Back to school: children’s health

The beginning of a new school year is here and whilst for many it is a welcomed chance to return to some sort of normality and routine as the children head back to school, it often goes hand-in-hand with back-to-school germs, which in these times may be of particular worry to parents. In contrast to the summer months, which sees most children spending time outdoors, children tend to spend more time inside as the weather gets colder.

Classrooms can subsequently become breeding grounds for germs as they can hold many children in close proximity to each other and who may be sharing items and touching the same surfaces.  In addition, viruses can stay airborne longer when the temperature is colder. Although it is unlikely our children will completely avoid succumbing to cold and flu viruses throughout the year, as parents we can take measures to considerably lessen the frequency and severity of them falling ill.

Skip to Key Takeaways

Our immune system consists of cells and organs that help to protect us from an array of bacteria and viruses. A competent immune system will have the opportunity at various stages of bacterial or viral assault to prevent infection from taking hold, and at every stage there is a reliance on the presence of specific nutrients. In addition to this, our immune systems function at best when we have adequate sleep, manage our stress well and have sufficient exercise.

In these unprecedented times there maybe heightened tensions regarding health so the beginning of a new school year can make the perfect time to create a healthy routine and to implement some simple steps to help support your child and their immune system.

Provide them with a nutrient-rich diet

Aim to apply some basic principles to your child’s overall diet. Try to follow an anti-inflammatory diet, which includes a colourful and diverse range of whole foods, including plenty of fruit and vegetables, nuts and seeds, pulses and good quality protein (wild caught fish, grass-fed meat and organic free-range eggs and poultry). Attempt to remove or limit processed or sugary foods and drink as these are often high in sugar, refined carbohydrates, trans-fats and artificial ingredients. Children need nutrient dense diets to support growth, development and their immunity, but processed foods are usually devoid of nutrients and contain ingredients that promote inflammation. Highly processed foods can also deplete nutrients, meaning they take out of the body more than they put in!

Fruits and vegetables contain phytonutrients, which are natural chemicals produced by plants, and can help to protect us against inflammation. Healthy fats, such as omega-3 fatty acids (found in oily fish, walnuts, flax and chia seeds) can also help to dampen down inflammation. Chronic inflammation activates the immune system, which over time can exhaust it, leaving it less able to respond. This can then lessen the body’s ability to fight off infection.

Making a shopping list and planning family meals ahead of time can help to minimise the reliance on fast and convenient foods and sugary snacks when time is minimal. If your child has packed lunches aim to prepare the night before so there is no last-minute rush in the morning, which may affect preparation time and choice. Including your kids in the planning of their own lunch may help to ensure they will eat it!

Vitamin C

Vitamin C is perhaps the most well-known nutrient in relation to immune health and contributes to our immunity by stimulating and supporting numerous cellular functions of both the innate and adaptive immune system. It is a powerful antioxidant and therefore helps to protect the body from oxidative stress. The immune system can be particularly sensitive to the effects of oxidative stress, for example, the exposure of neutrophils (a type of white blood cell) to oxidants inhibits their motility. To protect themselves from oxidative damage, they accumulate millimolar concentrations of vitamins, resulting in improved cellular motility and subsequently, the enhanced killing of pathogens.1

Vitamin C supports the production of Natural Killer (NK) cells. NK cells are a type of lymphocyte and are able to kill cells that have been infected by a virus, making it is unable to replicate. This is crucial in preventing a virus from taking hold. Vitamin C also supports the production of antibodies, which are important for pathogen detection and inactivation.

Vitamin C promotes collagen synthesis and helps to protect cell membranes from damage caused by free radicals, thus supporting the integrity of the epithelial barriers. These are our first lines of defence against pathogens.

The body cannot produce vitamin C making it is an essential vitamin. It must therefore, be obtained regularly through the diet. Vitamin C is abundant in fruit and vegetables including citrus fruits, berries, spinach, cabbage and other leafy greens. Try including some fruit for breakfast, salad at lunch and vegetables with dinner to ensure sufficient intake for your child.

If you struggle to get your kids eating enough vitamin C rich foods, our delicious chewable orange flavoured gummy bears are suitable for children aged 3 years and upwards and contain 80mg of Vitamin C per gummy.

