Dairy For PCOS: Should You Avoid It?
Dairy products like milk, cheese and yogurt, are a staple in many people's diets. But can these foods we love so much be making our PCOS worse?
Dairy and PCOS is a popular topic in the community. Many women want to know if avoiding dairy is necessary for hormonal balance and reversing PCOS.
I frequently get asked, “Is Dairy Bad for PCOS?”
In this post, you will find if you should avoid dairy for your PCOS. We will look at the benefits and drawbacks of dairy for PCOS and if dairy is healthy for women with PCOS.
So, if you want to know if you can continue enjoying your delicious cheese or yogurt, keep reading!
Is Dairy Bad for PCOS?
Dairy does not have to be avoided if you have PCOS. Contrary to what you may have heard about dairy for PCOS, it isn’t bad. But I understand why some women stop eating dairy. They hear milk is harmful and that they need to avoid it to balance their hormones and reverse their PCOS.
But, not all dairy is created equally. Meaning some forms of milk may be worse for humans than others. Dairy contains protein, vitamins and minerals that can help hormonal balance. So, dairy is another food that you can include in your PCOS diet.
What is Dairy?
Dairy products are a type of food made from or containing the milk from animals. Cattle like cows, goats and sheep primarily produce milk.
Dairy products are consumed by people worldwide. Except for certain regions like most of East and Southeast Asia and parts of central Africa. They include foods like butter, cheese and yogurt.
Should PCOS Women Avoid Dairy?
So, as I mentioned, many women are curious to know about dairy and PCOS.
Here's the thing.
Dairy is a very controversial topic. While exploring this topic, I too found myself feeling overwhelmed with the conflicting information.
Opinions are divided as to whether dairy is good or bad for PCOS. But there appears to be a view that dairy is bad and should be avoided by women with PCOS.
However, the research into how dairy affects PCOS is limited. One of the most referred to studies is and 8-week study in which PCOS women followed a low-starch/low-dairy diet showed improvements. But it was only done on 24 women. There also was no control group to compare the results to. So, we cannot say with certainty that the changes were because the women ate less starch or dairy.
Because of the lack of research and the controversial nature of this topic, this article will strictly be an evidence-based guide. I will simply be identifying what the science shows.
The Benefits of Dairy for PCOS
Great Source of Calcium
Calcium is the most abundant mineral in the body. It accounts for about 2% of an adult’s body weight. The adult human skeleton contains 1200g of calcium. The majority (99%) of the body's calcium is found in the bones and teeth. The remaining 1% is present in soft tissues (e.g. muscles and nerves) and bodily fluids.
Calcium is not only an essential mineral needed to build strong bones and teeth. It is also needed to carry out bodily functions including muscle contraction and controlling heart rate.
How does Calcium help PCOS?
Around 70% of women with PCOS suffer from insulin resistance. This is a condition where the cells in the body have difficulty absorbing glucose in the blood and this leads to a build-up of sugar in the bloodstream.
Research shows insulin resistance is associated with low levels of vitamin D and an increase in parathyroid hormone (PTH) levels.
Parathyroid hormone is released by the parathyroid glands (four small pea-sized glands located behind the thyroid in the neck) and its role in the body is to control calcium levels.
High PTH levels cause our bones to release calcium into the blood. The constant loss of calcium from bones increases the risk of osteoporosis.
Dairy products are a great source of calcium. A 240ml glass of whole milk contains, 28% of Calcium (% RDA). The Reference Daily Intake (RDI) is 1,000 mg per day for adults.
Adequate amounts of vitamin D is needed for the absorption of calcium and milk contains 24% of vitamin D (% RDA)
Milks large amounts of calcium and vitamin D levels may, therefore, keep PTH levels low. This may, as a result, protect your bones from osteoporosis.
Calcium found in Milk is more Absorbable by the Body
Researchers indicate the calcium found in dairy products is more bio-available and absorbable.
Experts suggest the bio-availability of calcium from milk and milk products is in the region of 30% compared to 5% from spinach, for example. Some plant foods contain oxalic acid, phytic acid and uronic acid which inhibit the absorption of calcium. As a result, they are not considered bioavailable sources of calcium.
But the bioavailability of calcium from certain plant foods like broccoli is good. You can check out this list of foods that have the most absorbable calcium.
Protein found in animals are ‘complete sources of protein’. Meaning they contain adequate amounts of all essential amino acids. There are 20 amino acids in total, 9 of which the body cannot produce on its own so it must intake it through food. A food is considered a complete protein if it contains these 9 essential amino acids.
Additionally, milk contains two specific proteins, casein and whey.
- Casein- makes up about 80% of the protein found in milk. Casein is a slow-digesting protein, meaning it releases amino acids slowly.
- Whey- This protein makes up around 20% of milks protein.
Whey protein appears to be more bio-available in the body. This may be because casein is slow digesting.
Protein Helps to Balance Blood Sugar Levels
As discussed above, many women with PCOS suffer from insulin resistance. A key part of treating insulin resistance is balancing blood sugar levels and protein-rich foods help.
