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Soy Formula

ISO: Soy-Free Baby Formulas

By Amalah


I absolutely love reading all your columns. They make me happy. When I realized that I was letting myself slide, exclusively wearing yoga pants after my babies were born, you and Laura Bennett inspired me to not let myself go.

However, my question is about babies. My son is almost six months old now (wow, the time goes fast). Ever since I went back to work, I’ve had to supplement my milk supply with formula. I’m OK with using formula, since I’m not as neurotic as I was with my first child. I’ve also started to read The Unhealthy Truth, and it’s been an eye opener. My problem is soy in baby formula. I can’t seem to find a brand without soy in the ingredient list. Even the organic brands have soy. Currently, I’m using the Target generic brand which seems to have the same ingredients as Similac.

Please help! This is making me crazy especially since I’m having to use formula more and more as I seem to be drying up.

Nervous Nelly

Advice Smackdown ArchivesFor anyone wondering what the deal is with soy: From an environmental standpoint, the soybean industry is pretty much just as destructive (if not more) as corn. And BP. Probably combined. The single-crop farming process is destroying usable land, so hey! It’s okay! We’ll just flatten 10,000 square miles of rainforest and everything will be FINE. Here in the U.S., two-thirds of the soybean crop has been genetically engineered to withstand heavy doses of pesticides, and it’s generally a very, VERY highly-processed ingredient. Frankenfood! My favorite! From a health standpoint, soy has fallen from grace as some sort of super health food and some very scary safety concerns have been raised — particularly when it comes to infants and soy-based formulas and possible estrogenic effects and risks of future allergies and just…GAH. All sorts of terrifying crap. Some say the warnings are overblown (one critic I read once said giving a baby soy formula was like feeding them birth control pills at every feeding) and there’s no need to toss out the tofu and edamame from our diets. But just about everybody admits that more research is needed before we know for sure. In the meantime, use soy in careful, measured moderation, particularly with babies and young children.

For me, the mere presence of some soy-based oil in milk-based baby formula more than met my personal comfort level for moderation. Ezra got the occasional bottle of formula once my supply dipped to a level where I simply couldn’t pump much extra. I gave him organic formula, since that mostly removes the concerns about genetically-engineered soy or growth hormones in the cows.  (I do wish I’d known what I know now when Noah was exclusively drinking formula — I would have switched to an organic version back then, too. All I knew then was that organic formulas tended to be sweeter than regular versions so that’s not really good either OH MY GOD WE CANNOT WIN.)  I’m no fan of “corn syrup solids” either, but a lot of formulas use that too. Eh. I wasn’t feeding him straight soybeans mixed with high-fructose corn syrup or anything, so I just didn’t stress about every.little.thing. on the formula label.

But I completely understand your concern. And hey, if there’s a formula option that gives you better peace of mind than the one you’re using now? Let’s find it.

Funny thing: If you Google soy-free infant formulas, you’ll mostly find that the major brands are missing a huuuuge untapped market, because parents WANT THIS. They’re looking for it. They’re frustrated because it’s apparently available in the U.K. and parts of Europe, but not here. A lot of parents are switching to uber-expensive goat milk formulas or even making their own.

I found quite a few suggestions that parents try the hypoallergenic formulas, like Neocate or Enfamil Nutramigen — the ones for babies with severe allergies or digestive problems. But when I pulled up the ingredient lists, soy oil was still there, in pretty much the same amount (and in a couple cases, more) as the “regular” (and cheaper!) formulas. I thought I’d hit upon a winner with Baby’s Only Organic Lactose-Free Formula, which “is intended for babies who are lactose intolerant and offers an alternative to parents who wish to avoid soy protein in their baby’s diet.” Hooray! Except then I noticed the little asterisk at the end of that sentence, and the fine print at the bottom of the page: Baby’s Only Organic Lactose Free formula contains organic soybean oil and organic soy lecithin derived from organic soybean oil.


So. No. There doesn’t appear to be a widely-available commercial formula here in the U.S. that is 100% free of all soybean products. At least not yet. I don’t think that the amount of soy oils in most formulas are dangerous or going to cause significant harm or are anything to really obsess about, especially if you opt for an organic version without genetically-modified, earth-destroying ingredients. If your baby had a dairy allergy, then yeah…I’d probably be a bit more worked up on your behalf because there’s NO WAY I’d feel comfortable feeding my child soy formula full time (at least not after reading The Omnivore’s Dilemma and The Unhealthy Truth) , and I’d be clamoring for more options. (Though that’s when I’d probably order up some of that Baby’s Only Organic.)

