What are phytoestrogens and how can we limit them in our food sources?

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December 4, 2025

Phytoestrogens mess with the estrogen hormone in your body.

Phytoestrogens are natural chemicals found in plants that act somewhat like the estrogen hormone your body makes. They're in foods like soybeans, flaxseeds, whole grains, and various fruits and vegetables.

Because their shape is similar to human estrogen, they can attach to the same spots in your body that estrogen does. Sometimes they work like estrogen (giving you similar effects), and sometimes they actually block estrogen from working.

Think of it like having a key that's similar to but not exactly the same as your house key, sometimes it can unlock the door, and sometimes it just gets stuck in the lock and keeps other keys from working.

When you have an overload of phytoestrogens, it can have a negative effect on your health and wellbeing.

Phytoestrogens may alter hormonal balance, impacting menstrual cycles, fertility, and reproductive development. They mess with hormone production by interfering with the enzymes your body uses to make hormones.

You intake phytoestrogens in many ways, but the most significant is probably your food.

You're exposed to phytoestrogens through several everyday products. Anti-aging beauty products often contain plant extracts rich in these compounds, marketed for their potential skin-rejuvenating properties. Some cleaning products also include plant-based ingredients that contain phytoestrogens. Additionally, many dietary supplements, particularly those aimed at menopausal symptom relief or general wellness, deliberately include concentrated phytoestrogens.

When animals eat foods that are high in estrogen, that transfers to the foods they produce.

When animals eat soy, the plant estrogens can interfere with their hormones. The effects depend on the animal type, how much they eat, and their gut bacteria. And while it does not only affect the animal, they can transfer into the milk, meat, and eggs you eat, potentially impacting your hormone balance.

Phytoestrogens are worst in eggs and dairy.

Dairy Cows and Milk

Feeding soy to dairy cows can increase phytoestrogen levels in their milk. Soy contains compounds called isoflavones, which are a type of phytoestrogen. When dairy cows consume soy based feed, these compounds can be transferred into their milk, though the concentration varies based on the amount of soy in the diet and other factors.

For farms committed to producing the cleanest possible dairy products, avoiding soy in cattle feed is worth considering, which is just one of the reasons why we feed 100% grass all year long.

Beef Cattle

With beef cattle, the situation is somewhat different. While phytoestrogens from soy feed can be present in the animals' system, the concentration in muscle tissue (the meat we eat) is generally much lower than what you'd find in milk or eggs. However, for those looking to minimize phytoestrogen exposure across the board, a soy-free diet for beef cattle makes sense. Again, 100% grass fed and finished is the way!

This is why Miller's Bio Farms chooses to NOT include soy or flaxseed in its laying hen and cattle feeds.

Flax and soy are common ingredients in conventional chicken feed, which is one reason why our chicken feed has neither. Here's what makes this especially concerning with chickens eating flax or soy: when a hen eats phytoestrogens, they pass directly into the egg yolks. What the chicken eats ends up on your breakfast plate.

This makes Miller's honest eggs LOW in phytoestrogens.

By eliminating the soy and flaxseed, our eggs now contain significantly less phytoestrogens than conventionally produced eggs. This means a cleaner, more natural product for our customers.

Making people healthier (not sicker) matters a lot to us, and overconsumption of phytoestrogen is a major concern.

For Adults

Reproductive Health: High amounts of phytoestrogens can interfere with your menstrual cycle and fertility. There was a case report of three women who had abnormal bleeding and fertility problems that went away when they stopped eating so much soy.

Hormone Disruption: Soy can suppress your natural hormone levels and interfere with ovulation in women trying to get pregnant.

Behavior Changes: Animal studies show phytoestrogens can affect sexual behavior, anxiety, and aggression, though we don't know if this happens in humans.

For Babies and Children

This is where scientists are most worried:

Developmental Effects: Your brain and reproductive system develop during specific "critical windows" when they're especially vulnerable to hormones. If phytoestrogens interfere during these times, the effects could be permanent.

Soy Formula Concerns:

Babies on soy formula have blood levels of phytoestrogens that are 1,000 times higher than their natural estrogen levels
Female babies on soy formula show signs of estrogen effects (like changes in vaginal tissue) that breastfed babies don't
One study found that girls fed soy formula as babies were more likely to develop breast tissue early (around age 2)

Animal Studies Show Problems:

Early puberty
Irregular reproductive cycles
Fertility problems
Abnormal development of ovaries and uterus
Changes in brain structure that control reproduction

The biggest problem is that we're conducting a giant, uncontrolled experiment. Soy is now in 60% of processed foods, millions of babies are raised on soy formula, and we won't know the full effects for decades.

