Nutritional Requirements for Babies

Good nutrition lays the foundation for healthy growth and development in the first year of life. When you feed a baby, you fuel their brain, bones and immune system.

Babies grow fast (really fast!). Which means their nutritional needs are much higher than you might think. And they’re changing.

During the first 6 months, a baby will typically double their birth weight. By their first birthday, they’ll have tripled it.

According to the World Health Organization,exclusive breastfeeding for the first six months can reduce the risk of infections, obesity and chronic disease later in life. Yet in the UK, we have some of the lowest breastfeeding rates in the world. Only 1% of babies are exclusively breastfed for the full six months. This shows a gap between public health guidance and real-world feeding practices.

As babies grow, solid foods play an important role too. But knowing when and how to introduce them can feel confusing. Here’s our guide on the nutritional requirements for a baby, from birth to weaning and beyond.

What are the nutritional requirements for a baby?

Babies are small, but their nutritional needs aren’t to be taken lightly. Their first year is their fastest for growth. They need the right balance of nutrients to support everything from brain development, strong bones and a healthy immune system.

If you’re exclusively breastfeeding, you’re in luck! Breast milk is the ideal first food for infants. It contains all of the nutrients and energy a baby needs. It adapts as the child grows and is safe, clean and full of antibodies to aid immune system development. It’s why many call it “liquid gold.”

Key Macronutrients a Baby Needs:

Protein

Protein helps build and repair cells. It’s used for muscle growth and development. It’s what helps babies grow bigger and stronger every day.

Both breastmilk and formula provide enough protein for babies. Once solids are introduced, good sources include lentils, beans, eggs, fish, chicken and yoghurt.

Fat

Fat often gets a bad reputation but it’s very important for babies. Fat helps brain development. It provides a major source of energy too.

Breastmilk and formula contain the right kinds of fat. Especially essential fatty acids like DHA, which supports brain and eye health.

Carbohydrates

These are the body’s main energy source. Babies get their carbs from the lactose in breastmilk and formula. Later, they get these from starchy foods like potatoes, rice, oats and wholegrains when solids begin.

Essential Micronutrients

Iron

Babies are born with iron stores that last about six months. After that, they need iron from their diet. This prevents anaemia and supports brain development. This is why iron-rich weaning foods like meat, pulses and fortified cereals are important.

Calcium

Calcium helps build strong bones and teeth. Babies get all the calcium they need from breastmilk or formula in the early months. Later, it comes from dairy foods like cheese and yoghurt.

Zinc

Zinc supports immune function and cell repair. It’s found in meats, dairy, wholegrains and some legumes. Babies need more zinc as they grow, especially after six months.

Iodine

Iodine plays a key role in brain development and thyroid function. It’s found in fish, dairy and eggs. It’s often added to formula.

For breastfed babies, mums need enough iodine in their own diet.

Hydration

Babies don’t need any extra water in the first six months. Breastmilk or formula provides all the fluid they need. Even in a heatwave! A baby will naturally want to feed more to combat the heat.

Once solids are introduced, small amounts of cooled, boiled water can be offered with meals to help them get used to drinking from a cup.

When to start introducing solid foods

Weaning is a big milestone in a baby’s life. It’s often an emotional one for parents too! But when’s the right time? And how do you get started with solid foods?

Signs Your Baby Is Ready for Solids

Most babies are ready for solid food at around 6 months old. But it’s less about the exact age and more about the signs of readiness.

Does your baby:

• Sit upright and holding their head steady?
• Have good hand-eye coordination? Can they pick things up and bring them to their mouth?
• No longer have the tongue-thrust reflex? That means they’re not pushing food back out with their tongue.
• Show interest in food? Do they watch you eat or try to grab your food?

Premature babies often start weaning differently, so speak to your health visitor or GP for personalised advice.

What to Offer First

There is a lot of debate about weaning. Should you do the old-fashioned way of purees and jars? Should you do finger foods and follow baby-led weaning?

Whichever method you choose, start with simple, single-ingredient foods. These should be soft and easy to digest. Iron-rich foods are a good place to begin because your baby’s iron stores start to run low around six months.

Good first foods include:

• Puréed or mashed vegetables (carrot, sweet potato, parsnip).
• Soft fruits (banana, avocado, cooked apple or pear).
• Iron-rich options like lentils, beans or puréed chicken.
• Baby rice or iron-fortified cereals mixed with breastmilk or formula.

Avoid adding salt, sugar or honey. Babies’ kidneys can’t handle added salt, and honey should be avoided under 12 months due to the risk of infant botulism.

Texture

Weaning isn’t just about what babies eat – it’s also about how they learn to eat. Those who start with smooth purées or mashed food, should gradually offer lumpier textures and soft finger foods like:

• Soft toast fingers
• Cooked pasta
• Slices of ripe fruit or well-cooked veg

Introducing a variety of textures early on helps babies develop chewing skills and may reduce fussiness later.

Allergens and Variety

There’s good evidence that introducing common allergens early – between 6 and 12 months – can help reduce the risk of allergies later.