Vitamin D

Vitamin D is well-known for its powerful role in supporting healthy immune function. Many cells have vitamin D receptors that affect their function including immune cells, and as such, vitamin D strongly influences many aspects of health, including immunity. A deficiency in vitamin D is subsequently associated with an increased susceptibility to infection. For instance, research has shown that those with low Vitamin D levels are more likely to develop upper respiratory tract infections (URTIs) than those with adequate levels.1,2 Further studies have demonstrated an association of lower Vitamin D levels and increased rates of influenza.3

The best way of obtaining vitamin D is through the skin’s exposure to sunlight. Subsequently, as children begin spending more time indoors, vitamin D levels naturally drop. It is estimated that 16% of children in the UK will be deficient in vitamin D4 and this can be due to many factors, such as the weather, northern latitude, diet and lifestyle. Recently, there has been a potentially greater risk of deficiency as many of us have been confined indoors during lockdown, particularly if self-isolating.

The Recommended Nutrient Intake (RNI) proposed by SACN for all children aged 4 and above is 10 µg/day and Public Health England now recommend that all children supplement with this daily, particularly between October and March. Vitamin D is naturally present in very few foods but can be found in oily fish and small amounts in liver, mushrooms, butter, fortified foods and eggs, so including these can help give your children a boost. An average Western diet however, is likely providing a daily intake of only 3μg of vitamin D.

Our junior vitamin D3 is now available and includes a lower dose of 25μg, which is suitable for adults and children over the age of 8. If your child is not keen on taking tablets, try vitamin D3 in the form of drops, which can easily be added to your child’s drink and is suitable for all ages.


Selenium is an essential trace mineral and sufficient levels are vital for the effective functioning of the immune system. Selenium is involved in regulating oxidative stress, redox and other crucial cellular processes in nearly all tissues and cell types, including those involved in immune responses.1 In the UK, the selenium content of the soil is generally low and in the majority of age groups in the UK, the reported mean selenium intake is below the RNI.2 Excellent sources of selenium include brazil nuts, fish, beef and chicken, eggs and mushrooms.


Zinc is a trace element that is essential for a healthy immune system. It is especially involved in many aspects of immune function, with inadequate levels leaving you more susceptible to infection and illness. There is now an abundance of evidence that has accumulated which demonstrates the activity of zinc against a variety of viruses, and via numerous mechanisms. Good food sources of zinc to incorporate in to your child’s diet include beef, chicken, tofu, nuts, seeds, lentils, yoghurt and mushrooms.

Our Junior Immune Support is available for children aged five and over and includes 1-3 1-6 beta glucan along with vitamin C, iron, selenium and zinc, which contribute to the normal function of the immune system.

Support their gut

Maintaining a diverse microbiome is a vital part of immune health. The gut microbiome comprises trillions of bacteria, and a balance of good to bad is important to sustaining health. Gut dysbiosis indicates an imbalance of bacteria and can lead to intestinal permeability or ‘leaky gut’. This allows toxins to enter the bloodstream, which can trigger an immune response and dysregulate the immune system, causing inflammation and affecting how it may deal with infection.

Approximately 70% of our immune system resides in the gut, with colonies of commensal bacteria making up our first line of defence against ingested pathogens. If our protective barrier of friendly bacteria isn’t strong enough then we are more susceptible to viral or bacterial assault. Friendly bacteria can perform valuable functions in the body, for example, the bacteria in our gut help to produce vitamins, including a large proportion of our B6 requirements, which is important for our immune system.

Our children’s microbiome can be adversely affected by many factors, including sugary foods and drinks, processed foods, antibiotics and even stress. The microbiome is therefore largely a product of diet, lifestyle and environment and is consequently malleable, particularly in childhood.

Nurturing our children’s microbiome therefore, doesn’t have to be complicated and maintaining the right balance of bacteria in their gut can be achieved in many ways. Including fermented foods is one way of introducing probiotics in to your child’s diet. Probiotics are live microorganisms and have been shown to promote a healthy balance of gut bacteria. Try including foods such as kefir, sauerkraut, kimchi, tempeh or cultured yoghurt. Many yoghurts aimed at children are loaded with sugar, so be careful to avoid these.

