Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
18 Apr

Should You Chew Your Child’s Food?

mommabirdBy now, you’ve probably seen the Alicia Silverstone pre-mastication video. It’s totally safe for work (maybe not for lunch, but your mileage may vary), but some viewers will find it a bit unsettling: Silverstone feeds her baby pre-chewed food directly from her mouth, just like a bird. I found it pretty fascinating and not at all upsetting. Before you recoil in disgust and/or horror, think about how people weaned babies before Magic Bullets, Vitamixes, Gerber baby food, and even mortar and pestles hit the scene. That’s right – they chewed their food for them. In a paper entitled “Premastication: the second arm of infant and young child feeding for health and survival,” Gretel Pelto speculates that pre-mastication was likely common practice among pre-agricultural groups and confirms that it continues today across every continent (PDF).

As to why this practice arose in humans but not other mammals, it’s the neoteny. Humans are born completely helpless, and remain so for several years (some would suggest “decades”). Newborn babies have no teeth and don’t even develop a decent set until about a year or later. This isn’t an issue at first, since they have access to plenty of delicious, nutritious breastmilk that goes down smooth. But because breastmilk is fairly low in iron (albeit a highly bioavailable form designed specially for infants), once kids run out of their pregnancy iron stores, they need a more reliable source of the mineral in addition to the milk. Nowadays, kids get iron-fortified rice cereal or baby vitamins or something silly like that, but before all that stuff, kids needed to eat iron-rich foods when the iron supply dwindled. What’s simpler and more effective for a hard-working hunter-gatherer who needs to feed her child some adult, iron-rich food – chopping up and crushing a strip of venison liver on a wooden plank with stone knives, or chewing it up and transferring it directly to the kid’s waiting mouth?

Okay, so there’s historical and evolutionary precedent for it, but is there any reason to chew your kid’s food today rather than whip out the food processor? Are there any extra upsides?

Free Mechanical Digestion

Since babies are rather limited in the tooth department, they can’t chew their food effectively, which is how most animals – humans included – mechanically digest their food. That’s why “baby food” is pureed; it’s a more socially acceptable (and financially lucrative) way of pre-chewing their food for them. And since the greater surface area of mechanically digested food bits exposes more of them to enzymatic action, pre-chewed food is more easily digested by babies (and adults).

Chewing your kid’s food is definitely cheaper than buying baby food, and it’s more time-efficient than making it in a blender or food processor.

Oral Enzymatic Pre-Digestion

Infants are born equipped with the enzymatic machinery to handle the simple sugars, animal fats, and animal protein in breast milk. They are not ready to digest a whole lot of other things, particularly dietary starch (which is often “baby’s first food” regardless). In humans who have it, salivary amylase predigests starch during the chewing process, initiating the conversion of starch into more easily assimilable carbohydrate derivatives like maltose (a disaccharide of two glucose units) and dextrin (a polysaccharide). Infants don’t come equipped with much salivary amylase right out of the box, so when a parent who wields the full array of salivary enzymes pre-masticates their food, the infant digests the food better. To get an idea of what kind of enzymatic digestion this pre-mastication is providing, let’s check the numbers:

In adults, salivary amylase (which predigests starch) is present in concentrations of 70-300 U/ml. Infants are born with “negligible” amounts, attain “appreciable levels” by 3 months, and reach 85% of adult salivary amylase levels by five months (PDF). Since Alicia Silverstone feeds her kid a vegan diet, presumably rich in fruits and starches, pre-mastication is a sound tactic.

There’s also lingual lipase, which breaks down long-chain triglycerides into glycerides and free fatty acids. Infants have lingual lipase at birth, but they have very little gastric (gut) lipase. Since babies absorb far less dietary fat than adults (65-80% versus more than 95%), a little extra lingual lipase activity provided by the pre-masticating parent combined with the kid’s lingual lipase could improve absorption rates. Hey, maybe that’s what’s causing infant obesity – a wave of pre-mastication sweeping the nation!

Unless you’re drooling into your Vitamix, the parent who pre-masticates may be giving her kid a digestive advantage.

