Breast Milk Production Basics
Understanding milk production deceptively simple, but the actual process of making milk is quite complicated.
And while parents don't need to have a deep understanding of the physiological processes of milk production, most new parents desire to learn and benefit from knowing milk production basics, and the factors that can influence it.
To make that process (hopefully) more straightforward for you, I've answered the most commonly asked questions- and addressed the most frequently misunderstood concepts- to aid in your understanding of how your breasts make milk.
Why is breast milk made?
Milk production is the continuation of a metabolic change that began after conception, resulting in a biologically active fluid that sustains life.
That may be a wordy, possibly ew inducing way to describe the purpose of mammalian milk, but it is accurate. The sole purpose of milk is to keep babies alive and provide everything they need to thrive until they're able to eat additional food sources.
Milk changes depending on babies' needs. In the days after birth, when protection from unknown bacteria and viruses is of utmost importance, colostrum production meets the immune protection aspect needed for survival.
Within the first few days post-delivery, your milk volume will begin to increase, and changes to milk composition will occur. Though the same "ingredients" are present, the amounts of each will change to meet the nutritional needs of your baby best.
Anytime you or your baby is exposed to a pathogen during the duration of your lactation journey, your body will send the perfect factors to help reduce the severity of whatever illness that may develop.
Lactation, being a tailored metabolic state, also changes the way particular cells work, reducing the likelihood of experiencing a variety of diseases throughout your lifetime.
TLDR; We make milk because we're fantastic, and it keeps our babies alive and provides us a biological benefit over our lifetime. How cool!
What is my milk supply?
Your milk supply is the amount of milk you make in 24 hours.
Milk supply is different than the amount of milk your baby needs, which is, on average, about 30 ounces per day. Some parents will make less than 30 ounces per day; others double that.
The amount of milk you make will depend on many factors. Still, the general idea of maintaining milk supply is that production will ramp up - or downscale to- the demand placed on the breast via milk removal frequency and quality of breast drainage.
In short: Your breasts will make as much as your baby needs assuming that you are feeding on demand and that your baby can effectively remove milk.
Key Terminology
Storage capacity
Storage capacity refers to how much milk your breasts can hold. The capacity of your breasts will determine how frequently your baby needs to eat to meet their daily intake needs and how much time can pass before you begin to cause a decrease in milk production.
Those will smaller storage capacities may find their babies eat super frequently. (Example 12 times or more)
Those with large storage capacities may find their babies eat a little bit less often. (Example 8 times or more)
Those with larger storage capacities may also be able to go long periods between feedings without feeling super engorged, whereas those with smaller capacities may feel full fairly quickly.
Where ever you land on the spectrum of storage abilities, baring any underlying medical/health issues, you will meet your baby's daily intake needs given you feed as often as your baby asks.
Rate of milk production
The rate of production refers to the speed at which milk is produced.
Empty breasts make milk the fastest. Full breasts may completely shut down milk production (temporarily).
Though your breasts are NOT like a cup, it may be easier to understand if you picture an empty cup. When the cup is empty, and you begin to fill it of your beverage of choice, the rate at which you pour is increased. As the glass fills up and the risk of overflowing increases, the speed is downgraded till eventually, you stop pouring.
In keeping that vision in mind, it may be easy to see the principle behind why empty breasts make milk the fastest.
Why is the rate of production significant for new parents to understand?
In reality, it has little practical impact.
A more important concept to understand may be that the signal for your body to make milk is nipple stimulation either from your baby's nursing or milk expression.
So as your baby is removing milk, your body is hard at work making more milk. Not only does it explain why they say your breasts are never truly empty, but also why when your baby asks to eat again soon after they finish eating, there is milk available for them to drink.
Milk Output
If milk supply is the amount of milk that is made in 24 hours, and storage capacity is the amount of milk your breasts can hold, then milk output is the amount of milk that is expressed at any given time.
This output may or may not be close to your breast's storage capacity, may vary throughout the day, and is not an indication of how much milk your breasts make in a day.
Confusing, I know.
If you are feeding on demand without expressing milk, how much your output is will be equal to the volume your baby ate at that time.
If you express after you breastfed, your output will be whatever is remaining that is not in your baby's belly and can be removed.
If you are exclusively expressing, your output will be whatever you're able to remove at that specific pump session, and like pumping post feed, it will be influenced by a wide range of factors.
In summary, milk output is the volume of milk removed from the breast and is only just a snapshot of what occurred in that specific moment.
Now moving on to the most frequently asked questions regarding milk production...
How can I increase my milk supply?
The most straightforward and basic answer is to remove more milk by increasing the frequency of feeding/pumping.
We know that milk production meets the demands placed on the breast, so by increasing that demand, the supply adjustment should follow, and within the next couple of days, daily milk volume should increase.
Even with an increase in daily milk production, you may or may not notice a difference in milk output. You can impact your milk output per session by following these strategies, and it's may not be necessary for you to try to increase your milk supply.
If attempts at increasing the daily volume through increasing milk removal frequency and despite reading the pump tips mentioned above or this flange sizing guide, you see little to no increase in supply, it's time to contact an International Board Certified Lactation Consultant (IBCLC).
Understanding milk production deceptively simple, but the actual process of making milk is quite complicated, and an IBCLC will be able to help you troubleshoot and get you on a care plan based on your specific circumstances.
Why is my milk supply low?
If you're looking for more information on possibilities for low milk supply, I encourage you to hop over to this low supply overview, which will outline all the possible reasons for low production.
Why might people want to increase milk supply?
There are as many reasons for wanting to increase milk production as there are people on this planet. The most common reasons I see include
They worry they don't make enough for their babies
They produce less milk than their baby's daily intake need
They have more than one baby and desire to exclusively human milk feed them all
They want to build a stash
They want to become a milk donor
Isn't there a supplement or medication that will help me produce more milk?
Yes, and no.
No supplement or medication will increase milk production in the absence of frequent milk removal. Additionally, there is no universal supplement or medication that will work for every person in increasing their milk supply.
However, there is a wide range of lactation supporting or "milk boosting" foods, supplements, & medications (galactagogues) available.
Based on the underlying cause of low supply and one's medical history, supplements may be an included tool in a tailored care plan.
Read Next: Why Foremilk & Hindmilk is not a thing.