The bottom line is that more research is needed. But, now that you know, you can be conscious about your phytoestrogen intake.

More research is desperately needed, especially long-term studies following children exposed to high levels of phytoestrogens as babies. Until we know more, parents should think carefully before choosing soy formula unless their baby has a true milk allergy, and everyone should be aware that "natural" doesn't automatically mean "safe", especially in large amounts.

Until then know your farmer, know your food!

Be proactive in asking questions on your food sources, how the animals live and what they eat, be your own advocate! Look for flax free and soy free items whenever you can, read labels, eat whole foods.😊

Check out our flaxseed free, soy free, and low phytoestrogen eggs!

References:

https://www.pnas.org/doi/10.10...
https://pmc.ncbi.nlm.nih.gov/a...
https://holplus.co/phytoestrog...
https://rep.bioscientifica.com...

Eggs

Do probiotic cultures withstand freezing? Should you freeze your beloved dairy?

Multiple people were surprised that I did NOT recommend freezing yogurt and kefir. Their anecdotal stories told a different tale, one where you can freeze yogurt and kefir at home with varying success. There was one BIG outstanding question from these conversations - what about microbiology? Can probiotic cultures survive freezing? I did some research.

Everything you need to know about raw dairy storage

From your first sip to storing it right, here's a friendly, no-fuss guide for curious first-timers and longtime fans alike.