We all want to do our very best and make the very best choices for our children. Sometimes it’s an easy switch to avoid a suspect ingredient, and sometimes it takes a little effort. Or even a lot of effort. Sometimes, though, you do need to cut your poor brain a break and admit that you’re doing the best that you can and it’s okay to just go with “good enough.” In this case, I’d say that switching to an organic formula should take care of MOST of your concerns about soy, and that’s more than good enough, in my book.

About the Author

Amy Corbett Storch


Amalah is a pseudonym of Amy Corbett Storch. She is the author of the Advice Smackdown and Bounce Back. You can follow Amy’s daily mothering adventures at Ama...

Amalah is a pseudonym of Amy Corbett Storch. She is the author of the Advice Smackdown and Bounce Back. You can follow Amy’s daily mothering adventures at Amalah. Also, it’s pronounced AIM-ah-lah.

If there is a question you would like answered on the Advice Smackdown, please submit it to

Amy also documented her second pregnancy (with Ezra) in our wildly popular Weekly Pregnancy Calendar, Zero to Forty.

Amy is mother to rising first-grader Noah, preschooler Ezra, and toddler Ike.

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  • Jen W

    June 19, 2010 at 10:53 am

    Soy Oil and Soy Lecithin evidently do no have Soy protein in them, and thus are “safe” for babies with a Soy allergy or intolerance. My twins are partially breastfed, and since I have never been able to produce enough milk for them to gain weight adequately, have been supplemented since they were about a week old and had lost nearly 20% of their birthweight. Within a few weeks one showed all the signs of a milk/soy protein allergy. A half dozen doctor visits later, we were told to put him on the Neocate and completely eliminate all dairy and soy from my diet. (no trivial task, mind you.) Neocate did the trick and stabilized him, but even with only 2-3 bottles of formula a day there was so way we wanted to be paying $40/can for that stuff. The gastroenterologist recommended re-introducing Soy formula, which he tolerated. Now he’s been on Soy formula for 4 months. It’s horrible, abhorrent smelling stuff, and the more I read about soy and babies I am riddled with guilt that I am feeding him this stuff at all. He didn’t respond well to the Nutramigen, so I feel like it is a choice between two evils: Soy destroying his future manhood or Neocate and my husband and I can’t afford to eat. I petitioned the insurance company to cover the Neocate and they declined, saying it was food and they don’t cover food. 
    We went with the Earth’s Best Organic Soy which seemed a little better but OMG! what am I doing to my little boy???
    The Lactose-free formula doesn’t solve our issue, since it is not lactose that is the problem, it is milk protein, which is present in all forms of milk, even with Lactose removed.
    Not sure what the point of all my rant is, other than to say I completely understand the desire to do what is best by my boys, and the doctors all feel like it is No. Big. Deal. and I am freaking out unnecessarily, but I wish there were better options and more information and that formula didn’t have to be some horrid chemical connection that costs a fortune and might be damaging my offspring. Only a few more months of formula and I can transition them to cow’s milk (if the one outgrows his allergy) or Soy/Rice/other-not-really-milk Milk and worry about the next big thing I am feeding them. 
    This mommy thing is HARD.

    • Kaylin

      October 29, 2014 at 9:55 pm

      That’s good to know, thank you. My son has a soy allergy like his father and his formula, any formula, makes him spit up and have bad gas, and his spit up even causes some skin irritation because of it. I’ve been at my wits end with the soy industry and things without soy are SO EXPENSIVE. INSANELY EXPENSIVE and so is goats milk, and in my area, it’s hard to come by. I could literally buy two goats and it would cost less to take care of them than it would to buy goats milk, or even formula AND they would take care of my lawn. lol.

      • Enock's

        January 24, 2015 at 1:06 pm

        My heart goes out to you!!!!!
        There is SO MUCH MONEY in the soy production market that it will take years for the true impact of these formulas to come to light.
        The way doctors treat us about the issue is reprehensible.
        I recommend going to a Lactation Consultant and see if there is ANY way you can try to re-jumpstart your natural milk production… Try teas, anything!!!

  • Amy

    June 19, 2010 at 11:05 am

    I recently attended a discussion put on by Purdue University’s Department of Agriculture about genetically modified food.