Transplantation of “Good” Oral Bacteria

Over 700 species of oral bacteria have been identified from human mouths, and the oral microbiome of any given individual may house from 30 to more than 100 different species. While oral bacteria can trigger the development of dental caries and periodontal disease, it’s not all “bad.”  For example, many strains of oral bacteria taken from healthy children actually provide protection against harmful oral pathogens and are being developed as oral probiotics. Other strains have been shown to directly influence the immune response in gum tissues, as well as protect the host from oral pathogen-induced apoptosis and inflammation.

I wasn’t able to pull up any explicit references to pre-mastication as a transplantation method for “good” bacteria, but there is evidence that mouth to mouth contact between mother/father and offspring can transfer pathogenic cavity-causing bacteria to the child. If the “bad” can be transferred, why not the “good”?

Development of the Immune System

Saliva contains the very same antibodies found in breastmilk, like immunoglobulin A, immunoglobulin G, and immunoglobulin M. These help establish the budding immune system and provide passive resistance to pathogens, including bacterial infections and viral infections. There’s very little research on the impact of saliva-borne immunoglobulins on infant health, but we do know that breastmilk-borne immunoglobulins are crucial to the development of an infant’s immune system, so it seems likely that pre-mastication is also helpful (especially since both breastmilk and pre-chewed food enter a child through the same orifice).

Perhaps it’s even a way for non-breastfeeding mothers to give their child a leg up.

Are there any downsides?

Transfer of “Bad” Oral Bacteria

As I just mentioned, a parent with dental disease caused by bacteria could transfer the same bacteria to their child by pre-chewing his food. If the bacteria takes hold early enough, it could be difficult to dislodge it. The same could just as easily be said for the early transfer of good bacteria, though, so it’s impossible to say who “wins.”

It all depends on the oral health of the pre-masticator.

Transfer of Saliva-Borne Disease

Transfer of saliva-borne diseases is a possibility. Those include hepatitis G, herpes, TT-virus (which is widespread and seems pretty harmless), hepatitis B (although the hepatitises are present in low amounts in saliva), and there’s mixed evidence that pre-mastication can and has transferred HIV from caregiver to child, although that probably requires an open sore or wound in the mouth.

Again, it depends on the health of the caregiver.

Pre-mastication appears to be a valid, viable way for Ma (or Pa) to deliver food to a baby’s maw. There are some impressive potential health benefits, it might save money, and it could even bolster immunity. The potential downsides, however, must be considered. Overall, I don’t think it’s necessary for parents, and the social pariahism you’re likely to face may not be worth the trouble, but I certainly find it intriguing.

How about you, folks? Would you – or have you already – pre-chew your kid’s food?

You want comments? We got comments:

Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. Pretty interesting! My mom did this a little with my little brother, but we mostly fed him Gerber. Btw, while we are on this subject, I was wondering about Weston Price’s stance on making your own baby formula with raw milk, with added gelatin for better digestability…to me it sounded as stuff like raw milk and might be too harsh on an infant’s stomach. Do babies have a weaker digestive system (maybe less hydrochloric acid) that may prevent them from being able to consume certain foods?

    Pranay wrote on April 18th, 2012
  2. I had no idea that there was a “problem” with this. My 10 month old twins, as well as my 11 and 13 year olds when they were infants, have all eaten pre chewed food from Mommy at some point. It isn’t every meal or even everyday, but it is definitely very common and normal in our home. It’s instinct.

    Stephanie wrote on April 18th, 2012
  3. I have a similar story–the flipside. My sister-in-law from Antigua sucked the mucus out of her baby’s running nose to clear it. I had an initial feeling of yuck, but then thought about how ineffective my own efforts were with my own baby later and GENTLY tried it to help her breathe. Worked great. Better than the rubber bulb syringe thing. And she held still for me when it was my face doing it instead of some device.

    Joy Beer wrote on April 18th, 2012
    • I’ve never even thought of that before. My first reaction is “eewwwww”, but I get where you’re coming from with the wriggling!

