Best Vegan Baby Formula
  • Alyssa Fontaine, RD
  • Jul 31, 2023

Best Vegan Baby Formula: Nourishing Your Little One with Plant-Powered Nutrition

As vegan dietitians, one of the most frequent questions we encounter is: “What is the best vegan baby formula?” In particular, there is often curiosity and concern about soy-based baby formulas. Today, we embark on a comprehensive exploration of soy-based baby formula, shedding light on its nutritional aspects, benefits, and potential considerations.

Our aim is to provide parents and caregivers with well-informed insights to assist them in making the best choices for their little ones’ nourishment. Let’s delve into the world of soy-based baby formula and navigate the facts together.

Soy-Based Baby Formula

Breastfeeding has been considered the gold standard for infant nutrition and feeding. In fact, the World Health Organization recommends that infants should be exclusively breastfed for the first six months of life. However, for several reasons, formula feeding may be necessary. 

A variety of different formula options exist on the market for infants less than 12 months old. In this article, we discuss a soy-based baby formula as the best, and only option for vegan and vegetarian mothers. 

Is Baby Formula Naturally Vegan?

No, standard baby formula is based on modified cow’s milk, making it an animal product.

Different Types of Baby Formulas

For infants who do not breastfeed, regular cow’s milk is generally recommended. However, there are multiple types of other formulas sold for clinical and non-clinical reasons. 

  • Special formulas for premature babies
  • Infants with allergies
  • Lactose-free formulas
  • Specific nutritional needs (ex: fa malabsorption, phenylketonuria) 
  • Partially hydrolyzed formulas to help with colic, baby fussiness, of perceived gastrointestinal issues

Indications for Soy-Based Formula

Evolution of the Soy-Based Formula

Soy-based formulas have been safely given to infants for the past 80 years providing them with the necessary nutrients for proper growth and development. In fact, soy-based infant formula which was initially developed for infants with lactose intolerance or allergies to cow’s milk, now account for over 25% of all infant formula sold in the United States. 

Formulations have improved since their introduction. Although the formulas have always been lactose free, the protein sources have changed. Initially, soy-based infant formulas were made with soy flour as the protein source, whereas the majority of soy formulas produced now have adopted a more refined protein source, namely soy protein isolate.

What are Soy-Based Baby Formulas Made of?

Soy formulas, often known as “plant-based formulas,” are the preferred option for many vegan families due to their widespread availability. Although the soy protein-based formulas available in stores do not contain cow milk-protein or lactose, they are enriched with iron and fulfill nutrient requirements for feeding full-term infants.

Energy: They are designed to provide 67 calories per 100 mL of formula.

Protein: Soy-based formulas are based on fortified soy protein isolate enriched with the following:

  • L-methionine: Responsible for improved weight gain, get rid of waste substances (urea nitrogen), and produce albumin, a vital protein in the body.
  • L-carnitine: Necessary for helping the body’s cells use energy effectively
  • Taurine: antioxidant properties 

Fat: The fat content of soy protein-based formulas is derived primarily from vegetable oils, including soy, palm, sunflower, olein, safflower, and coconut.

Carbohydrates: Since plants lack lactose, soy formulas utilize alternative sources like corn syrup, corn maltodextrin, brown rice syrup, or sugar to provide the necessary carbohydrates.

Is Soy-Based Formula Safe for Babies?

Many people question whether soy-based baby formulas are good or bad for their babies due to it containing isoflavones and its role on the body. This is understandable since babies fed soy formula consume more soy isoflavones compared to babies on other formulas. 

In fact, since formula provides their sole source of nutrition during the first six months of life, these infants typically consume more soy isoflavones than most adults who occasionally eat soy. So let’s see what science has to say about this:


  • Concerns about soy formula come from its phytoestrogens content. These phytoestrogens are natural plant compounds called isoflavones, which have been related to the reproductive system. 
  • Specifically, concerns that isoflavones are associated with the hypothesis that isoflavones could have estrogen-like effects in the body, potentially affecting various physiological processes. 
  • However, the absence of this effect was seen in more recent case studies with one study demonstrating that the patterns of growth and reproductive functions are similar to infants consuming human milk. 

Immune function:

  • Moreover, previous studies have suggested that the intake of isoflavones, therefore infants who feed with soy formula may develop impaired immune function. However, more modern studies examining soy based infant formulas were shown to support immune system development in young, growing infants.