    Here’s the bio of the prof who spoke:

    He’s an expert in the field.

    I asked specifically about GM soy and RoundUp Ready crops (the ones that are resistant to pesticides) and he told me that the protein that the RoundUp interacts with is not present in humans or animals. In other words, RoundUp can’t hurt humans. The protein that it messes with is not in us. I still wouldn’t take a bath in it, but there’s nothing for it to mess with in our bodies. It’s actually one of the safest pesticides ever invented.

    He told me not to worry about GM foods.

    Granted, he was headed to a conference sponsored by Monsanto, makers of RoundUp, but BlogHer is sponsored by someone who’s related to Nestle, and that doesn’t make BlogHer anti-breastfeeding, you know?

    Everyone is biased, but I was there with my kids and I can’t imagine that he would’ve looked me right in the eye and told me that something was safe to feed them if it weren’t actually safe.

    • Tami

      June 18, 2013 at 11:55 am

      He is a liar, GMO’s are very bad for you of course he’s going to say it isn’t!! People need to research about GMO’s and what they do to your body, and yes he looked you in the eye with your kids standing right there with you and lied to you!!! Please research it, and start eating organic. 

    • Dana

      July 15, 2013 at 11:20 pm

      Round-up/ Glysophate is a herbicide, not a pesticide and while Monsanto says it’s safe, there are many, many independent scientists that disagree with recent studies point it out as an endocrine disruptor.  It’s being found regularly in human urine these day, you might not bathe in it, but you are consuming it.  BT is the pesticide that these Round Up Ready crops produce INSIDE them, so no they are not pesticide resistant, but PEST resistant because they contain the pesticide within the Corn, Soy, Canola, etc…no washing that off.  Next time  you attend a lecture at Purdue, be sure to ask who is funding it.  It is known that Monsanto contributes funding to depts at Perdue.  Did you also know that  last year Monsanto made over ONE BILLION in profits off Round-Up..the same company that had scientists swearing PCB’s and Agent Orange were safe.   Wouldn’t want to lose that funding…would they…Look up Plant Pathologist Don Huber’s (retired Purdue Professor) opinion on the subject.  Quite the opposite.  

  • Jaymee

    June 19, 2010 at 2:10 pm

    Just like high fructose corn syrup, it’s fine in moderation. It’s not going to harm you, it’s not going to make you un-healthy. Don’t fret about it. Of course you don’t want to go out and be on a strictly soy and high fructose corn syrup diet, but you also don’t want to be on a strictly organic apple diet either. I’m curious if you really know anything about farming. Have you ever seen the difference in the amount of bugs in a crop that has no pesticides on it? Ever seen how much of the crop gets destroyed? I don’t know about you, but I’d rather eat crops that have had pesticides that don’t harm you than eat crops that have been infested with bugs.

    • Tami

      June 18, 2013 at 11:52 am

      Yes it will harm you!!! They lie to you to get you to buy their products, the pesticides are in your food and in the long run do harm your body. Yes eating in moderation and I mean hardly ever, its ok but eating organic IS the best option period. You are fooling yourself if you think it ok.

    • Dana

      July 15, 2013 at 11:29 pm

      Problem is…with BT crops…pesticide is not on it, but IN it..the crops produce their own pesticides, so you are ingesting the same crop the bugs tried to ingest but unfortunately had their stomach rupture from it..however, bugs are becoming resistant to BT so farmers are having to douse corn and soy crops with traditional pesticides this year. So now you have internal and topical pesticides to deal with.  Go right ahead and ingest away…could it be just a huge coincidence that there’s been a rapid rise in leaky gut syndrome and other digestion disorders since the introduction of GM BT crops?

  • Cheri

    June 19, 2010 at 7:55 pm

    My son is lactose intolerant- when we switched from formula (soy) to cow’s milk- we discovered the problem. My son’s pediatrician outright told me NOT to give him soy milk. Period. She said it has estrogen in it, and don’t give it to boys ever . Just thought you might like to know….

  • Sarah

    June 19, 2010 at 9:28 pm

    Goats milk. Easier to digest than cow’s milk, can be bought organic, still has all the good fats. My mother takes soy suppliments for menopause, something about that sets off warning bells when I think about giving it to my 1 yr old son. That and the fact that my pediatrician acted like she’d rather give babies ANYTHING before soy….