Researchers looked at the impact a high protein diet would have on blood sugar levels in individuals with Type 2 Diabetes.
The high protein diet group consisted of 30% protein, 40% carbohydrates and 30% fat. While the control diet consisted of 55% carbohydrates, 15% protein and 30% fat.
Results from the study show a high protein diet lowers blood sugar levels in individuals with Type 2 Diabetes. So, eating foods that are high in protein like dairy products can help manage blood sugar levels. This, as a result, can improve insulin resistance and PCOS symptoms.
Dairy is a Source of Vitamin A
Vitamin A is a fat-soluble vitamin and an antioxidant. We need antioxidants because they protect the body’s cells and tissues from damage.
How exactly does vitamin A help PCOS?
Most women with PCOS have high levels of inflammation in the body. Many factors can cause it including insulin resistance and high cortisol.
But, researchers have found vitamin A can lower inflammation. As well as improve inflammatory conditions including acne and some forms of cancers.
This is encouraging for women with PCOS who must work on lowering levels of inflammation to reverse their PCOS.
Dairy is a Source of Vitamin K
Vitamin K is also a fat-soluble vitamin. The body needs vitamin K for various reasons including binding calcium in bones to prevent bone loss and blood clotting to prevent excessive bleeding caused by an injury.
Researchers found vitamin K increased insulin sensitivity. It does this by improving insulin resistance by lowering inflammation. Inflammation can inhibit insulin signaling and eventually cause insulin resistance.
Risks of Consuming Dairy
Whilst there are great benefits to dairy for PCOS. There are some risks you must know if you are trying to balance your hormones and reverse PCOS.
Dairy’s Impact on Fertility
PCOS is one of the leading causes of infertility in women. You may have come across articles warning you against consuming dairy for fertility. But, despite the many studies, there is no conclusive evidence as of yet. But let's have a look at what the research suggests.
What the research says
A study found that a high intake of low-fat dairy products may lead to an increased risk of anovulatory infertility. Anovulation is where the ovaries do not release an egg and so ovulation does not take place. A lack of ovulation is a common cause of infertility.
The study, however, found that the women who consumed more high-fat dairy foods were more likely to ovulate and conceive.
Need for Further Research
As you can see, the research examining the impact of dairy on fertility isn't conclusive. This is because there are other lifestyle that could affect fertility. It may be that eating dairy in addition to another lifestyle choice can affect fertility. There is a need for further research to identify if dairy really is the culprit here or not.
Dairy Causes Inflammation
Above I mentioned a protein called casein. You see there are two types of casein, A1 and A2.
A study found A1 casein increases inflammation in the digestive system.
Increased inflammation is not what women with PCOS want.
But good news, you can buy milk that does not contain A1 casein. Firstly, not all breeds of cows produce milk with A1 casein. Older breeds of cows like most Jersey, Normandes, Guernseys and Brown Swiss, most cows in Africa, Asia and southern Europe produce milk which contains A2 casein.
A further alternative to cow’s milk is goat, sheep, camel and buffalo milk which also has A2 casein.
Hormones and Antibiotics Found in Dairy
In recent years, dairy has become a controversial topic. Investigations have discovered what happens behind the closed doors of some dairy farms and this has left some consumers concerned.
There are claims cow’s milk contains hormones and antibiotics that are harmful to humans.
Now I know, hearing that can certainly put you off that glass of milk or that piece of cheese. I get it, no one wants to consume foods that contain hormones in them.
But let’s take a look at what the science says.
Estrogen Found in Milk
The majority of the milk we consume comes from pregnant cows. During pregnancy, estrogen levels in the blood are higher than normal. Such changes also cause milk to have higher estrogen levels.
The milk of pregnant cows in the third trimester can contain as much as twenty times more estrogen than milk from non-pregnant cows. Now, this may concern you because women with PCOS already have high estrogen levels. But a study explains estrogens found in cows' milk are unlikely to pose a threat to adult health.
Researchers tested whether the amount of estrogen found in the milk of pregnant cows had any effect on estrogen levels in mice.
The results indicated no changes in reproductive health or cancer risk. Even at doses 100 times higher than those found in regular milk did not cause any changes.
Changes were observed when estrogens reached 1000 times the amount found in milk. The researchers explain it would be extremely unlikely to find such concentrations in native cow milk.
So, the estrogens naturally found in cow's milk are too low to pose a risk to reproductive health or cancer development in adults. But we have to bare in mind it is a study done on mice, so results on humans may vary.
Now, estrogen is not the only hormone spreading fear among dairy consumers. The next few hormones and points may not be strictly associated with PCOS. But it is worth mentioning because no one wants to be drinking cow’s milk which contains artificial hormones.
Bovine Growth Hormone (bGH)
Bovine growth hormone (bGH) is made from protein and is produced by the cow’s pituitary gland (a region in the brain). Cow’s produce this hormone in small quantities to help a young calf grow.
A man-made version of bGH (which is FDA approved) was created to increase the production of milk from cows.
Research indicates bGH is not biologically active in humans. Meaning growth hormones from cows have no effect on our own hormone receptors.
