From breast milk and infant formula to cow’s, goat’s, and plant-based alternatives, the world of milk can feel overwhelming for new and seasoned parents alike. Each stage of a child’s development brings different nutritional needs—and not all milk is created equal when it comes to supporting healthy growth.
In this guide, we break down the most common types of milk, compare their nutritional profiles, and provide age-specific recommendations backed by pediatric guidance. Whether you're deciding between soy or oat milk, wondering when to introduce dairy, or figuring out how long to use formula, we’ve got you covered with evidence-based answers.
Key Nutritional Takeaways
The table below summarizes approximate nutrient values per 100 ml for breast milk, dairy milks (whole, low-fat, lactose-free), and common plant-based milks (fortified soy, almond, oat, pea). Values are approximate and assume unsweetened versions; many plant milks are fortified with calcium (Ca) and vitamin D (D) during processing. (Note: breast milk composition varies, but mature milk provides ~65–70 kcal/100 ml with ~3.5–4 g fat, ~1 g protein and ~7 g sugar. It naturally contains only ~25 mg Ca/100 ml and very little vitamin D, so breastfed infants need supplementation.)
| Milk type | Calories (kcal) | Protein (g) | Fat (g) | Calcium (mg) | Vitamin D | Sugar (g) |
|---|---|---|---|---|---|---|
| Breast milk | 65 | 1.0 | 3.6 | 25 | 0 (traces) | 7.0 |
| Cow (whole, 3.5%) | 65 | 3.4 | 3.7 | 124 | ~40 IU (fortified) | 4.7 |
| Cow (low-fat, 1%) | 47 | 3.6 | 1.8 | 124 | ~40 IU (fortified) | 4.8 |
| Cow (lactose-free, 3.5%) | 65 | 3.4 | 3.7 | 124 | ~40 IU (fortified) | 4.7* |
| Goat milk | 64 | 3.2 | 3.8 | 103 | 0 (traces) | 4.5 |
| Soy milk (fort.) | 41 (per 100 ml) | 3.1 | 1.7 | 153 | 50 IU | 0.4 |
| Almond milk (fort.) | 30 | 1.0 | 2.5 | 120 (est.) | 80 IU (est.) | 0 (unsweetened) |
| Oat milk (fort.) | 47 | 1.0 | 1.5 | 150 (est.) | 50 IU (est.) | 6.7 (est.) |
| Pea milk (fort.) | 62 | 3.3 | 1.9 | 188 (est.) | 50 IU (est.) | 7.0 (est.) |
*Values for cow’s lactose-free milk are essentially the same as regular whole milk (lactose is split into glucose/galactose).
- Breast milk: Optimal for infants, providing balanced nutrients for growth. It delivers about 65–70 kcal per 100 ml (≈20 kcal/oz) with fat as ~50% of calories. However, breastmilk is low in vitamin D (virtually none) and modest in calcium (~25 mg/100 ml), so breastfed babies need supplemental vitamin D. (Sources: cdc.gov, nih.gov)
- Infant milk formula: Designed to replicate the nutritional profile of breast milk, standard iron-fortified infant formulas provide similar calories (~66–70 kcal/100 ml), with slightly higher protein (~1.3–1.5 g) and added calcium (~40–50 mg) and vitamin D (~40–60 IU) to meet infant needs. Unlike plant or animal milks, formula is safe and complete nutrition for babies under 12 months. (Sources: similac.ca, canada.ca)
- Dairy vs. plant milks: Cow’s and goat’s milks are naturally rich in protein (~3–3.4 g/100 ml) and calcium (~100–125 mg/100 ml). Dairy milks also contain lactose (~4–5 g/100 ml) as sugar and are usually fortified with vitamin D in the U.S. (about 2.5 μg per cup, or ~40 IU/100 ml). Goat’s milk is similar to cow’s in fat and protein. (Source: milk.co.uk)
- Soy milk: Among plant milks, fortified soy milk is most comparable to dairy in protein and calcium. A calcium-fortified unsweetened soy milk has about 3–3.5 g protein and 150–370 mg calcium per cup (≈40 kcal and 3 g protein per 100 ml). Thus fortified soy can count toward the dairy group in dietary guidelines. (Sources: rochester.edu, fda.gov)
- Almond/oat/pea milks: These tend to have much less protein (often only ~0.5–1 g/100 ml) than dairy. They must be fortified to provide calcium and vitamin D. For example, many almond milks (unsweetened) are very low in protein (~1 g/100 ml) and owe their nutrients to fortification. Plant milks also vary in natural sugars: cow’s milk has ~5 g lactose/100 ml, whereas unsweetened soy/almond have almost no sugar, oat and pea milks contain more (from the grain or added sweeteners). (Sources: fda.gov, rochester.edu)
The FDA notes that only fortified soy beverages have nutrient contents (protein, calcium, vitamin D) close enough to be considered equivalent to milk in the U.S. Dietary Guidelines. Other plant “milks” can be nutritious but vary widely by brand and fortification. When choosing a plant milk for children, experts recommend checking that it is fortified and noting its protein content.
Age-Specific Guidance
0–12 months:
Exclusive breast milk or iron-fortified infant formula is recommended for the first 6 months of life, and breastfeeding is encouraged for at least 12 months. Infant formula is the only suitable alternative when breastfeeding isn't possible or is supplemented.
Neither cow’s milk nor plant-based milks should be used as a main drink for infants under 1 year.
Breast milk and standard infant formula provide all essential nutrients (~65–70 kcal/100 ml, ~3–4 g fat, ~1.3–1.5 g protein). However:
- Breastfed infants need 400 IU of supplemental vitamin D daily, as breast milk is low in vitamin D.
- Formula-fed infants usually do not require additional vitamin D, as formulas are fortified (~40–60 IU/100 ml).