  • Lisa M

    June 21, 2010 at 10:08 am

    @Jen W –
    You might want to try exposing the baby with the protein intolerance to milk-based formula every few weeks. My pediatrician said it would take a couple of bottles to tell if he was still sensitive, but I could always tell after one feeding if it was still a problem, until one day it wasn’t. It’s a been a couple years, but I think it was right around 5.5 months when it stopped bothering him and he was able to digest the protein. I still tried to switch between soy and milk formulas whenever he needed to supplement (soy was just being outed back then…you know, the dark ages), but at least I knew he could tolerate it at that point.
    You’re not kidding about trying to cut milk and soy from your diet. I remember standing in the grocery store almost crying because it was just so hard to find food that I could eat and wouldn’t cause a digestive problem to my already colicky baby (GERD=not fun).
    But most babies do outgrow the milk/soy protein intolerance. From what my ped said (again it’s been a while) the proteins are just to large to be broken down by immature digestive systems, but as the babies get bigger/older, their little systems catch up.

  • Natalie

    June 21, 2010 at 10:13 am

    argh I have a very laid back doctor, in fact he was my peditrician for the first 6 years of my life (where I had to have two kidney surgeries) before we moved out of state. My daughter had a terrible time with formula and ended up on alimentum (I spelled it wrong I know) then all heck broke lose when we tried to switch to regular old cows milk…after a month of trying this and that and every possible thing we could imagine and her losing 4 pounds (at 12 months!) we ended up going with silk soymilk because it was the only thing she could keep down/not immediatly cramp up — go right through her….my Dr never mentioned any issues with soy…now what? double argh

  • Bethany

    June 21, 2010 at 12:02 pm

    This is something I struggle with for myself after giving up meat (I’m not with Peta but I am an animal rights person, but no, I don’t judge people who do eat meat). It feel like we’re always readjusting our priorities and sacrificing some values for others. Nothing horribly helpful to say to the mom, but I hope that your guilt goes away. Your son will think that you’re awesome to have tried so hard for him and laugh and giggle.

    As for HFCS, I’m trying to hold my tongue on the lie of “moderation.” That sucker is almost impossible to eat in moderation given how it seems to be in Everything these days and there is some strong evidence that it screws with our feeling of satiety so while calorie wise it’s the same as sugar, chemically and effect-wise it’s not.

  • tasterspoon

    June 21, 2010 at 1:44 pm

    Ditto everyone’s Arrrgh.

    A few years ago a nutritionist came to talk to my triathlon club about the five things your should cut from your diet – the usual suspects, HFCS, etc., and then she shocked everyone by naming Soy.
    Organic? Nope. Unprocessed (edamame)? No good. This was all new to me at the time so I didn’t register all her reasons, but she felt that any amount of soy messes you up.
    Which position was supported by the Google. So I’ve since cut out most of our straight up tofu/soybean/soymilk consumption, or get organic non-GMO when we cave, but…I just don’t know. I mean, a billion people in China and Japan seem relatively healthy, right? And are managing to procreate. My husband’s been a big tofu fan for years and we got his swimmers tested and they were off the charts. I’m definitely freaked out by the Farm Bill / politicians & media controlled by Big Ag, and am now officially stressed out by my prospects for formula feeding…I guess I just need more data from neither industry-sponsored scientists NOR the conspiracy-theorist hippie set – and don’t know where to look.

  • Amy in StL

    June 21, 2010 at 4:44 pm

    Cow’s milk doesn’t have soy in it. I know some doctor’s say feeding infants that exclusively can cause problems but at six months, the baby is probably eating some solids anyway.

  • Camille

    June 21, 2010 at 5:01 pm

    Have you looked at Canadian infant formula? Canada has guidelines regarding soy in infant formula more along the lines of Europe (Health Canada has very strong recommendations that babies not be given soy unless absolutely necessary). My daughter is breastfed and I live in the US now, but it might be something to look into….depending on where you live, a quick trip to Canada may be an option. If not, ordering formula from Canada may be considerably less, or at least on par, with what you’re paying for your super-expensive formula.

    @Jaymee: soy is an estrogen mimic, and in developing infants and children it can have a significant impact on endocrine systems. Its not fine in moderation, and can be very harmful.

  • Liz

    June 21, 2010 at 10:47 pm

    Wow. This makes me so glad I’m able to exclusively breastfeed my baby! I don’t need one more thing to worry about (OMG Parabens, Phlalates, BPA, etc.!).