How to know if you can trust your raw milk farm

*Originally published on 1/13/26, Updated on 2/01/26.* I know how hard it is to find clean raw milk from a farm you can actually trust. You may have spent hours researching farms, reading reviews, asking questions in Facebook groups. Maybe you’ve even driven out to visit farms, met the farmers, looked at their operations. Or maybe you've been burned before by a farm that talked a good game but cut corners. Or maybe you're still searching for that one farm where you can feel completely confident giving their milk to your kids.So let me tell you what happened here in the last few weeks, because this story will show you exactly who we are, and more importantly, it might help you figure out what to look for in any farm you're considering trusting with your family's health. The first email It started the day after Christmas. A customer emailed in saying she wasn't feeling well after drinking our raw milk. Then, a day or two later, another email. Another customer, same story. The team got the details from them, the label color and the dates on the milk. My stomach dropped, it was my brother John's milk. Now here's what most farms would've done, and I'm being completely honest with you. They would've thought "it's only two people out of hundreds, it's January, it's flu season, the flu is spreading like wildfire right now, it's probably just that" and moved on with their day. Maybe they would've made a mental note to keep an ear out for more complaints, but that would've been it. I tried to tell myself the same thing that night. "It's probably nothing. It's flu season. These things happen." But I couldn't sleep. Because what if it wasn't nothing? What if there was even a small chance that something was wrong with our milk, and we did nothing about it? A tough decision I then contacted a DHIA to come out to test the milk. See, we'd already done our regular testing, the testing we do on every single batch that isn't even required by law. But those two emails kept replaying in my head. We needed to know for sure. We sent the milk samples to the state lab that day. Then came the hardest part, the waiting. If you've ever waited for medical test results, you know that feeling. Every hour feels like a day. You check your email or phone constantly. You play out every possible scenario in your head. And since we were now working with the state the test result didn't come back instantly, it took 2 weeks. The result that changed everything When the State inspector stopped in Thursday the 8th they confirmed the testing results."Positive for Campylobacter." We’ve been doing this a long time. Through every season, every challenge, and every batch of milk, we’ve never had a positive Campylobacter test. That’s not luck, it’s the result of how seriously we take producing clean, safe raw milk. I sat there just processing it. The inspector then let John know that we couldn't use his milk until it was clean again. What happened next Immediately we'd pulled all of John's milk from going out the door. Then I started drafting an email, one that had to be sent to over 800 trusting customers. Every single family who had purchased milk from us and possibly John's farm in the affected timeframe. Some people thanked us for being proactive and honest. Some were understandably upset, and they had every right to be. A few were scared. I told a few to call or email back if they had concerns or if anyone in their family started feeling sick. Those were some of the hardest phone calls and emails I've ever answered. But every single one of those families deserved to hear it directly from us, not from a recall notice in the mail, a news station, or a post on social media. The State gets involved The State inspector put John's farm under official quarantine on 1/8. That means no milk leaves his farm until we get two consecutive clean tests, taken at least a week apart. The farm is certified for raw milk production in PA. That's why the State got involved. *Side note: If a farm was NOT certified and is operating with a PMA (private membership) or just on the black market, none of the above would have happened. What's going on with the state of our raw milk right now? If you're a current customer reading this, here's what you need to know: Your milk is safe.Look at the bottles in your fridge right now. See those colored "best by" stickers? Blue, orange, and green? That's our farm identification system. We implemented this color-coding years ago as an extra safety measure, a way to quickly trace every bottle back to its source farm. At the time, it seemed like overkill. Now I'm incredibly grateful we did it, because that system is exactly what allowed us to identify which specific farm the issue came from within hours and protect everyone else. Right now, you're only receiving milk from our three other farms: Ben’s farm, David’s farm, and Daniel’s farm. All three have tested completely clean. All three are operating under the exact same safety standards they always have. All three continue to be inspected regularly by the state and tested by us with every single batch.If you see blue, green, or orange stickers on your milk, you're good. If you happen to have bottles with different colored stickers and you're concerned, please give us a call or send us an email. But based on our testing timeline and distribution records, the affected milk has already been consumed or disposed of. Our testing standards and why they matter to us Let me pull back the curtain and show you exactly what goes into keeping your milk safe, both what the law requires and what we do beyond that. What Pennsylvania Law Requires:The State of Pennsylvania doesn't mess around with raw milk safety. And honestly, we're glad they don't. Here's what they require to have a raw milk permit: Our milk is tested for general bacteria counts twice per month at state-certified laboratories.Our farms are physically inspected every three months specifically for raw milk production safety standards.Our cows are tested twice per year for pathogens at state-certified labs.We undergo standard dairy inspections twice per year (these are separate from the raw milk inspections).**These aren't suggestions. These are legal requirements, and farms that don't meet them lose their raw milk licenses. What we do beyond these requirements: Here's where we go further than the law requires, and this is important: We test every single batch of our milk, on-site, before it goes out to customers.YES. Every. Single. Batch.We test for:TCC (Total Coliform Count) - this tells us about general sanitary conditionsSPC (Standard Plate Count) - this tells us the overall bacteria levels The state doesn't require this batch-by-batch testing. Most raw milk farms don't do it because the testing equipment is expensive and it takes time and expertise. We do it anyway because when you're trusting us with your family's health, "meeting the minimum requirements" isn't good enough for us. We also have super meticulous cleaning standards. After we started testing every batch, we were able to see how much cleaning affects milk quality. For this reason, our barns and milking parlors are much cleaner than the average barn. We have the data to know it matters... a lot. Plus we have extra hot water for cleaning. We know that matters, too. Check out our milk safety here. The real question is who can you trust in the raw milk game? Here's what I've learned about trust in the raw milk world: Any farm can talk about their safety standards when everything's going smoothly. Any farm can show you their clean barns and happy cows and tell you all the right things when you visit. But… you truly know who a farm really is by what they do