  • Finally, in one study, babies who were given soy flour formulas experienced higher losses of thyroxine, a hormone produced by their thyroid. In contrast to this study, others have shown slightly higher thyroxine levels.
  • Overall, the current soy protein isolate based infant formulas support normal growth and development, and infants fed these formulas do not exhibit the slow growth typically associated with hypothyroidism.

Taken together, scientific studies have not found any significant long-term effects in babies fed soy formula, including no adverse impact on sexual development in the brain, immune function or thyroid function.

For more information on isoflavones in soy-based baby formula, consult one of our vegan registered dietitians

Is Vitamin D Vegan?

The short answer is no. Food is typically considered vegan if it completely avoids all animal products whenever feasible. Even the slightest presence of an animal ingredient in a formula can cause some people to view it as non-vegan.

All plant-based or soy-based formulas available on the market contain vitamin D3, which is derived from lanolin, a wax secreted by sheep wool and therefore not vegan. 

Vitamin D2 is the vegan alternative to this nutrient, but it is less effective in raising active vitamin D levels. Although vegan versions of D3 exist, such as those derived from lichen or mushrooms, they tend to be more expensive and harder to obtain.

As a result, formula companies often opt for cheaper and more accessible options, which means that most formulas are not completely 100% vegan.

Are Soy-Based Formulas Better Than Cow’s Milk?

Federal regulations in the United States of America and Canada ensure that soy-based formulas contain the same caloric content and essential nutrients as other approved baby formulas, including those made with cow’s milk. 

These regulations also define nutrient levels in infant formula and establish quality control procedures, providing assurance that your baby’s growth and developmental needs will be met adequately.

Soy protein formulas support the normal growth and development of healthy full-term infants. However, they do not offer any nutritional advantages compared to formulas containing cow’s milk protein. 

They are mainly recommended for infants with severe lactose intolerance, galactosemia, or the need to avoid animal-based foods. It’s important to note that there is no supporting evidence that soy protein is effective in preventing allergies or managing non-specific gastrointestinal symptoms like colic and regurgitation.

They should not be used for preterm infants or infants with food allergies before the age of 6 months. After 6 months, if your baby tolerates soy protein well, you may consider using soy protein formulas.

When to not use soy-based formulas? 

Congenital hypothyroidism

As previously mentioned, before the mid-1960s, soy formulas lacked high-fiber soy flour as the protein source. Additionally, they also lacked iodine supplementation and as a result, there were reported cases of goiter and hypothyroidism in infants who were fed this formula. 

However, since the transition to soy protein isolate and the addition of iodine to the formulas there are still observations of thyroid insufficiency in infants with congenital hypothyroidism who were fed soy protein formulas.

So what does this mean? It means that despite this improvement in the content of soy formulas, some infants with underlying thyroid issues may still experience thyroid-related problems and therefore should be avoided. 

It’s important to consult with your vegan dietitian before introducing a vegan formula to your newborn.

Acute Gastroenteritis 

Studies looking at the effects of nutrition on children with acute gastroenteritis has shown that most infants with acute gastroenteritis can continue using their regular lactose-containing formula, as it does not worsen the condition. Only in very severe cases could it be beneficial. 

However, switching to lactose-free formula as a routine measure is not recommended, and there are concerns about introducing new protein sources in infants with gut issues. Always consult a healthcare professional or a vegan dietitian for personalized advice.

Preterm infants 

Soy formula is not recommended for preterm infants because studies have shown that they have a higher risk of developing osteopenia, possibly due to their underdeveloped kidneys being unable to properly excrete aluminum. As aluminum competes with calcium for absorption and soy formula contains more aluminum than breast or cow’s milk, it may not be suitable for preterm infants.

Prevention of Atopic Diseases

Atopic diseases are a group of conditions characterized by an increased sensitivity to allergens and a tendency to develop allergic reactions. This becomes particularly concerning for infants who develop a milk protein allergy, since this is their only source of nutrition for the first 6 months of life. 

In cases like these, however, it is not recommended to use intact soy protein isolate as the initial treatment since soy is also an allergen. Although a proportion of infants with cow’s milk allergies tolerated a soy-based formula, soy, itself, is a common allergen. 

In general, controlled human trials have not supported the use of soy for controlling allergies and a recent meta analysis showed how a soy-based formula does not prevent food allergies in high-risk infants. Therefore, soy protein should not be recommended as a treatment to a cow’s milk protein allergy. 

