Baby's Immunity: How to Strengthen Their Natural Defences?

From pregnancy onwards, your baby begins to build their immune system. 

Here are the key stages:

• During pregnancy: maternal antibodies cross the placenta and protect the foetus — this is known aspassive immunity.
• At birth: the newborn still benefits from maternal antibodies, but its own immune system is immature — it is particularly vulnerable to infections.
• In the first months: the baby's immune system gradually develops, in particular thanks to breastfeeding (the mother's antibodies are present in breast milk), through vaccines and controlled exposure to microbes.
• After 6 months: maternal antibody reserves are depleted, and the baby begins to produce its own defences, but it remains vulnerable to infections.

Did you know that the gut microbiome plays a key role in immunity? This collection of micro-organisms colonises the intestines and supports the development of the immune defences. A balanced gut flora helps protect baby against infections and allergies.

A strong immune system allows your baby to:

• Fight infections more effectively (colds, gastroenteritis, ear infections, etc.)
• Reduce the risk of allergies
• Respond better to vaccines
• Develop better long-term health

Studies show that the first 1,000 days of life, from conception to the child's second birthday, are crucial in determining their future health.

The mother's diet

Your baby's immune system begins to develop during pregnancy. The mother passes on part of her microbiome to her baby. 

For a healthy gut microbiome that supports your baby's wellbeing, you can opt for a varied and nutritious diet, rich in fibre, vitamins and minerals (in particular vitamins A, B, C, D, E, magnesium, iron, zinc, copper, selenium and omega-3s). It is also advisable to limit coffee, ultra-processed foods, fried foods and sugary products.

During pregnancy, opt for probiotics in capsule form. To choose quality products with the strains suited to your needs, do not hesitate to consult a naturopath specialising in pregnancy and the post-partum period. Outside of pregnancy, you can incorporate probiotics through food: lacto-fermented vegetables (gherkins, sauerkraut, kimchi…), miso, artisan sourdough, active brewer's yeast, fermented drinks (kefir, kombucha) and unpasteurised yogurts. 

Breastfeeding and your baby's diet

Colostrum, the fluid produced by the mammary gland during pregnancy and up to 3 days after birth, is extremely rich in antibodies, nutrients and growth factors. It protects the newborn against infections, supports the colonisation of the intestinal microbiome and reduces the risk of allergies. Breast milk also contains antibodies, natural probiotics and essential nutrients. Breastfeeding is therefore a good choice for your baby's immune system, but it is a personal decision that cannot be guided by this reason alone. 

Mothers who do not wish to breastfeed can offer their baby a welcome feed. This is the first feed after birth, which allows the baby to benefit from colostrum. You can also collect the colostrum and give it by teaspoon, syringe or bottle.

To enrich your baby's gut flora, you can also give them a course of probiotics. The Lactobacillus reuteri Protectis strain has been the subject of numerous clinical studies.

Gradually, your baby will discover a varied diet. Offer as much as possible whole, fresh, local and seasonal produce, and put together colourful, varied plates rich in fibre, vitamins and minerals. 

Bathing and nasal care

The WHO recommends not bathing a newborn during the first 24 hours of life. You can even wait several days, or more than a week, before the first bath. This reduces the risk of hypothermia and allows the newborn to retain their vernix caseosa for as long as possible — the whitish fatty layer covering the skin at birth. This layer maintains hydration, helps regulate body temperature, protects against pathogens and supports the development of the immune barrier.

At the first signs of a cold, you can clear your baby's nose with saline solution to prevent ENT infections. Ask your doctor for advice on the best technique to use, depending on your child's age.

Sleep and outings

At night, our body regulates, regenerates and repairs itself. It produces antibodies and activates its natural defences. Taking care of your sleep — and your child's — means taking care of both your immune system and your baby's.

Time spent in nature encourages a more diverse microbiome and helps reduce stress. Chronic stress weakens the immune system. So do not hesitate to go out regularly with your baby — to the forest, by the water, or even to a nearby park. 

Food supplements do not replace a varied, balanced diet and a healthy lifestyle, but they may support your baby's immune system.

The most recommended for immunity are:

• The vitamin D: for all infants, breastfed or not (recommendation of the French Society of Paediatrics)
• Probiotics: to help rebalance the microbiome, especially after a course of antibiotics, and to inhibit the growth of pathogenic bacteria
• Omega-3s: to help reduce the risk of allergies and inflammation
• Iron: only in cases of confirmed deficiency (on medical advice)
• GSE (grapefruit seed extract): antiviral, antibacterial, antifungal, antioxidant

And for the mother, Jolly Mama offers a full range of food supplements, including the post-partum supplement Post Essentials, which help you replenish your micronutrient stores with ease, as well as the breastfeeding food supplement moringa-based. 

A newborn does not need to live in a sterile environment — a gradual exposure to bacteria strengthens their immunity. That said, you can take precautions to limit risks in the very early days: ask those close to you to wash their hands thoroughly, wear a mask if they are unwell, and avoid kissing your little one on the face or hands (babies bring their hands to their mouths). 

Strengthening your baby's immunity relies on a balance between protection and exposure, supported by diet and lifestyle. By adopting the right habits from pregnancy and throughout the first months, you give them the best chances of growing up in good health. But do remember that every child is unique. A naturopath specialising in perinatal care can help you adopt the right habits for you and your baby.

⚠️ Important reminder

This article does not replace medical advice. If in doubt, always consult your doctor or paediatrician.