Prebiotics are also important to include in the diet. These are indigestible fibres that help to increase and drive the growth of friendly bacteria. Short-chain fatty acids are largely produced from prebiotic dietary fibres and have many important roles in the body. For example, they are used as a source of ATP by the cells of the intestinal epithelium and act as a link between the microbiota and the immune system by modulating different aspects of the epithelium and leukocytes development and function.1

Ensuring our children are eating more fibre in general can therefore help to support gut and immune health. Some foods that are especially beneficial at feeding the good bacteria include, Jerusalem artichoke, asparagus, bananas, onions, garlic, leeks, fennel, cauliflower and broccoli. Taking a live bacteria supplement can also help to increase the beneficial bacteria in the gut.

Encourage them to play outside

Gut Health – Playing outside is beneficial for many reasons, including supporting gut health. All parents naturally want to shield their children from illnesses caused by bacteria, but by over-sanitising everything we also decrease their contact with the beneficial bacteria they need to support a healthy immune system. Interestingly, numerous studies have found that mice raised in sterile, germ-free environments have inadequately developed immune systems. Being in the garden, or even visiting the park, exposes children to the bacteria from the dirt and soil, which can provide exposure to organisms that can provide a positive stress on their immune system, keeping it activated, alert and primed.

Exercise – Playing outside goes hand-in-hand with exercise, and this is really important for immunity. There is now a wealth of media devices and computer games and many children rely heavily on these for entertainment. A report by the ‘Association of Play Industries’ revealed that children have never moved so little and points to substantial evidence that screens are a key reason. In fact, by the age of eight, the average child will have spent one full year sitting in front of a screen.1 In addition, the recent lockdown is likely to have exacerbated this. It is of no surprise therefore that official statistics published by the NHS this year show that 20% of year 6 children were classified as obese and that only 47% of children and young people were meeting the current physical activity guidelines.2

 Just as diet plays an important part in determining good health, exercise also contributes to good health and a subsequent healthy immune system. Immunosurveillance, is a term used to explain the processes by which immune system cells search, and identify foreign pathogens, such as bacteria and viruses. It has been demonstrated that acute exercise sessions can promote immunosurveillance.3,4 Exercise supports circulation and increases blood and lymph flow and subsequently increases the circulation of immune cells, allowing them to move through the body efficiently at a greater rate and in greater numbers. This is bad news for pathogens!

In a 2019 scientific review it was found that exercise helped to improve the immune response and lower the risk of illness.5 A further study showed that that those who did exercise five or more days of the week had lower numbers of URTI’s by over 40%.

Keep them hydrated

Ensuring your child is well hydrated is another important step for creating a healthy immune system. Adequate hydration contributes to a moist mucosa, which is vital for defending the body against pathogens – it is also a requirement for commensal bacteria to thrive. Our immune system is extremely reliant on the nutrients in our bloodstream, which requires water. Without adequate water we are not able to efficiently transport nutrients to cells of the immune system. Sufficient water intake is also essential for our detoxification pathways, which are required for eliminating waste products. Dehydration can contribute to digestive issues, which can also affect the absorption of immune loving nutrients!

Help them to manage their stress

Children react to stressors in just the same way as we do i.e. by producing the stress hormones adrenaline and cortisol. If these are raised over long periods of time, it can negatively impact on their immune system and eventually suppress it, leaving them vulnerable to infection. Excessive amounts of stress can be especially damaging in children as many vital stress regulatory systems, such as the brain and nervous systems are still developing.

When we perceive a stressful situation, the hypothalamus initiates the ‘fight or flight’ response. This is a primal evolutionary response to help us to survive and is meant primarily for short-term stressors. The stress response is however, largely inappropriate in today’s world of chronic stress. Modern stressors can be frequent and long-lasting, meaning the survival traits of the stress response (i.e. increased heart rate) are not effective in resolving the threat, and overtime can affect immunity. Studies have shown that the plasma concentration of noradrenaline, for example, has an inverse relationship with the immune function of phagocytes and lymphocytes.1 Digestion can also become impaired, often resulting in insufficient nutrients being delivered to the body, including ones that are important for immunity. Stress can also have a knock-on effect on sleep, and equally, poor sleep can also increase stress.

