionally comprehensive diet. A quality multivitamin and mineral supplement as well as additional omega-3  can offer a little extra assurance, but it can’t take the place of a solid diet itself.
Second, I tend to think that weight loss should be pursued carefully and selectively during breastfeeding. If a nursing mother is carrying a substantial amount of excess weight, it’s a reasonable choice to wisely – and Primally – diet once her milk supply is fully established (at very least six weeks but more conservatively twelve weeks’ time). Even in these circumstances, experts generally recommend not going below 1800 calories/day for the sake of maintaining adequate nutritional intake for the baby and basic needs of the mother. I would suggest a bit more as a rule of thumb. Nursing is a time to go a little slower on weight loss, especially because rapid loss can potentially release built up environmental toxins from fat stores. If extra weight is modest or simply pregnancy related, I recommend letting time take its course. Target your eating with healthy Primal fare , but I wouldn’t suggest restricting your caloric or carb intake for quick fat loss. The caloric demands of nursing itself, the moderation of a Primal diet plan and as much regular activity as possible will consistently and safely chip away at the remaining excess pounds.
Finally, to those final specific questions about Primal nursing…. A lot of babies have reflux, and it can sometimes be related to food sensitivities. If it’s a significant or ongoing problem, it’s worth eliminating certain food groups for a couple weeks at a time to see if it makes any difference. Although gluten and dairy get the most attention and warrant initial test runs, you might want to consider doing the same test runs with nuts , nightshades , eggs , citrus and any remaining soy  in your diet. Readers might have other tips for sensitivities they’ve discovered. As for the ammonia-scented urine, it’s likely an issue of dehydration. Try adding a couple extra nursing rounds for a few days. The baby won’t take as much in but will get more of the watery foremilk to fill his/her fluid needs. Also, be sure to drink plenty of water yourself during these times. Nursing requires additional water intake, and it can be easy to skimp when you’re balancing the many responsibilities of early parenthood.
Thanks for reading, everyone. Be sure to weigh in with your thoughts, tips and additional inquiries about nursing while Primal. Keep those questions coming, and have a great week!