      Off topic I know, but it might help other breastfeeding mums out there – breast milk works great to clear stuffed/runny noses. Plus they can eat it. It’s not instantaneous, but sure helped my (then 7wo) daughter breathe better when she had a cold!

      Phoenix wrote on April 21st, 2012
  4. It’s all moot when you realize that babies don’t need food until they show interest and start trying to eat it. In other words, breast milk is sufficient–that is, as long as the mother is getting sufficient nutrition. Until an infant starts reaching for your own food, I wouldn’t worry about trying to feed them mashed up or pureed food.

    I believe there is misinformation and over concern regarding when an infant should start eating. The myth, as far as I’m concerned, is that they should start on “real” food as early as 4 months, and certainly by 6 months. Usually, it is encouraged that they eat “easy to digest” crap like rice meal. Not much nutritive value there! Not to mention that parents are often found force feeding their kids, pushing spoonful after spoonful of that crap in their child’s mouth as the child spits it out or pushes it out with her tongue (I might do the same if someone was shoving food into my mouth!).

    Look into baby led weaning. When our daughter was about 5 months old she started reaching for our food. We offered her things she could handle, such as sticks of veggies (carrots, cucumber, celery, broccoli, etc.)…It was more about playing and exploring at that point. A few months in, she would bite pieces off (with no teeth). At 6 or 7 months she was eating 3/4ths of a pear with no teeth.

    Important to recognize the difference between gagging and choking too. Parents are often afraid their child might choke. But realize that gagging is 90% of the time what happens, it’s an important reflex and they actually benefit from it by learning to navigate the process. As far as the risk of choking, I suggest ALWAYS monitoring your child at that age when eating, and learn infant CPR.

    Lastly, about nursing…a reminder that the world average age for weaning is something like age 4…So many benefits (immune, emotional, nutritional) it’s sad we are culturally conditioned by early weaning and formula.

    Jeremy wrote on April 18th, 2012
  5. I chewed my babies food, the benefits were enormous. Not only for health reasons, but convenience reasons. We didn’t need a huge stash of baby food nearby. Or blend up portions of food. She could eat whatever we were eating. We could go out for dinner and she could share. I even took her camping at 6 months of age and she could share with us. Of course, I didn’t feed her hog dogs and such, but real food. Some comments and looks I got were pretty nasty, but most people just ignored it. It’s not like a bird that spits it straight into their babies mouths… I would chew it and then offer it with a spoon or fork or put it on her plate for finger food. I did not do this with my first child, but this time, it just felt so natural. (probably helped that my diet is so extremely different this time… last time I couldn’t chew up my chinese food or pizza for baby)

    AllisonK wrote on April 18th, 2012
  6. Interesting article!
    When is the right time to start this method?
    At 6months ?
    Thank you

    Cufang wrote on April 18th, 2012
  7. I did it with my baby when she was i think about 7 or 8 months old without even really thinking about it, just handed her some stuff i had chewed up slightly like steak, chicken or pork. That way i knew she wouldnt choke or have trouble with it. These days i just chop it up for her now shes got most of her teeth (13 months old now).

    Earthspirit wrote on April 18th, 2012
    • also should add my baby showed interest in “real” foods at 3 months of age pulling things off my plate and trying to jam them in her mouth it got to the point i had to lay her down in her bouncer while i ate. i didnt start her until 4 months she was more than ready according to our pediatrician and she took to the food quickly and easily. every baby is different levels some dont even show interest until 12 months old – a girl in my mothers group still had trouble with her baby and food he is 13 months old and she is working him through foods but he refused to eat and only screamed at the sight of it.

      Earthspirit wrote on April 18th, 2012
  8. I find all the hubbub quite amusing. Coming from a 3rd world Asian country, having mom pre-chew an infant’s food was the norm. This practice continues to this day but not in public because anything not politically correct risks the invitation of CPS from nosy folks who don’t understand the culture. I don’t do it because we don’t have kids but I bet you will wonder about it the next time you see an Asian mother and her infant. LoL…

    VVP wrote on April 18th, 2012
  9. I don’t agree with practice of pre-mastication even though it may have advantages and is found common among other animal species.