Soy Allergies

Specifically, soy-based infant formulas are not recommended for infants with soy allergies.  Although most infants eventually outgrow soy allergies, it can persist into adulthood. Common symptoms of soy allergy include:

  • Hives, itching in the mouth
  • Abdominal pain, diarrhea, nausea
  • Eczema
  • Flushing, swelling of the lips, face, tongue, throat, or other body parts
  • Wheezing, runny nose, and difficulty breathing
  • In rare cases, anaphylaxis could occur

If you suspect your baby has a soy allergy, it’s essential to consult their doctor, who may refer you to an allergist for a proper diagnosis.

Do vegan babies need supplements?

For vegan infants, the supplementation guidelines are generally similar to those for non-vegan infants, except for vitamin B-12, which needs to be supplemented. 

Depending on the situation, special attention should also be given to vitamin D.

Vitamin B12

Ensuring sufficient vitamin B12 intake in the first six months is highly crucial for the baby’s health. The Institute of Medicine (IOM) advises that vegan babies should receive a vitamin B12 supplement from the time of birth.

Soy formula does contain vitamin B12 in specific quantities, but it’s essential to consult with your pediatrician to confirm if the amount is appropriate for your baby.

Vitamin D

All children younger than 12 months old should receive a vitamin D supplement of 10 mcg (400 IU) per day and children 12 to 24 months old need 600 IU of vitamin D each day as recommended by the CDC.

Soy protein-based formulas are supplemented with lanolin-derived vitamin D3 in specific quantities, but you must check this with your pediatrician to ensure it is adequate for your baby. 

Is Homemade Baby Formula Safe?

NO! In one quick search, you can find a whole host of vegan homemade formulas. However, these are completely unsafe and should never be used! 

The introduction of the Internet has led to several benefits when it comes to finding information for parents and physicians alike. However, this convenience has also led to potential harm caused by misleading information available online. 

Two case studies have been reported on infants given homemade infant formulas that resulted in detrimental results. 

  • The first showed a baby suffering from a seizure-like episode characterized by stiffening of the limbs, bluish discoloration around the mouth, and temporary cessation of breathing for several minutes after vomiting following a feeding. 
  • The second case involved an infant who was brought to the hospital by ambulance due to sudden and severe difficulty in breathing after waking from a nap. At the time of arrival, the infant was in severe distress and required cardiopulmonary resuscitation (CPR) in order to bring the baby back to life

In general, it is best to consult with a healthcare professional or vegan dietitian when deciding on your child’s nutrition in order to make sure it’s safe and meeting all their needs.

Best Vegan Newborn Formulas: 

This is our selection of the best vegan newborn formulas. If you’re still not sure which one to choose for your baby’s needs, consult a vegan registered dietitian

Nestlé Good Start alsoy baby formula 

Soy-based, dairy-free complete nutrition
Lactose-free and easy to digest 
Designed for babies avoiding cow’s milk or dairy products
Kosher, halal
Vegan source of DHA

Similac Isomil with DHA baby formula 

Vegan-sourced DHA from algae
Corn syrup is listed as the main carbohydrate ingredient

Gerber Good Start Soy Protein Infant Formula

Uses maltodextrin as the main source of sweetener 
Vegan-sourced DHA from algae
Often out of stock
Can constipate

EARTH’S BEST organic soy-based formula 

Kosher Certified 
Omega-3 DHA fortified from algae vegan source
Organic corn syrup is used as the main source of carbohydrate

Sprout organic plant-based infant formula  

No sugars added 
DHA fortified from vegan-sourced algae 
Vegan-sourced vitamin D2
Australia-based – only purchased online in US and Canada 

Summary: Best vegan baby formula

In conclusion, choosing the best vegan baby formula is a crucial decision to ensure your little one receives optimal nutrition during their early stages of life. By opting for a high-quality, plant-based formula, you can provide essential nutrients for your baby’s growth and development while adhering to your ethical and dietary preferences.

For personalized guidance and expert advice on raising a healthy vegan baby, consider consulting a plant-based dietitian. They can provide valuable insights, tailored meal plans, and address any specific concerns you may have. Invest in your baby’s well-being by seeking professional support and nurturing their growth on a wholesome plant-based diet.

© All Rights Reserved, Plant-Based Dietitians 2024