Is milk good for fertility?
Other than people who are lactose intolerant, we all pretty much drink milk. The recommendation from many nutritional authorities is 3 cups per day, but is milk good for fertility? Well, there seems to be a couple different trains of thought on this issue, so let’s break it down and figure out what’s best for you.
For years and years, I drank only skim milk. Anything with more fat just made me gag quesy as skim was what I grew up with. Plus it’s what the doctors, and heads of medical communities, recommend that everyone over the age of two drink and I’m a rule follower. I was told to drink skim milk, so dog gone it, that’s what I did.
It wasn’t until I started researching natural fertility and ways to boost my chances of getting pregnant that I learned there could be a correlation between dairy and my fertility.
Can milk increase fertility?
In a somewhat recent study, scientists found that women who consumed full-fat dairy were found to have a 27% lower risk of infertility. Women who consumed low-fat milk products twice a day were found to be twice as likely to not ovulate. This study seems to show that eating healthy fats, as are in milk, may be helpful in reproduction. Our bodies need this fat in order to maintain our cellular structure. Removing the fat from milk has actually been shown to cause an imbalance of hormones throughout the body, causing a failure to ovulate or produce a healthy egg.
So consuming full fat milk can definitely increase fertility in some women!
But not all milk is the same.
Downfalls of modern dairy
While I truly believe that all dairy farmers do care for the welfare of their animals, the simple fact is that the more animals a farm has, the more they need to resort to different ways to automate or change how they feed and care for them. A smaller dairy can more easily allow the cattle to roam the pasture during the day while bringing them into the barn at night. It would be near impossible to let out and bring in hundreds (or thousands) of cows every morning and night. So instead of letting them graze, many farmers keep their cattle indoors all day long in stanchion style stalls. Some barns are open to the outdoors, others are fully confined.
It seems that upwards of 80% of dairy cows are kept in confinement. Which is great for farmers as these cows actually produce more milk than their pasture counterparts, but it’s a disadvantage for the cows and for us as consumers. Keeping these cattle indoors may contribute to health and hoof issues as well as nutritional differences in the milk as the cows eat hay and grain instead of getting fresh green grass.
Cows now produce much more than what is needed to sustain a growing calf (by about 15 times), and they are also most often milked while they are pregnant which can change the hormonal composition of the milk depending on the trimester.
Another issue, that is hopefully becoming a thing of the past, is Recombinant Bovine Somatotropin, or rBST, a synthetic version of the Bovine somatotropin (BST). (also known as recombinant bovine growth hormone or rGBH) This hormone seems to be linked to early puberty in girls as well as causing hormone imbalances in older women. Milk from rBST treated cows also contains 2 to 10 times as much IGF-1 (insulin-like growth factor) as normal cow’s milk. This is significant, because studies have found the risk of prostate cancer for men over 60 years of age with high levels of IGF-1 to be eight times greater than for men with low levels. And the risk of breast cancer for premenopausal women with increased blood levels of IGF-1 to be up to seven times greater. (source)
Please note – many dairy farmers have told me that sick cows are taken out of milking service until they have been treated (usually with antibiotics), and no antibiotics are allowed in the milk when sent for processing. So no matter where you source your milk, you can be pretty sure that here in the US there are regulations that do keep you safe from antibiotics in milk.
A1 versus A2 controversy
In our modern dairies you’ll most likely find Holstein cows which produce milk that contains a protein called A1. This protein has been linked to dairy intolerance and many theorize that “lactose intolerance” is really the inability to break down this A1 protein.
“The A2 variety of beta-casein mutated into the A1 version several thousand years ago in some European dairy herds. Two genes code for beta-casein, so modern cows can either be purely A2, A1/A2 hybrids, or purely A1. Milk from goats and humans contains only the A2 beta-casein.” (source)
Some studies have also found that A1 protein may have a correlation with autism, type one diabetes, and some mental illness.
Here in the United States, the best way to get milk A2 content is to buy it from a dairy that uses A2-dominant cow breeds such as the Jersey, the Guernsey, or the Normande.
Is buying organic good enough?
Organic always seems to be a great option, but is it worth spending more at the store for it? It’s really going to depend on the brand and what farms the milk comes from! Some organic dairies are quite conventional and simply feed organic food to cows kept in confinement. Other farms let the animals graze outside.
Most organic milk I’ve seen is pasteurized using a process called ultrahigh temperature (UHT) in which the milk is briefly heated to 280 degrees Fahrenheit. This high temperature makes the milk stable for a very long time (it is actually shelf stable, but most stores sell it refrigerated as no one seems to want shelf stable milk…) but it also destroys many of the beneficial enzymes in the milk.