    There are many recipes for natural baby food and ways of preparing them to your child to compensate this practice.

    Shyamnm wrote on April 18th, 2012
    • Recipes? Who needs recipes when there are hundreds of natural foods right there ready to eat and a few chews away from feeding it straight to your baby.

      AllisonK wrote on April 18th, 2012
  10. The only thing that concerns me here is vegans like Alicia Silverstein having children at all.

    Jeanmarie wrote on April 18th, 2012
  11. I have a anthropologist friend who spends his summers living among a hunter-gatherer band in South America. He says the women carry on a peculiar tradition. They collect starchy fruits or tubers, mash them up with mortar and pestle, chew on a bit of it and then spit the contents back into rest of the pot full of mashed starch. After a few days, it’s fermented. The woman then goes about the group, sharing it with the men. I asked my friend if he’s tried it and he says he has. He says it’s not so bad when it’s being offered to him by one of the younger, more attractive women, but when an older lady offers it up, he feels a little grossed out by it.

    Back to the subject of masticating food for the kids, it could be worse. Herring gull parents swallow fish caught at sea, return to their baby chicks in the nest, and regurgitate the contents for the chicks to eat.

    Aaron Blaisdell wrote on April 18th, 2012
  12. Pre-chewing food for my kids, Elle now 23 & Atomic now 21, came as naturally as breastfeeding and holding their little hands as they learned to walk. I never thought much about it being right or wrong. No one ever told me TO do this or NOT to do this…it just happened quite naturally out of convenience. They each were breast fed between a year and two years a piece until they were anxious and curious to eat solid food. I remember Elle in a movie theatre with us around the age of two. I LOVE popcorn and she would not be quiet or satisfied to not try some too. But of course the hard kernels are dangerous for little ones so her dad and I spent most of the movie biting off the kernels and feeding little Elle the puffy parts to her great delight. But that was just one of hundreds of new tastes for her/them that passed our mouths first. Everything we ate, they would taste until they were acclimated. Fresh fruit, finely chewed meat or vegetables or anything that required more teeth than they yet had. This never seemed weird in the least bit. What did seem weird to me was the nasty goop in little jars. BTW, both my kids developed a FULL palate at a young age and stellar immune systems to boot. My daughter now jokes that she is so healthy because I let her eat dirt as a kid. Though I don’t remember it quite that way, I think she is referring to the fact that I was never a germ-a-phobe. The kids spent many summers playing naked in the mud puddles followed by a warm bath before bed. It makes me sad to know that all natural wood chips are no longer considered safe floor material for a children’s playground. Whoever decided that probably thinks that Gerber makes a better banana than God.

    Karen wrote on April 18th, 2012
  13. I tended to pre-chew food for our two children when they were little, but my ex-wife was not very keen on it. Now I know I was right all along!

    How else are they supposed to manage a big bit of meat if you don’t chew it up a bit first?

    Billp wrote on April 19th, 2012
  14. I have an 8 month old and I have been prechewing occasionally for her. It CAN gross other people out, but generally any complaints are quieted with my asking “Well, how do you think they did it back in the day?” Everyone pretty much knows that I’ve been doing everything as natural as possible from the start, so I’m already seen like the crazy hippie mom anyway. =)

    Laura wrote on April 19th, 2012
  15. Wellp, this is one step too far for me XD

    juzzie wrote on April 19th, 2012
  16. Eskimos/Inuit women certainly chewed food for infants. The down side was that it wore their teeth away over the course of time.

    Nigel wrote on April 19th, 2012
  17. my mother told me that this is what her mother did with her, chew the food first, a common practice in the early 1900′s among the poor.

    len worley, phd wrote on April 19th, 2012
  18. I don’t have any kids but I do have a cat. He gets lumps of pre-chewed food all the time and loves it. He doesn’t need it pre-chewed. It is just the chewy parts of meat that, I can’t finish, that I plop into his dish. He is quite happy with this arrangement.

    Nancy wrote on April 19th, 2012
  19. I had no idea this used to be common practice before the rise of “baby food”. Always fun to learn something new.