    I giggled a little bit when Amy said that some parents make their own formula… ahem… doing it right now! Oh, right.

  • Peyton

    June 25, 2010 at 12:01 pm

    My husband is intolerant of soy (it really messes with his digestive system), and we’ve had the hardest time buying foods without it. Basically, any store-bought bread, cracker or cookie will have it (even more expensive brands like Pepperidge Farm). We buy La Brea brand bread from Harris Teeter or make our own. Bisquick has soy. Most salad dressings have soy, and lots of jarred pasta sauces do too. Any type of pre-made refrigerated dough has soy, and I’ve even found it in pesto (which is supposed to be made from olive oil) and peanut butter!!

    My point is, in doing all of my information-gathering about soy (and my husband has a Ph.D. in botany), I’ve learned that yes, soy-based infant formula has way too much estrogen in it. It’s essentially the body-weight equivalent of giving an infant 5 birth-control pills a day. Scary stuff, no?

  • Charlie

    February 2, 2013 at 9:16 pm

    Yes it is a very sad state of affairs that we cant even get a good clean baby formula without Soy Bean by products in it  Having just finished a study on this exact topic I can tell you that research has proven it to reduce and tamper with boys testosterone levels and correct puberty functions as they grow up.  And with girls it can cause onset early puberty and faster development then normal –  My daughter has Double D these days and she didnt get it form me.  Sadly I didnt know this when she was little and I used Soy Formula.  Of course this isn’t necessarily a bad thing for girls (although she ahtes them being so big) but we dont want our boys having massive amounts of dangerous estrogeons into them when so little.  The reason why tofu, miso and the old fashioned Asian style soy is safe is because its been fermented which alters the consititution of the food and in small amounts perfectly safe.  However there is an old japanese wives tale that they fed there husbands lots of Soy if they thought they were cheating on them to reduce there libido.    My Sister just had a baby boy and I am on the look out for a Non Soy Formula which is how I found this page.  we all need to speak up and do something about this outrage.  Nestle is the biggest manufacturer of Soy products so they will always tell you its safe and they have funded the research in the past which is what gets passed on to the doctors.   and the Asian cultures only used Soy fermented never in baby formula products.  It  actually comes with huge warnings in many eurpoean countries already.  we need to speak up – as parenting is tough enough without this guilt as well.  

  • Garrett

    May 9, 2013 at 9:43 am

    Way late to the party but my wife has been having some health issues lately and we have had to switch to formula. Our LO is 6 and a half months old. We decided to go with the Costco brand formula. After comparing the ingredients, they 99% the same as Similac, the only thing left out, SOY LECITHIN. The product says that it contains milk products, but nothing about soy. Just thought I would share. It says my comment is too short, so both enfamil and similac say that they both have soy and the Kirkland Signature brand does not. Hope this helps someone who is looking for something without any soy or soy byproducts.-

  • Pat

    June 7, 2013 at 10:29 pm

    Also found this at

    Called Earth’s Best Infant formula all organic and without soy

  • Pat

    June 7, 2013 at 10:36 pm

    found another one

    Baby`s Only Organic Kosher Organic Toddler Formula Iron Fortified OU Dairy 12.7 OZ

    It is milk based You can but it at

    • Tami

      June 18, 2013 at 4:11 pm

      The Baby’s Only Kosher formula has soybean oil in it, so if your going for soy free this one does not fit the bill…I’m trying in vain to find something for my friends baby and the other one you talked about was the Earths Best and its $37.00!!! But at least it doesn’t have soy in it.

  • Tami

    June 18, 2013 at 4:14 pm

    Well crap it also says “may contain soy”!!! WTH?!!! It just burns me up why they put this in our childrens formula!! What the heck does a person do?!!!

  • Ashley

    October 17, 2013 at 7:04 pm

    I am dealing with this EXACT same issue! my daughter is 10 months old and im a first time mother, so I JUST today found out how bad soy can be for them! and shes been on soy formula for about 5 months now… since I stopped breastfeeding. Shes also Lactose intolerant… so im also trying to find a formula for her that’s lactose and soy free! its freaking impossible, and I make 10$ an hour… so im not trying to find a can that costs 40$ that ill go thru in 2 weeks. lol I cant! its just crazy how there are barely any options out there.. youd think that were the most powerful country in the world, and we can take care of others.. the UK, Canada and Europe can take care of theyre babies… but WE havnt found a way to take care of ours yet?! its ridiculous and I also wish that the makers of these formulas would wake up and realize that this is becoming a huge issue for them.