The use of man-made bovine growth hormone (bGH) has been banned in the EU, Canada and Japan. But is still permitted in the United States.
Antibiotics found in Cow’s Milk
But with that said. Increasing levels of this hormone, to boost milk production, puts lots of stress on the cow’s udder. This extra stress can cause bacterial infections and problems with the milk.
Cows may become more susceptible to udder infections called mastitis. Mastitis is a condition where the udder tissue becomes inflamed. Inflammation usually occurs as an immune response to bacterial infection. This condition can lead to the creation of pus which can end up in the milk. So farmers use antibiotics to treat it. These antibiotics can then, as a result, end up in the milk we consume. But farmers are supposed to discard the treated cow’s milk for several days until the antibiotic residue disappears.
Before milk reaches our shelves, shipments are tested for antibiotics. Milk shipments that test positive are rejected and action is taken against the farm.
But unfortunately, the FDA reported that some farmers are slipping through the checks. This is because they are using antibiotics that are not routinely tested because they are illegal.
The use of bGH is thought to increase the production of Insulin-Like Growth Factor-1 (IGF-1).
IGF-1 is also a hormone made from protein and is produced by the liver in response to the bGH by the pituitary gland. Its main role is to stimulate proper growth: bone and muscle.
Studies show IGF-1 in cows is identical to human IGF-1. But also the amount of IGF-1 found in cow’s milk is within the normal range found in human breast milk.
Now as humans, we want to promote growth of bones and muscles but we do not want to stimulate the growth of cancer cells. Some evidence indicates a link between high IGF-1 levels in the blood and an increased risk of cancer. But correlation does not equal causation. We cannot say with certainty that higher IGF-1 levels promote cancer or if it is something else. Further research must be done.
What You Can Do To Avoid These Hormones
As you can see, the research shows that the hormones found in milk have no effect on humans. But, I understand the thought of drinking milk with hormones is worrying. So, to avoid growth hormones (if you live in the US) you can look for organic milk or milk that has the ‘hormone-free’ label.
Milk labeled as organic comes from cows that have not been treated with man-made hormones or antibiotics.
Sex hormones like estrogen, however, cannot be avoided as they are naturally found in milk.
Researchers suggest that 65-75% of the world’s population is lactose intolerant. Lactose intolerance is when the body cannot break down lactose (the sugar found in milk). This is because the body does not produce enough of the digestive enzyme called lactase.
Symptoms of lactose intolerance include bloating, abdominal pain, gas, nausea and diarrhea. Research shows probiotics and yogurt enriched with beneficial bacteria can help. Experts suggest that these bacteria may even produce their own lactase enzyme. As a result helping with the breakdown of lactose and improving the symptoms of lactose intolerance.
Dairy Weakens Bones?
In the benefits section, I said dairy can help strengthen bones because it's high in calcium. But some people suggest it can weaken bones. The study which most people refer to when arguing the impact has on bone health was not scientifically valid because it was based on memory.
Should Women With PCOS Avoid Dairy?
The truth is, there is no clear yes or no answer. Dairy products are a great source of calcium and vitamin D which can strengthen your bones. They also contain vitamin A which can help lower levels of inflammation in the body. Dairy is also a good source of vitamin K and high-quality protein which can help improve insulin resistance.
However, the jury is still out on whether dairy is healthy and safe for women with PCOS. Firstly because there is not enough research looking at the impact of dairy on PCOS. Secondly, there are tons of conflicting results and information among researchers. Studies provide evidence for and against dairy consumption for humans. But correlation does not equal causation. Meaning we cannot with certainty that dairy causes the risks mentioned above, or if it is something else. So there is no straightforward answer.
Ultimately, the decision of whether you should avoid dairy depends on your individual tolerance to milk and your ethical beliefs. It is perfectly fine to want to avoid dairy because you think the production of milk is unethical.
The arguments against dairy were enough to convince me to cut it out of my diet. So, I understand how you must be feeling.
To help you make a decision, I suggest you use scientific evidence and the signs your body is giving you.
From the evidence, it can be seen that not all dairy is created equally. Choosing organic milk or milk from older breeds of cows like Jersey and Normades, or milk from goat and sheep may be a healthy and safe option for PCOS and human consumption. But the ideal amount of dairy to consume is still not clear.
Do I Consume Dairy?
Personally, I am not the biggest fan of dairy. So if I do not eat any it does not really bother me. But I do not go out of my way to avoid it. In moderation I do enjoy eating some Greek yogurt and halloumi.
When it comes to milk, I choose organic or goats. But I also enjoy plant-based milk’s like cashew, coconut, hazelnut and oat.
Just like with most things, it is all about moderation. Eat a well-balanced diet that includes green leafy vegetables, beans and nuts so you get the nutrients you need. This way you don't have to rely too much on dairy.
Hey there! I am Despina Pavlou, founder of PCOS Oracle, certified personal trainer and corrective exercise specialist. I want to share with you the diet and lifestyle changes I made to naturally reverse my PCOS and achieve hormonal balance. I believe using my holistic approach you too can take back control from PCOS.