when something goes wrong. Think about it. We could've ignored those two phone calls and convinced ourselves it was just the flu. We could've done the bare minimum, waited for the state's regular testing to maybe catch it, or maybe not. We could've quietly stopped using John's milk without telling anyone why. We could've sent out a vague email about "an abundance of caution" without admitting what actually happened. Instead, we: Took those two complaints seriously immediately, even when it would've been easier to dismiss them.Ordered extra testing on our own dime without being required to.Shut down production with John’s milk the moment we got a positive result.Emailed every potentially affected customer.Voluntarily reported to the state before they found it themselves. Are being completely transparent with you right now, even though it's embarrassing and painful and might make customers lose trust and go somewhere else.I'm not telling you this to pat ourselves on the back. I'm telling you this because this is what you should demand from any farm you're considering. Not perfection, no farm can guarantee perfection, and any farm that claims they can is lying. But you deserve a farm that will tell you the truth and do the right thing when problems happen. Questions you should ask ANY raw dairy farm:If you're shopping around for a raw milk source, here are the questions you should be asking:"Do you do any testing beyond what the state requires?"If they say no, that's not necessarily a dealbreaker. Plenty of farms only do state-required testing and produce perfectly safe milk. But if they say yes, ask them to explain exactly what they test for and how often. Farms that go the extra mile will be proud to tell you about it in detail."Can I see your most recent state inspection report?"By law, these are public records. A good farm will show you without hesitation. If they dodge this question or get defensive, walk away."How do you track which farm or batch milk comes from?"If they have multiple farms or multiple days of production, they need a tracking system. Our colored stickers might seem simple, but that simple system saved us in this situation. If they can't tell you how they'd trace a problem back to its source, that's a problem."Have you ever had to recall or stop production? What happened?"I wish I could tell you we've never had issues, but that would be dishonest. We had an issue a few years ago with RB51, a child was hospitalized from it. It was caused by the VACCINE strain of brucellosis. This is why we no longer allow cows in our herds who have been vaccinated for brucellosis. What matters is how farms handle those situations. When it comes to food, it's not a matter of IF but WHEN with food safety. According to the CDC 1.5 million people are become ill from Campylobacter on a yearly basis. Most of these cases come from raw or undercooked poultry or raw poultry juices. So where do we go from here? Well, John's farm is under quarantine until we get two consecutive clean tests. The first round of retesting was Thursday the 8th and the results came back negative on 1/14. And then there's another test that was taken Monday 1/12 and the results from that test was also negative. He's checking the milking equipment, the cleaning protocols, the cow health, the water sources, everything. We're not cutting corners. We're not rushing this. We're doing it right, even if it takes months. In the meantime, your orders will keep coming from our three other farms. Same quality, same safety standards, same farmers who care deeply about what they're producing. Check those blue, green and orange stickers, that's your assurance of exactly where your milk is coming from. We're also reviewing our protocols across all four farms. Could we test more frequently? Should we upgrade equipment? Are there additional safety measures we should implement? We're asking ourselves hard questions and we're willing to invest whatever it takes to prevent this from happening again.Why are we telling you all of this? I debated whether to write this post. Part of me wanted to handle this quietly, just contact the affected customers and move on. It would be easier. Less risky. Less embarrassing. But that's not who we are, and more importantly, that's not what you deserve. You deserve to know. You deserve to know everything about your food, in good times and in bad. We're heartbroken this happened. Truly. But we're also rolling up our sleeves and doing everything right. We hope that we can earn back your trust. Because at the end of the day, trust isn't built by being perfect, it's built by being honest, being thorough, and doing the right thing even when it's hard.I know you probably have questions. Here are the most common ones we have been getting:Q: Should I be worried about the milk I already drank?A: If you drank milk from John's farm in the affected timeframe and you're feeling fine, you're almost certainly fine. The milk, whether in glass or plastic, would have had a white label on it with a date between 1/16-1/22. Plus, we directly emailed anyone who could have gotten that milk… so you would know.Q: How do I know if I’m sick because of Campylobacter?A. Campylobacter symptoms typically appear within 2-5 days. And symptoms can last up to 7 days. If you do develop symptoms (diarrhea, cramping, fever), hydrate, rest and nourish your body with bone broth, sourdough toast, bland foods (like a BRAT diet - bananas, rice, apples, and toast). Most cases resolve on their own.Q: How did this happen if you test every batch?A: That's exactly why we're investigating John’s cleaning protocols and farming standards. We're reviewing the timing of tests, storage protocols, everything. Once we know, we'll implement changes to help prevent something like this from happening again.Q: Will you use John’s farm’s milk in the future?A: If the milk is clean and the problem is resolved, yes we will. We will require two consecutive clean tests at least a week apart. And, we’ll need to identify and address the root cause. We won't rush this. Safety first, always.Q: Are you changing your safety protocols?A: We're reviewing everything right now. If we identify improvements we can make, we'll make them immediately across all farms. You can view our milk safety and protocols here: https://millersbiofarm.com/mil... The bottom lineWe believe raw milk should come from a place where questions are welcomed, testing is routine, and honesty isn’t conditional. We believe in the benefits of raw milk and all its wonderful properties. Raw milk is honestly incredible for your body when you think about what's actually in it. It's a complete, living food packed with natural enzymes, vitamins, healthy fatty acids, and powerful immune-boosting compounds like immunoglobulins that work with your body exactly as nature intended. Raw milk keeps all those beneficial bacteria that are amazing for your digestion and gut health. You're getting natural antimicrobials and probiotics that actively support your immune system and help your body thrive. It's basically the difference between drinking something truly alive and nourishing versus something that's been processed into a pale imitation of real milk. When you drink raw milk, you're getting all the goodness that's meant to be there, nothing destroyed, nothing missing, just pure nutrition the way it was designed to fuel and protect your body. *UPDATE 2/01/26 John's herd has now had 2 negatives and the milk is safe to use again so we are integrating his milk back into our production again. I'd love to hear from you. Comment below to share your thoughts with our community (no account required). Or, contact us to keep it private 😊 References: https://www.cdc.gov/campylobac...