12–24 months (Toddlers):
After age 1, whole cow’s milk becomes the standard. U.S. dietary guidelines (CACFP/AAP) recommend unflavored whole milk unless otherwise advised by a pediatrician.
The fat in whole milk supports brain development and energy needs.
- Breastfeeding can continue as long as mutually desired.
- Toddlers typically need 2–3 cups per day of milk (or equivalent: breast milk, formula, or fortified soy milk) to meet calcium and vitamin D needs.
- Fortified soy milk is the only plant milk considered nutritionally equivalent to cow’s milk at this age.
2 years and older:
At age 2, transition to low-fat (1%) or nonfat (skim) milk is recommended to support heart health while still providing calcium and protein. Children should consume about 2–2½ cups (16–20 oz) of dairy or fortified alternatives daily.
Flavored milk should be limited due to added sugars.
By kindergarten age (4–6 years), children can meet their calcium and vitamin D needs from a variety of foods (including dairy or fortified plant milks), with an emphasis on balanced meals.
Common Myths About Milk for Babies and Toddlers
Myth 1: “Infant formula is better than breast milk.”
While infant formula is carefully designed to meet an infant’s nutritional needs and provides adequate vitamin D (which breast milk lacks), breast milk remains the gold standard. Breast milk contains unique antibodies, enzymes, and bioactive compounds that formula cannot replicate. Formula is an excellent and safe alternative when breastfeeding is not feasible, but it doesn’t fully replace the comprehensive benefits of breast milk.
Myth 2: “Breast milk isn’t enough after 6 months, so formula is better.”
Breast milk alone is sufficient for about the first 6 months and continues to provide essential nutrients and immune support beyond that when combined with solids. Formula is a nutritionally balanced alternative when breastfeeding isn’t possible but lacks the unique immune factors in breast milk.
Myth 3: “All plant milks are just as nutritious as cow’s milk.”
Not true! Most plant-based milks like almond, oat, or rice milk have much less protein and often rely heavily on fortification for calcium and vitamin D. Only fortified soy milk closely matches cow’s milk nutritionally, especially for toddlers.
Myth 4: “Goat milk is a hypoallergenic alternative to cow’s milk.”
Goat milk contains many of the same proteins as cow’s milk and can still trigger allergies or intolerances. It’s not a safe substitute for children with diagnosed dairy allergies or lactose intolerance.
Myth 5: “Cow’s milk can be introduced before 1 year.”
Giving cow’s milk before 12 months is not recommended due to risks like iron deficiency and digestive issues. Babies under 1 year should be exclusively breastfed or fed infant formula.
Myth 6: “Flavored milks are a healthy way to get kids to drink milk.”
Flavored milks often contain added sugars and should be limited, especially in toddlers and young children, to avoid excess calorie intake and dental issues.
Myth 7: “Lactose intolerance is very common in infants.”
True lactose intolerance is rare in infants; most babies can digest lactose in breast milk or formula. Symptoms often attributed to lactose intolerance may actually be due to other issues like milk protein allergy or digestive immaturity.
Myth 8: “Plant-based milks are always dairy-free.”
While most plant milks are dairy-free, cross-contamination or added ingredients may introduce dairy traces. Always check labels, especially if allergies are a concern.
Frequently Asked Questions About Milk for Babies and Toddlers
Q: When can I start giving my baby cow’s milk?
A: Cow’s milk should not be given as a main drink before 12 months of age because it lacks the right balance of nutrients for infants and may cause iron deficiency. Use breast milk or iron-fortified formula exclusively for the first year.
Q: Is infant formula just as good as breast milk?
A: Infant formula is a safe and nutritionally complete alternative to breast milk when breastfeeding isn’t possible. However, breast milk contains unique antibodies and immune factors that formula can’t replicate.
Q: Is using a bottle warmer recommended for heating breast milk or formula?
A: Yes, bottle warmers are a recommended and convenient way to gently warm breast milk or formula to a safe, comfortable temperature. They help preserve nutrients and avoid the hot spots that microwaving can cause. However, warming isn’t strictly necessary—room temperature or slightly chilled milk is safe to feed if your baby accepts it. Ultimately, use whatever method works best for you and your baby’s feeding routine.
Q: Can I mix breast milk and formula in the same bottle?
A: Yes, you can mix breast milk and formula, but it’s best to prepare fresh formula and feed immediately to reduce risk of bacterial growth.
Q: What’s the best milk alternative if my child is allergic to cow’s milk?
A: For milk allergy, hypoallergenic or amino acid-based formulas are usually recommended for infants. For older children, fortified soy milk is often the best plant-based alternative, but always consult your pediatrician.
Q: Is soy milk safe for toddlers?
A: Fortified soy milk can be a suitable alternative to cow’s milk for toddlers over 12 months, especially if they have dairy allergies or intolerances. Make sure it is unsweetened and fortified with calcium and vitamin D.
Q: Are almond, oat, or pea milks good choices for young children?
A: These milks tend to have low protein and varying calcium and vitamin D levels unless fortified. They’re generally not recommended as primary milk sources for infants and toddlers.
Q: Should I worry about lactose intolerance in my baby?
A: True lactose intolerance is rare in infants. If your baby has symptoms like diarrhea or fussiness after feeding, consult a healthcare provider to rule out other causes such as milk protein allergy.
Q: How much milk should my toddler drink each day?
A: Toddlers generally need 2–3 cups (16–24 oz) of milk or milk equivalent daily to meet calcium and vitamin D needs, alongside a balanced diet of solids.
Q: Do breastfed babies need vitamin D supplements?
A: Yes, breastfed infants should receive a daily vitamin D supplement (400 IU) since breast milk alone is low in vitamin D.