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Side effects of soy milk for babies

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Babies have special nutritional needs as they begin development. It’s important to remember that a baby’s needs are very different than an adult’s, and that they change frequently. 

Experts recommend feeding your baby breast milk or specifically designed baby formula until they are transitioning to solid foods at between 6 to 12 months old. Experts do not recommend feeding infants with soy milk because it is not a nutritional meal replacement for breastmilk or formula. 

The best age to start introducing soy based drinks for hydration is alongside solid foods as your child will gain nutrients from a variety of sources. If your child solely drinks soy milk for a meal, they may lack macro and micronutrients, and the soy may also introduce averse effects. 

This article explores the site effects of feeding soy milk to babies. Answered below are frequently asked questions about the side effects of soy milk for babies, and how to alleviate such concerns.

Pediatricians usually don’t recommend feeding soy milk to babies under 1 year old, and then only as a beverage and not a complete meal replacement. Consult with a pediatrician or physician to determine if feeding your baby soy milk is right for your specific circumstance.

Soy Milk vs Soy Formula for Babies

There is an important difference between soy-based formula and soy milk. 

Soy baby formula is designed to contain all the nutrients that your baby needs for healthy growth and development. Soy milk does not always contain the same nutritional profile, even if it has been fortified with additional vitamins and minerals. 

Here are some additional differences:

  • Soy milk may not have the same total amount of nutrients as soy based formula. Soy milk may contain other allergens, additives or preservative that will not be in soy based formula, depending on how the soy milk itself is made.
  • Soy milk might cause stomach and intestinal side effects, including bloating, constipation, and nausea, especially when consumed in large quantities.
  • Soy milk is often sweetened with added sugars as it was made for an adult consumer. Although we love the taste of some soy milks with sweeteners, we don’t recommend consuming too much of your calories or sugars through beverages. We definitely do not recommend feeding babies or children sweetened beverages. 

It is important to differentiate between soy milk and soy formula. They are both soy based, but formula contains all the necessary nutrition for baby growth and development, while soy milk lacks the macro and micronutrients.

Soy milk is never to be used as a meal substitute, but only as a supplement to any wholesome diet. If a baby is fed soy milk in place of breastmilk or formula, they will be lacking major nutritional value.

Is soy milk bad for babies?

Soy milk doesn’t contain the full nutritional profile that babies require for growth. Feeding a baby exclusively soy milk may lead to severe vitamin, mineral, or protein deficiencies. 

Experts recommend feeding your baby breast milk or formula. They don’t recommend feeding a baby soy milk, but if you do, it is best to use soy milk as a supplement alongside other milks for hydration purposes only. 

There have been many studies showing that breast milk supports many processes in your baby and also contributes to the immune system, respiratory system, and overall health of your baby. In cases when breastfeeding is not an option, we suggest using a specifically designed baby formula. 

Can soy milk cause diarrhea in babies?

Yes, soy milk can lead to diarrhea in babies, especially those who have allergies. In fact, one of the most common food allergies that affect the digestive tract in babies is soy allergies. 

If your baby experiences diarrhea, it can be dangerous as it can result in dehydration due to excessive loss of fluids from their body. 

The main symptoms of dehydration are concentrated urine, dry mouth, and lack of tears. Increase the amount of fluids to replace any lost liquids. 

If there is a prolonged reaction, you should seek medical help for your baby. 

Food allergies are very common in the first year of your child’s life, and they are likely to outgrow food allergies, including milk and soy allergies around three years of age. If your child has allergies, it is important to be diligent with all ingredients in the foods being served to allow your child the appropriate time to acclimate [1].

Why is soy milk not good for babies?

Soy milk will not provide the full set of nutrients required for a developing baby. Experts suggest breast milk or baby formulas. 

It may be ok to feed your child fortified, unsweetened soy milk in moderation after the age of 12 months, after they have started to consume pureed foods. But soy milk should never considered to be a meal replacement for wholesome foods, but only used as a supplement to keep hydrated.

There is a chance that your baby is allergic to soy and then will also be allergic to soy milk. Many infants have soy allergies that they may eventually grow out of. 

If you do feed your child soy milk and they show signs of an allergy, symptoms include running nose, diarrhea, wheezing, and vomiting, then remove soy milk from their diet and check whether symptoms disappear. 

In case of a severe reaction, seek immediate medical attention. Your pediatrician will be able to give suggestions for milk alternatives too.

Soy milk is typically fortified and might have more calcium than dairy milk. However, soy milk also contains natural compounds known as phytates that can alter your body’s ability to absorb calcium, which is counter-intuitive but one of the reasons companies will fortify soy milk with extra calcium. 

This is one of the reasons we don’t recommend soy milk for babies, since most soy milks are fortified with a grown adult in mind. 

Consult a pediatrician if you are feeding your toddler with soy milk instead of dairy milk, breastmilk or formula. They will likely have other recommendations of foods to include in your child’s diet.

An indirect effect of feeding a baby soy milk is that they might feel fuller for an extended period. As a result, they will be less likely to consume other foods to meet their daily nutritional requirements. 

If you are giving a baby or child soy milk, make sure they consume other sources to ensure adequate nutrition.

Disadvantages of Soy Milk for Babies

There are a few additional disadvantages to feeding your baby soy milk. 

The main concern being that soy milk lacks necessary nutrition for growth and development of children, therefore it cannot be consumed as a complete meal replacement for breastmilk or baby formula. Additionally, the eating too much soy has proven significant risks to overall health.

Let’s discuss the disadvantages of soy milk for babies a bit further.

Soy milk contains isoflavones

Soy milk contains phytoestrogen, which is also known as isoflavones. Phytoestrogen has been linked to elevated levels of estrogen in the body, which may cause hormonal imbalances [2, 3, 4]. 

Both males and females can be negatively affected by elevated estrogen levels. In fact, research has connected the overconsumption of soy products at a young age to early puberty.

In fact, this same concern can be justified as a side effect of soy baby formula. More research needs to be done in this subject to fully determine the overall impact, but enough has been done to warrant a discussion.

Low Nutrition or Lack of Essential Nutrients

Soy milk does not contain the full profile of nutrients required by your baby to develop. 

While it does have a close nutritional profile to dairy milk, it is not an exact meal replacement. Therefore, only feeding your baby soy milk may bring about nutritional deficiencies. 

Additionally, soy milk, usually contains fewer total calories than dairy milk. One cup of soy milk has around 6g of protein and 105 calories, compared to one cup of whole milk which contains 8g of protein and around 150 calories. 

Though the numbers are not vastly different, it is 33% more protein and almost 50% more calories. Over time these variances are significant.

Soy baby milk side effects

Soy Milk for Babies Side Effects: Conclusion

As a plant based beverage, soy milk is one of the most common choices for parents to want to feed their child. Soy milk has  more protein than other plant milks, therefore it seems like a logical choice.

However, feeding your infant solely soy milk may lead to nutritional deficiencies since it doesn’t have the same profile as breastmilk or formula. 

Consider using soy milk as a supplement instead of a replacement for breast or dairy milk. If you want to continue offering soy milk to your infant, ensure you supplement the child’s nutrition from other sources for healthy growth and development. 

Be sure to test your child for soy allergies before making a complete shift. Soy is one of the leading allergens for babies, and must be observed to prevent major medical issues from arising.

Additionally, feed soy milk in moderation as too much soy products has shown signs of early puberty, so keep consumption to a minimum.

A pediatrician is the best option to give guidance on milk alternatives for your growing child. They will have recommendations for amounts and balanced diet requirements for your specific circumstance.

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