Pasteurization is the process of heating the milk to kill any dangerous bacteria that might be present. It became routine when dairies had very few regulations and the milk was often tainted – many people (especially babies) died from store-bought milk! Pasteurization in and of itself can be beneficial at keeping us safe (thought dairies are also much cleaner now!), but we do lose some of the benefits of fresh milk.
Some of the enzymes lost through heating include: lipase (helps digest fats) lactase (you need to digest lactose) and phosphatase (helps absorb calcium). Nutrients like folate, vitamins A, B6, B12, and C are also damaged along with the omega 3 fats. The proteins also change structure, but this is true of any cooked protein (beef, chicken, etc).
A study done in 1934, published in the Journal of Dairy Science, (back when they were first fighting to keep raw milk) showed a loss of 38% of the B complex vitamins. Another study done as a masters thesis at the University of Georgia in 1979 showed a 34.4% loss of vitamin B6, a 33.8% loss of thiamin (B1), and a 24.1% loss of folic acid. These losses were due just to heating the milk.(source)
Another study was done (didn’t write the year-sorry!) on rats fed either raw or pasteurized milk. It was shown that the heated milk was not capable of supporting the reproductive systems in these animals. Two female rats were fed a diet of sterilized milk for approximately 8 months. During this time they were each mated 15 times to male rats that had either been fed a raw milk or sterilized milk diet. No pregnancies were shown on any of these 15 occasions. Once a female was switched to a raw milk diet for 11 weeks, she was able to get pregnant when mated with a male, also from the raw milk group. (The Untold Story of Milk (available on Amazon))
Benefits of dairy from grass-fed cows
But we know from health and nutritional studies for humans that eating fresh foods is important, and the same thing goes for cows. Grass-fed cows simply produce milk with a better nutrient profile.
We know that milk from grass-fed cows is higher in nutrients like Vitamin K2 and cows that go outside have higher levels of Vitamin D in their milk – both are essential to a good fertility diet. It’s also 5 times higher in conjugated linoleic acid (CLA), a type of fat associated with a wide variety of health benefits, including immune and inflammatory system support, improved bone mass, improved blood sugar regulation, reduced body fat, reduced risk of heart attack, and maintenance of lean body mass. Grass-fed cows also produce milk with a healthier omega 3/omega 6 ratio.
Cow versus goat milk
Cows are simply mega milk producers and each cow can produce multiple gallons per day – it’s easy to see why it’s the preferred dairy animal here in the US! Plus, the cream naturally separates which makes it super easy to make butter (or ice cream). Nutritionally the milk from cows also contains more B12 and folate than goats milk, but cow dairy is also the number three allergy in children (may be due to the A1 protein).
Goats milk, on the other hand, is closest in structure to human milk and much easier to digest than cows milk, taking only 30 minutes to break down in your body, whereas cow milk can take 2-3 hours because of those larger fat globules. It contains a higher amount of medium-chain fatty acids (has 35% compared to cow’s 17%) and less lactose.
Another, less common option, is sheep’s milk. This is very similar to goat milk but creamier.
But can milk cause infertility?
I’ve been in this natural fertility world long enough that I have heard hundreds of women say that eliminating milk helped them balance their hormones. So let’s discuss a few ways that dairy may inhibit fertility:
- It may contribute to mucous production, especially in those with lactose intolerance. Excess mucous production in the reproductive system of a woman may make the sperm’s journey more difficult. Mucous production also increases within the digestive system which may make it difficult to absorb needed nutrients.
- The increased levels of estrogens in the milk (due to being milked during pregnancy) may upset our own hormonal balance. Now, there are some that say the chemical structure of cow estrogen is different from our own, and this is true. It can’t work in our bodies the way our estrogen does, but does it confuse the body? “The People” on the other side say that it does.
- Non-organic dairy comes from cows eating feed that may contain pesticide residue. Any toxins that leave the body through milk do so in the fat, so full-fat milk products may contain pesticides and herbicides which are known endocrine disruptors.
- If a person is intolerant to dairy it’s very possible that it’s causing inflammation in the body, which is bad news when you’re trying to get pregnant!
So – is milk good for fertility?
Should we be drinking milk when trying to conceive?
There is no perfect answer here, and it’s going to need to be based on your body and your situation. The best way to see how your body reacts to dairy is to cut it out completely (even butter) for one month and then add it back in for a few days to see if you feel any changes.
If you find that dairy doesn’t seem to bother you, let’s try to find the most nutritious milk we can! Your best bet is going to be to look for milk that is either fresh or low-heat pasteurized in order to preserve enzymes and nutrients. (“raw”/fresh milk can be done safely, do your research and interview your farmer!) Also look for dairy products sourced from grass-fed and organic-fed cows, preferably those that carry the A1 protein gene. You could even try switching to goat milk for a while.
My thought is that for many of us, milk can be a beneficial part of a fertility diet, but choosing the right kind of dairy can also make all the difference.