  • Rebecca

    February 13, 2014 at 6:42 pm

    I’ve had problems producing enough breastmilk since my baby was 3 months old. Did everything, oatmeal, fenugreek, nursing ALL the time, through the night, changed my diet etc. nothing worked. At five months I finally caved and started supplementing. My family has an issue with a severe dairy allergy, so when my baby started refusing formula, surviving on about 12 oz of breastmilk a day, I decided to try soy. He drank 5 ounces, and then promptly vomited it all up. I tried nutramigen and alimentum but he flatly refused to drink it. Out of desperation I decided to try and make my own goat milk formula. He drank it happily and slept for 5 hours straight that night. I was really surprised that the regular formula was bothering him because he wasn’t showing any typical dairy allergy symptoms. Then I happened to look up soy allergy. It fits him to the T. I am working with my pediatrician to make sure the goat milk formula that I am making is safe (she had never heard of it) but I was shocked that every mainstream formula has dairy and soy. How are you supposed to know which they are allergic to? I know they say that the soy oil and lecithin have the proteins processed out of them, but there have been studies testing that and they have found that there actually is trace protein in both. Sometimes more than others. It just amazes me that it hasn’t been noticed and replaced yet.

  • ange

    February 4, 2015 at 11:39 am

    Karicare goat formula. No soy =)

  • Jenna

    February 5, 2015 at 10:46 pm

    My baby is milk protein allergic, I use goat milk formula Nanny, you can order it from UK, 

  • Tonq

    May 21, 2015 at 5:00 am


  • Angela

    June 5, 2015 at 8:39 pm

    We bought Nanny Care from Europe for my granddaughter. Mom’s BP plummeted which caused BM to plummet as well. Nanny Care goat is fabulous and actually cheaper than formula in the US. You get the equivalent of 3 of the 12oz cans for roughly $28. That’s including shipping. Great stuff really 🙂

  • Sasa

    June 12, 2015 at 1:36 am

    thanks for sharing

  • grace

    September 23, 2015 at 4:47 am

    Thanks for the info… I am a mom of a g6pd child and i have a problem regarding on soya on formulated milk. Even i’m breastfeeding him, i need to find a formula that suit his need just incase i have to leave him for work.. This just answers my doubt. Thanks a lot.

  • Robert S

    November 16, 2017 at 11:21 pm

    I think you need to look at the effects of soy products on males. You’re way off base on this subject

  • Peter Coburn

    November 30, 2017 at 6:02 pm
    Soy contains phytoestrogens (plant estrogen) and should be avoided for developing male infants. Phytoestrogens caused erectile dysfunction in laboratory rats!

    Article summary: There is overwhelming evidence in animal models that phytoestrogen exposure can have significant consequences for reproductive health. The effects observed depend on the dose and route of exposure because these parameters impact the final serum level of the bioactive compound. In addition, the timing of exposure is critical in determining phenotypic effects because different tissues have species-specific windows of sensitivity to morphological and functional disruption. These sensitive windows generally begin in the early prenatal period and extend in some cases through adulthood. As more phytoestrogens are recognized or developed as therapeutic compounds, it will be important to examine carefully the effects of these chemicals on reproductive outcomes using animal models that replicate human exposure levels.

    Although the effects of phytoestrogens have been evaluated in only a small number of human studies, several of these studies are consistent with findings in animal models after taking into consideration the different developmental timing of specific tissues. Other human studies are more difficult to interpret because of inherent weaknesses in study designs involving large populations of human subjects, difficulties in quantifying phytoestrogen exposures, and an inability to fully control unknown factors in the diet or from the environment that could influence outcomes. There is a need for additional well-designed prospective human studies that limit these variables as much as possible and focus on environmentally relevant levels of phytoestrogen exposure. Despite their limitations, information gathered from the published human studies combined with the large number of animal studies already available clearly demonstrates that phytoestrogens have the ability to permanently reprogram adult tissue responses after a developmental exposure, and that these altered tissue responses are important for reproductive health. These findings should be taken into account when recommendations are made regarding dietary or therapeutic phytoestrogen intake, while keeping in mind developmentally sensitive time points.