Dairy products like milk, cheese and yoghurt have received a particularly bad reputation in recent years for being bad for both our general health and our hormones. As a result, the rise of dairy-free alternatives has caused plant milks to now take up an unprecidented 10% of the global milk market, and these numbers are rising every year.
But what is the truth about dairy? Is it really the health demon it has been made out to be, and can it truly be bad for our hormones?
A quick google search will show you that the dairy debate revolves around four key health markers that can all affect human hormonal function: inflammation, ingestion of artificial growth hormones and antibiotic reside, alongside magnesium depletion. Let’s explore each in detail.
- Is Dairy Inflammatory?
Chronic inflammation affects our hormones in many ways. It can impact our thyroid hormone (responsible for metabolism), boost cortisol (our stress hormone) and cause estrogen and testosterone imbalances. It is even thought that over time, chronic low grade inflammation can lead to autoimmune and hormonal diseases. As a result, breaking down dairy’s potentially inflammatory properties is key to understanding its impact on our hormones.
Inflammation is actually part of the body’s attempt to heal. It’s the first step of the process in which your immune system notices an irritant and attempts to remove it. Inflammation can be described as either acute (temporary symptoms that appear suddenly) or chronic (long lasting). It can take many forms including swelling of different parts of the body, pain, loss of function, a feeling of heat and more. Many health conditions involve some form of inflammation including enteritis, cystitis, rheumatoid arthritis and bronchitis (look for illnesses ending in – is).
Dairy products contain a variety of nutrients including calcium, protein, vitamin D and more. When we break these down, there are three key ingredients that could potentially be inflammatory based on the research:
- Lactose (milk sugar)
- Casein (the main protein present in milk) and whey proteins
- Saturated fats
Lactose may cause inflammation in that many people are lactose intolerant in that their body naturally lacks the key enzyme that breaks down milk sugar in the body. Others may not be lactose intolerant, but to their individual health circumstances mean they are not digesting lactose properly. This can lead to bacterial fermentation in the gut that leads to inflammation.
For others, the proteins found in dairy products can cause allergic reactions and be difficult to digest. They may also react with other proteins in the body when digested, triggering an immune response. Some studies suggest that casein might increase intestinal permeability in sensitive individuals, again leading to inflammation.
Lastly, the saturated fats present in dairy products have been shown to activate inflammatory pathways in cells, lead to lipid accumulation in tissues and contribute to insulin resistance, which we’ll know from previous posts is deeply linked to hormonal conditions like PCOS.
So whilst yes, there are certainly nutrients present in dairy products that can cause inflammation, it’s important to note that there is no universal rule. Each individual has their own unique genetic makeup, gut microbiome, allergies and sensitivities that result in varying degrees of inflammation around certain ingredients. Limiting dairy intake can certainly play a part in reducing inflammation, therefore decreasing its potential to negatively impact hormonal levels.
2. Do Artificial Growth Hormones Play a Part?
Depending on where you live in the world, consuming dairy may expose you to recombinant bovine growth hormone (rBGH), also known as recombinant bovine somatotropin (rBST). rBGH is an artificial hormone given to dairy cows to increase milk production. Whilst it is not directly added to milk or dairy products, you can be exposed to small amounts of it if a dairy cow has been treated with this hormone during the production phase.
Different countries have different policies on the use of rBGH. The European Union, Canada, Australia, New Zealand, Japan and others have banned the use of rBGH/rBST, though it is still used in the US, South Africa, Brazil, Kenya and much of the Global South. That said, growing consumer concern has meant that the use is being gradually decreased over time.
It’s important to note that all dairy products, including organic ones, contain naturally occurring hormones produced by cows as part of their normal biological processes. This means that consuming milk, cheese and other such products will always involve ingesting some form of steroid hormone like estrogen, progesterone and testosterone from cows.
Based on scientific studies and regulatory assessments, rBST is rapidly metabolized in cows and not found in significant amounts in their milk. The risk of being exposed to rBST is also thought to be reduced during the pasteurization process and human digestion.
That said, the jury is still out as to whether the hormones in dairy products are harmful to the human body, with one study finding that steroid hormones in dairy foods are a risk factor for cancer and that they can play a small part in aggravating hormone-sensitive conditions like endometriosis and PCOS.
- Does dairy contain antibiotics?
Alright, let’s address the cow in the room. Are we inadvertently chugging antibiotics with our iced lattes?
Here’s the deal:
- Many, non-organic farmers regularly use antibiotics to prevent, treat and control bacterial infections in livestock
- In many countries, it’s illegal to sell milk from cows being treated with antibiotics. Farmers have to wait until the drugs are out of the cow’s system before they can resume milk production. This period is generally understood to be 28 days.
- With that said, antibiotic reside has been found to be prevalent amongst milk samples, with one study finding that up to 37% of milk samples contain regularly used antiobiotics
- People in developing countries are more likely to be exposed to medication through consuming dairy products
So yes, whilst in most places there are control measures in place to avoid antibiotic consumption via dairy products, it is still very possible. Since antibiotics and hormones are both largely processed in the liver, regularly ingesting antibiotic reside could have an impact on estrogen and testosterone metabolism, particularly in women.
Whilst there is not much current research on the negative effect of proper antibiotic use either on public health or animal welfare, it has been shown that organic milk samples are generally undetectable for antiobiotic residue. So as always folks, go organic!
- Does dairy deplete the body’s magnesium stores?
Last but not least, let’s talk about magnesium. Magnesium is the true MVP of the minerals. It supports over 300 enzymatic reactions, which are essential for processes like energy production, protein synthesis, and muscle and nerve function. Magnesium plays a particularly key role when it comes to your hormones, by maintaining the function of the endocrine system, including the glands that produce hormones such as insulin, cortisol, and thyroid hormones.
It’s therefore of profound importance than we maintain optimal magnesium levels as part of our daily diet and supplement intake when trying to manage our hormones.
Dairy is a relatively low magnesium food item that contains high levels of calcium. Excess calcium consumption can impact magnesium balance in the body because calcium and magnesium compete for absorption in the intestines. An excessive intake of calcium may inhibit magnesium absorption, potentially leading to magnesium deficiency if dietary intake is insufficient. It’s therefore important to maintain a balanced ratio of calcium to magnesium to ensure both minerals are adequately absorbed and utilized.
A high dairy intake can also lead to an imbalance if it inadvertently replaces other magnesium-rich food sources in the diet (which tend to be plant-based) such as spinach, almonds, peanuts, cashews, avocado and tofu.
So whilst the dairy products aren’t directly stealing up all your magnesium, they can, in excess, impact both magnesium absorption and the amount of magnesium you consume as part of your daily good intake.
Got Milk? The Conclusion
Personally as someone with endometriosis, I don’t eat dairy for all of the reasons above, alongside the animal welfare concerns that come with Big Dairy. For me, maintaining healthy nutrient levels and reducing my exposure to potentially harmful chemicals is more important than the occasional mac and cheese. This is a personal health choice, and you may be different.
Processing methods, amount of dairy consumed and individual sensitivity do play a huge part in how much of a hormonal impact milk, yoghurt, cheese and other such products can have. As always, the key to everything in life is balance, and consuming small levels of dairy in moderation will likely not move the needle in terms of your overall health.
With that said, choosing organic products (or at the bare minimum rBGH-free labels) has been proven to reduce exposure to potential endocrine disruptors. So as always go organic, choose small businesses and make the decisions that work best for your body.