These include:

• Peanut
• Egg
• Cow’s milk (in cooked food)
• Gluten (wheat, barley, rye)
• Fish

Offer new foods one at a time, in small amounts, and watch for any reaction. If you have a family history of allergies or your baby has eczema, speak to your GP or health visitor before introducing allergens.

Vitamins for babies

Breastmilk or formula provides most of what a baby needs in the early months. But there are a few vitamins that may need extra attention. This is especially true as they grow and begin eating solids.

Vitamin D

Vitamin D is essential for healthy bones and teeth. It helps the body absorb calcium and phosphorus. The problem is that it’s hard to get enough from food or sunlight alone, especially in the UK. A 2016 government-commissioned report states that everyone should consider taking vitamin D supplements in the autumn and winter months. For people of colour, this should be all year round.

The NHS recommends that:

• All babies under 1 year should be given a daily vitamin D supplement of 8.5 to 10 micrograms, unless they’re having more than 500ml of formula a day (as formula is already fortified).

Breastfed babies, even from birth, need a supplement. Because breastmilk doesn’t contain enough on its own.

From 1 to 5 years old, all children should continue with a daily vitamin D supplement, especially during autumn and winter.

Vitamin A

Vitamin A supports your baby’s immune system, vision and skin. It’s found in dairy products, eggs, oily fish, and orange or dark green vegetables like carrots, sweet potatoes and spinach. While babies get some from breastmilk and formula, they may need a boost as they start solids.

Vitamin A is included in the NHS’s Healthy Start vitamin drops. These are recommended for children from six months to five years old if they’re not getting enough from their diet.

Vitamin C

Vitamin C helps with iron absorption and supports immunity. Babies usually get plenty from a varied diet that includes fruits and vegetables. Especially things like strawberries, broccoli, peppers and citrus fruits. It’s also present in breastmilk and formula.

Supplements aren’t normally needed unless advised by a healthcare professional. Vitamin C is also included in Healthy Start drops for babies who need them.

Vitamin K

Newborns are often given a vitamin K injection at birth. This helps prevent a rare but serious condition called vitamin K deficiency bleeding (VKDB). The injection is standard in most UK hospitals and is strongly recommended, though some parents opt for an oral version instead.

After this initial dose, breastfed babies continue to get some vitamin K through breastmilk. Formula is fortified with it.

As solid foods are introduced, green leafy vegetables, meat and dairy help maintain healthy levels.

Breastfeeding

Breastfeeding is the most natural ways to feed a baby. It offers brilliant benefits for both babies and mums.

Why Breastmilk Is Special

Breastmilk is often described as a “living food.” This is because it adapts to meet your baby’s changing needs. It contains the perfect mix of proteins, fats, vitamins and antibodies to help your baby grow and fight off illness.

Some of the well-known benefits of breastfeeding include:

• Boosted immunity. Breastmilk contains antibodies that protect against infections like colds, diarrhoea and chest infections.
• Brain development. It contains long-chain fatty acids like DHA. This supports brain and eye development.
• Digestive health. It’s easier to digest than formula and may reduce the risk of constipation and colic. Breastfed babies often require less winding than formula-fed babies.
• Lower risk of illness later. Studies link breastfeeding with a significantly reduced risk of obesity, type 2 diabetes and even some allergies in later life.
• Bonding and comfort. Skin-to-skin contact and the closeness of breastfeeding can soothe and calm both baby and parent.
• Protection against diseases in the mother. Breastfeeding mothers have better protection against breast and ovarian cancers and heart disease. It also lowers your risk of osteoporosis and obesity. The longer you breastfeed, the greater the benefits.

How Long Should You Breastfeed?

UK health guidelines, in line with the World Health Organization, recommend exclusive breastfeeding for the first six months. After that, breastmilk can continue alongside solid foods for as long as both mother and baby want.

The natural weaning age of humans varies. Ancient texts like those written by Aristotle (384 to 322 BC) reference babies breastfeeding to 18 months. Or until the mother’s menstrual cycle returned. In Ancient Hebrew scripts, it is common to see references to children still nursing at three years old.

Whether you breastfeed for days, months or years, every drop counts.

Getting Support

Breastfeeding can take practice. It’s normal to have questions or challenges along the way. In the UK, support is available through:

• Midwives and health visitors.
• Local breastfeeding support groups.
• The National Breastfeeding Helpline (0300 100 0212).
• La Leche League and other peer support networks.

Nutrients in Formula

Infant formula is the next best alternative to breastmilk. It’s designed to provide all the essential nutrients a baby needs to grow and thrive in the first year of life. Whether you’re formula feeding from birth, combining with breastfeeding or switching later on, it’s reassuring to know that modern formula milk is highly regulated and nutritionally complete.

What’s in Formula Milk?

All infant formulas sold in the UK must meet strict compositional and safety standards. This means they include:

• Carbohydrates. Usually in the form of lactose, similar to breastmilk
• Proteins. Often derived from cow’s milk. But it’s altered to be easier to digest.
• Fats. Including essential fatty acids for growth and brain development
• Vitamins and minerals. Such as iron, calcium, vitamin D and iodine
• Added nutrients. Like DHA (an omega-3 fatty acid), which supports eye and brain development

Some formulas also contain prebiotics and probiotics to support gut health, though evidence on their long-term benefits is still developing.