We are living in unprecedented times and disruptions to our children’s routines, their social activities, and their home and school life may have caused heightened levels of stress. Encouraging time spent outdoors and in nature and limiting the amount of time spent on a screen can be beneficial. There are many reports now that show negative consequences of too much screen time in children, ranging from anxiety, depression, obesity, sleep disorders, disconnection, impaired cognitive ability, social media distortion etc. Creative activities such as drawing or painting can provide an outlet for stress, as can exercise, so encouraging these can be useful. Children’s meditation, mindfulness and yoga are becoming increasingly popular and have been shown to boost immunity and help with stress.

When we are stressed, the metabolism of our cells increases and we burn through a lot more of the nutrients we normally need. The adrenal glands will be working hard to produce stress hormones, so including plenty of foods to support, enhance and regulate the adrenal glands can be beneficial. The B vitamins are important fuel for the adrenal glands, in particular, pantothenic acid (B5) and B6. Vitamins B5 and B6 are co-factors in energy production and many of the enzymatic pathways in the adrenal cascade. Good sources include fish, chicken, eggs, tofu, beef, sweet potatoes and avocados.

Include plenty of vitamin C rich foods, as stress can quickly deplete vitamin C and the adrenal glands contain one of the highest concentrations of vitamin C in the body. Magnesium is involved in over 300 biochemical processes in our body and provides energy to the adrenal glands and can help to calm and relax the nervous system. It is also one of the most supportive minerals to include during times of stress and insufficient magnesium levels in the body can lead to a low tolerance of stress. Great magnesium-rich foods include pumpkin and sunflower seeds, fish, leafy green vegetables, avocado nuts, brown rice, wholegrains, fish and meat.

Herbal support can also help. Adaptogens are herbs that adapt to the individual needs of the body, and can help to support the adrenals. Ashwagandha is an herb that is used in Ayurvedic medicine to aid sleep and calmness. In a randomized, double-blind, placebo-controlled study, ashwagandha was shown to relieve mild stress and frustration.2

Stress can negatively affect blood sugar levels, so try to include plenty of protein and healthy fats in the diet to help to keep these stable. Inflammation in our body can be caused by the foods we eat and is perceived as a type of stress and therefore stimulates the production of cortisol. Some of the top foods for increasing inflammation are sugar, dairy, gluten and grain-fed meat. Following an anti-inflammatory diet can help to balance out the affects of stress on the body.

Promote a restful sleep

Sleep is one of the pillars of health and is a restorative process that is vital for the optimal functioning of the immune system.  We all know however, that children are usually not that great at going to bed! Prolonged periods of inadequate sleep though can have detrimental effects on the immune system. For example, sleep loss is thought to impair host defence mechanisms and impact susceptibility to viral and bacterial pathogens.1 The immune system releases cytokines during sleep, which are immunomodulating agents that form part of the body’s defence against pathogens. Cytokines support the communication between cells in immune responses and promote the drive of cells towards sites of infection and inflammation. Research demonstrates that lack of sleep has negative effects on the nocturnal secretion of cytokines2, meaning a decreased production will impact on the body’s ability to cope with illness.

In one study, subjects recorded their sleep duration for 2 weeks and then were quarantined for 2 weeks after being exposed to a rhinovirus (common cold). Those who slept seven hours or less were 3 times more likely to become infected than those who slept eight hours or more.3 Furthermore, another study of identical twins was carried out to evaluate their sleep and immune system performance. It was demonstrated that twins who had different sleep patterns showed differences in their immune system responses i.e. less sleep was associated with decreased immune responses to infections.4

We depend on the sufficient production of melatonin, the sleep hormone, to enable us to get off to sleep. Exposure to light however, suppresses the secretion of melatonin and can trick your body in to thinking it is daytime, this can throw the body’s circadian rhythm out of whack. Blue light in particular does so even more and this is the light that is emitted powerfully from hand-held devices. Blue light can be useful during the day as it can increase attention and mood, but can be disruptive before bed. The excess and ease of hand-held devices available now has dramatically increased our exposure to blue wavelengths at night. To help support your child, try and ensure that they are getting the recommended number of hours sleep per night for their age and try to minimise their exposure to phones, tablets, TV and computers 1-2 hours before their bedtime. If your child needs a nightlight try and use dim red lights as these are less likely to suppress melatonin production. There are now available blue-light-blocking glasses which may provide some benefits or try to change the type of light emitted from blue to red on their devices.