    Kristjan wrote on April 19th, 2012
  20. +1 for baby led weaning. I used to occasionally pre-chew a few things, but not regularly. He’s 17 months now and still probably 75% of his calories are from breast milk. He’ll go days with only eating a couple bites of solid food, some days it seems like he eats his weight in beef and eggs.

    Those of you who are icked-out may not have spent much time with toddlers…I get drooly kisses all day long, he puts his pre-chewed food in my mouth…sharing spit is an unavoidable part of parenthood!

    Susie wrote on April 19th, 2012
  21. To all the people who are grossed out: the kid is going to be eating dirt in another few months. What’s the big deal?

    BigTex wrote on April 19th, 2012
  22. I LMAO when I saw it. It didn’t bother me one bit.
    The Inuit in the far North pre chew raw seal meat/blubber for their infants. I used to pre chew some tough meat for my little ones when they were little. But not often.

    John wrote on April 19th, 2012
  23. Yeah, great way to pass on Epstein Barr Virus without knowing it to your infant, who later develops autism from it and strep. I did not realize I was an EBV carrier until it showed up on his blood test results and then I remembered I’d had mono and have autoimmune disease, and he’s unfortunatly got that as well from me. A poor choice to share a sippy cup with him or a fork. Poor boy.
    Parents, please, please think twice about doing anything like this. Our children are already born with a disadvantaged due to all the toxic chemicals in our bodies and society. Don’t introduce more potential bacterial or viral pathogens to their already weakened immune systems.

    Rm wrote on April 19th, 2012
  24. I have no problem with it. Not my cup of tea though. Thing is, we *didn’t* regularly wean our babies in the days before vitamix. In hunter gathere societies, kids breastfed until age 3+, when they were perfectly capable of eating with everyone else. My kids have mostly gone straight from exclusive breastfeeding, to increasing portions of table food, and skipped the nasty stuff in jars all together.

    mntnmom wrote on April 20th, 2012
  25. I did pre masticate when in a bind away from home. My daughter was happy to receive. When I think back on it, it seemed like the natural thing to do. Right, somehow. I wasn’t aware of grossing anyone out. Frankly, I didn’t care.

    Laurianne wrote on April 21st, 2012
  26. Reminds me of one of my favorite SNL skits:
    http://www.thescanlons.net/weblog/index.php?/weblog/the_bird_family/
    Hilarious!

    huntingtonharvey wrote on April 21st, 2012
  27. I’m more interested in the fact Alicia Silverstone’s vegan and is probably feeding her baby vegan as well. That bothers me more than the pre-mastication.

    Dana wrote on April 22nd, 2012
  28. They do this in Nigeria. Nobody bats an eye. It’s funny to me what we find “gross.” It’s all in our heads and how we were raised, yet we – as all humans do – confuse opinion with fact nearly 100% of the time.

    Julie wrote on April 23rd, 2012
  29. This is one of the most disgusting things I have ever heard!! There is NO excuse for chewing food for anyone!If for some reason a baby or any person can not chew their food then simply need to use a blender,food processer, or just mash it up with a fork. Some people are so disgusting it is appalling.

    Janet wrote on April 24th, 2012
  30. That is so inappropriate, no matter who you are. That is filthy to fully eat but not swallow your childs food and then let him eat it from your mouth. A babys immune system cannot fight things off the way an adults can. way more things can go wrong then mentioned. Anyone else who works in the med field will also know how bad this is to do.

    carli wrote on April 26th, 2012
  31. not healthy or normal. Sick

    carli wrote on April 26th, 2012
  32. I say I never thought I would do this until I had my 2nd Child. I had to start chew food because she has a high metabolism was loosing weight I was told to stop breast feed loosing weight because of suckling on breast. Who knew.. She was always hungry this little slender baby was loosing weight. She had to sit up to feed her at 2 weeks we started her bottle had large wholes in nipple. To prevent her from suckling to hard. Started eating from a spoon at three months per doctor request. Yes this baby try to snatch food of my mouth when we sat at the dinner table. She was hungry. Yes, I carried baby food grinder in her baby bag or when I travel. I went to other countries found out that it quite common for mothers to chew their baby food. Not everyone can afford baby food grinder.
    To each his own. There is no perfect manual how to feed your baby. You do the best you can to have a healthy and strong baby.