Types of Formula

There are a few different kinds of formula available:

• First infant formula. Suitable from birth and often the only one needed throughout the first year
• Follow-on formula. Marketed for babies from 6 months, but not necessary if your baby is eating solids and still having first formula or breastmilk.
• Specialist formulas. For babies with allergies or digestive issues (more on this in the next section).

It’s worth noting that first infant formula is all your baby needs for their first 12 months.

The International Code and Resolutions prohibit all forms of advertising and promotion of breastmilk substitutes. This includes follow-on formula and toddler milks. There is also a ban on advertising bottles and teats. In the UK, however, the law only prohibits the advertising and promotion of infant formula. Follow-on formula can be promoted and advertised. This loophole means there is widespread advertising of these products.

Is Formula as Good as Breastmilk?

Formula doesn’t contain the live antibodies and adaptive qualities of breastmilk. However, formula-fed babies can still grow up healthy, strong and well-nourished. The most important thing is that your baby is fed responsively. Overfeeding is much easier with a bottle and is more common.

Preparing Formula Safely

If you’re using formula, it’s important to prepare it safely to avoid the risk of infection. This is the way to prepare formula safely, per NHS guidelines.

1. Boil fresh tap water.
2. Leave to cool for no more than 30 minutes. It should be at least 70°C.
3. Clean and disinfect the surface used and wash your hands.
4. Use a sterilised bottle and teat. If you’re using a cold-water steriliser, you should shake off any solution remaining and rinse the bottle and teat with some of the cooled boiled water.
5. Place the bottle on the clean surface.
6. Follow the manufacturer’s instructions and pour in the required amount of cooled boiled water into the bottle.
7. Add the right amount of powdered formula.
8. Add the teat and cap and shake to dissolve the powder.
9. Cool the formula by running the bottle under cold running water with the cap on.
10. Test the temperature first before feeding.
11. Throw away any unused formula.

Babies Who Need Special Nutrition

Some babies may need extra nutritional support due to medical conditions, allergies or premature birth. It’s always best to work closely with your GP, paediatrician or health visitor if your baby has special dietary needs.

Babies Born Prematurely

Babies born before 37 weeks often have higher nutritional requirements. Their bodies are still catching up in terms of growth, immune development and fat stores. Depending on their birth weight and health, they might need:

• Specialist premature baby formula. This contains higher amounts of calories, protein, vitamins and minerals
• Breastmilk fortifiers. If they’re being breastfed, to give an extra boost of nutrients
• Close growth monitoring. To track weight, length and head size

Feeding a premature baby can feel a bit different at first. Tube feeding is sometimes needed in the NICU but healthcare professionals are there to guide you.

Babies With Cow’s Milk Protein Allergy (CMPA)

CMPA is one of the most common food allergies in babies. It affects around 7% of formula-fed babies and 0.5% of babies who are exclusively breastfed.

CMPA symptoms:

• Eczema or skin rashes.
• Diarrhoea, vomiting or colic.
• Blood in stools.
• Poor weight gain.

If CMPA is suspected, your baby may be prescribed a specialised hypoallergenic formula. This may be an:

• Extensively hydrolysed formula (EHF). Where the cow’s milk proteins are broken down.
• Amino acid formula (AAF). For more severe cases.

Breastfed babies can still react if their mum consumes dairy. A dairy-free diet for the breastfeeding parent might be advised. Again, always seek medical advice before making dietary changes.

Babies With Other Allergies or Digestive Conditions

Some babies may need tailored nutrition due to:

• Lactose intolerance – Rare in infants, more common after age one.
• Gastroesophageal reflux (GORD) – Sometimes managed with thickened feeds or specific formulas.
• Metabolic disorders – This requires precise medical nutrition plans

In these situations, a paediatric dietitian will often be involved to ensure your baby gets all the nutrients they need while managing their condition.

When to Seek Help

If you notice any of the following, speak to your GP or health visitor:

• Frequent vomiting or diarrhoea.
• Excessive crying after feeds.
• Poor weight gain or growth.
• Ongoing rashes or signs of discomfort.
• Concerns about allergies or intolerances.

Early support can make all the difference in getting feeding back on track. And ensuring your baby’s nutritional needs are met safely.

Conclusion

Feeding a baby isn’t always straightforward. Understanding their nutritional needs is a great place to start. Whether you’re breastfeeding, formula feeding or doing a bit of both, what matters most is that your baby is healthy and growing.

From birth through weaning and beyond, babies rely on us to help them build strong foundations. That means choosing nourishing options, looking out for signs of any issues and not being afraid to ask for help when needed.

The early days are full of learning curves, but you’re not alone. There’s a whole network of support out there – midwives, health visitors, dietitians and trusted sources like the NHS – to help you make informed choices that work for your baby and your family.

With the right knowledge and support, you can feel confident that you’re giving your baby the very best start.