Magnesium is known as ‘nature’s tranquiliser’ and is one of the most abundant minerals on the planet. It can help you to feel calm and relaxed as it activates the parasympathetic nervous system, it also regulates melatonin. Magnesium is present in many foods although many of us are deficient due to poor soil quality and poor food choices. Aim to include magnesium rich foods such as nuts, seeds and green leafy vegetables and limit or avoid foods or drinks containing sugar or caffeine as they can cause hyperactivity and sleep problems in children. Natural food sources of melatonin include almonds, walnuts, cherries and bananas, so increasing the intake of these may help in the evening.

Following a regular relaxing bedtime routine can also help your child to prepare for sleep. Giving your child an Epsom bath can be beneficial and another way of boosting their magnesium levels, as the mineral is easily absorbed through the skin and can encourage a good night’s sleep, as well as helping them to de-stress. Try adding some lavender essential oil too.

Inadequate sleep further places a demand on the adrenal glands, which will become worn out and unable to respond to demand, so supporting the adrenals will also help with sleep.

Iron is another key nutrient for sleep and sleep disturbances have been associated with poor iron status. Iron rich foods include lentils, chick peas, pumpkin seeds, beef (grass fed if possible), baked potato skins, spinach and other leafy greens.

Limit their sugar intake

Aside from often having detrimental effects on children’s behaviour, mood and concentration, sugar can also impact on the immune system. Refined sugar has been shown to decrease the performance of white blood cells and increase inflammation. Phagocytes (neutrophils, monocytes and macrophages) are immune cells that help to protect the body by engulfing bacteria and viruses and destroying them. Research has shown however, that sugar can decrease phagocytic capabilities.1 Sugar can also lead to weight gain and obesity, which can create a chronic state of low-grade inflammation, which negatively impacts on the immune system over time.

Diets that are high in sugar and refined carbohydrate can often be lacking in fibre. Gut bacteria help to convert fibre into short-chain fatty acids, which have great benefits for health. Sugar also feeds the bad bacteria in the gut, giving rise to inflammation and immune dysfunction. Cutting out sugar and increasing fibre intake can help to reap the immune supporting benefits of the beneficial bacteria. Most processed foods will contain high amounts of hidden sugars so try to be mindful of this and focus on a wholefood anti-inflammatory diet.

The optimal functioning of the immune system is reliant on many factors, including proper nutrition, adequate sleep, stress management, gut health and moderate exercise. By implementing steps and paying attention to these areas you can really help to boost your child’s immune system and health in general.

Key Takeaways

  • Children react to stressors in just the same way as we do i.e. by producing the stress hormones adrenaline and cortisol
  • Research has shown that those with low Vitamin D levels are more likely to develop upper respiratory tract infections (URTIs) than those with adequate levels
  • Nurturing our children’s microbiome doesn’t have to be complicated and maintaining the right balance of bacteria in their gut can be achieved in many ways. Including fermented foods is one way of introducing probiotics in to your child’s diet
  • We depend on the sufficient production of melatonin, the sleep hormone, to enable us to get off to sleep. Exposure to light however, suppresses the secretion of melatonin and can trick your body in to thinking it is daytime, this can throw the body’s circadian rhythm out of whack. Blue light in particular does so even more and this is the light that is emitted powerfully from hand-held devices
  • The optimal functioning of the immune system is reliant on many factors, including proper nutrition, adequate sleep, stress management, gut health and moderate exercise. By implementing steps and paying attention to these areas you can really help to boost your child’s immune system and health in general
  • Aim to apply some basic principles to your child’s overall diet. Try to follow an anti-inflammatory diet, which includes a colourful and diverse range of whole foods, including plenty of fruit and vegetables, nuts and seeds, pulses and good quality protein (wild caught fish, grass-fed meat and organic free-range eggs and poultry)

If you have questions regarding the topics that have been raised, or any other health matters, please do contact me (Amanda) by phone or email at any time.
01684 310099