    M wrote on April 28th, 2012
  33. The dental bacteria transfer theory is a load of bull, fwiw. Mark (and anyone who is interested in healing naturally), I beg you to read “cure tooth decay” by ramiel nagel. It’s based on WAPF studies, promotes paleo/primal eating, and shows how dental caries are the result of hormonal imbalance from the SAD, NOT from bacteria and plaque, etc. Please read it :) it healed my sons teeth. They are ugly, but strong, and they will be around til he is ready for them to fall out at age 6ish. Before I started reading it, the dentist was reccomending full extraction of the front 4 and two molars on a 15 MONTH OLD. I figured trying to heal it before having to put my baby under for an invasive procedure was worth a shot. And today at 23 months, his teeth are in excellent, healthy condition.
    For those of you who don’t want to for our $30 for a hard copy, the book is $10 on kindle.

    Kristi wrote on April 29th, 2012
  34. Would I pre Chew my child’s food Mark Asks ??

    Hell no !

    zoey wrote on May 1st, 2012
  35. My sons nursed for the first year. They did not like cereal. My La-leche league teacher told me to feed them meat. So I did. I had a baby food grinder. I would have done whatever it took. Even prechewing if I had to. Our second son would eat 4 pieces of roasted chicken at 18 months for dinner. I was amazed at his appetite for meat early on.

    lynn wrote on May 1st, 2012
  36. We decided to freeze and grate grass-fed chicken liver as our now 9 year old daughter’s first food. She loved it and the pastured egg yolks! For young parents on this leg of their life journey, I recommend Nina Plank’s Real Food for Mother and Baby. (pre-mastication not required!)

    Ivana Kadija wrote on May 7th, 2012
  37. Can I just say that the risk of dental caries may not be very high because the main bacteria species implicated in initiating a carious lesion in a tooth is Streptococcus mutans. They aren’t found in mouths without teeth, and what is more, don’t colonise the mouth until aroud 18 months to 2 years, during a ‘window of infectivity’. This may be due to a tailing off or loss of protective factors in breastmilk. (I’m not sure how this stands for artificially fed infants.) Of course, there are other bacteria implicated in the carious process, but again I’m not sure how important they may be in this context.

    April Whitlock wrote on May 14th, 2012
  38. My 10-month-old was not interested in the joys of eating. I tried store-bought purees. I tried mashing up yams and rice with breast milk. I tried finger foods to give him control. He showed minimal interest. Yogurt was the only hit for weeks. We’d sneak fruits and veggies into it. But he was passionately interested in anything we ate. One night I looked at my plate – it was all great, organic, simple food. I gave him some out of my mouth without even thinking about it. It was an IMMEDIATE hit. He couldn’t get enough. In the back of my mind I wondered if it was gross, but it seemed so incredibly natural. Some genetic mom part of my brain knew what it was doing. Since that night, he has loved eating and will now feed himself. I still pre-masticate (amazing to know there’s a term for this) some things, but he’s well on his way to becoming an independent eater. Pre-chewing makes a million times more sense than using our Magic Bullet every meal. Thanks for providing some beneficial science!

    Jade wrote on August 16th, 2012
  39. I think this idea has plenty of merit. At least it’s just chewing the food, unlike wolves who throw up partly digested meat to feed their young.

    Rosalie wrote on November 12th, 2012
  40. Yes I’ve done it, when your baby’s hungry and you’re eating and there’s no way to get baby food, it’s just the logical thing to do, I don’t even think about it. I don’t do the mouth to mouth thing, I usually spit it onto a finger and put it in his mouth. Quite often baby prefers to eat off my finger than his spoon. I just go with it, it’s natural he likes the skin contact. It’t not like they do this forever, so I enjoy it while it lasts.

    Krish wrote on March 27th, 2013

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