Amanda Williams and the Cytoplan Editorial Team


Vitamin C

  1. Carr, A. C. and Maggini, S. (2017) “Vitamin C and immune function,” Nutrients. MDPI AG. doi: 10.3390/nu9111211.

Vitamin D

  1. Jung, H. C. et al. (2018) “Vitamin D3 supplementation reduces the symptoms of upper respiratory tract infection during winter training in vitamin D-insufficient taekwondo athletes: A randomized controlled trial,” International Journal of Environmental Research and Public Health. MDPI AG, 15(9). doi: 10.3390/ijerph15092003.
  2. Martineau, A. R. et al. (2017) “Vitamin D supplementation to prevent acute respiratory tract infections: Systematic review and meta-analysis of individual participant data,” BMJ (Online). BMJ Publishing Group, 356. doi: 10.1136/bmj.i6583.
  3. Sundaram, M. E. and Coleman, L. A. (2012) “Vitamin D and influenza,” Advances in Nutrition. American Society for Nutrition, pp. 517–525. doi: 10.3945/an.112.002162.
  4. NHS (2020) [online] Available at: [Accessed 25th July 2010]


  1. Hoffmann, P. R. and Berry, M. J. (2008) “The influence of selenium on immune responses,” Molecular Nutrition and Food Research. NIH Public Access, pp. 1273–1280. doi: 10.1002/mnfr.200700330.

Support their Gut

  1. Corrêa-Oliveira, R. et al. (2016) “Regulation of immune cell function by short-chain fatty acids,” Clinical and Translational Immunology. John Wiley and Sons Inc., p. e73. doi: 10.1038/cti.2016.17.

Play Outside

  1. Sigman, A. (2015) A Movement for Movement Screen time, physical activity and sleep: a new integrated approach for children. Available at: (Accessed: August 8, 2020).
  2. NHS (2020) Statistics on Obesity, Physical Activity and Diet, England, 2020 [online] Available at: [Accessed 30th July 2020]
  3. Simpson, R. J., Kunz, H., Agha, N., & Graff, R. (2015). Exercise and the Regulation of Immune Functions. Progress in Molecular Biology and Translational Science, 135, 355–380.
  4. Campbell, J. P., & Turner, J. E. (2018). Debunking the myth of exercise-induced immune suppression: Redefining the impact of exercise on immunological health across the lifespan. In Frontiers in Immunology (Vol. 9, Issue APR, p. 648). Frontiers Media S.A.
  5. Nieman, D. C. and Wentz, L. M. (2019) “The compelling link between physical activity and the body’s defense system,” Journal of Sport and Health Science. Elsevier B.V., pp. 201–217. doi: 10.1016/j.jshs.2018.09.009.

Help them Manage their Stress

  1. Yaribeygi, H. et al. (2017) “The impact of stress on body function: A review,” EXCLI Journal. Leibniz Research Centre for Working Environment and Human Factors, pp. 1057–1072. doi: 10.17179/excli2017-480.
  2. Lopresti, A. L., Smith, S. J., Malvi, H., Kodgule, R., & Wane, D. (2019). An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: A randomized, double-blind, placebo-controlled study. Medicine (United States), 98(37).

Promote a Restful Sleep

  1. Sleep and host defenses: a review – PubMed (1997). Available at: (Accessed: August 4, 2020).
  2. Irwin, M. (2002). Effects of sleep and sleep loss on immunity and cytokines. Brain, Behavior, and Immunity, 16(5), 503–512.
  3. Cohen, S. et al. (2009) “Sleep habits and susceptibility to the common cold,” Archives of Internal Medicine. Arch Intern Med, 169(1), pp. 62–67. doi: 10.1001/archinternmed.2008.505.
  4. Transcriptional Signatures of Sleep Duration Discordance in Monozygotic Twins (2017). Available at: (Accessed: August 4, 2020).

Limit their Sugar Intake

  1. Myles, I. A. (2014). Fast food fever: Reviewing the impacts of the Western diet on immunity. In Nutrition Journal (Vol. 13, Issue 1, p. 61). BioMed Central Ltd.

Last updated on 3rd March 2021 by cytoffice


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