Boosting immunity is something that is on every parent's (or to be parent’s) mind right now. While there is no definitive research published on nutrients or herbs for the novel COVID-19 virus, there is a substantial amount of evidence supporting micronutrient (vitamin and mineral) adequacy, for ensuring optimal immune function and defence.
While supermarket shelves have been stripped of any supplement that hints of immune support, there is still a lot that can be done with food. Whole foods offer an abundance of beneficial nutrients including vitamin and minerals. The good news is, the stockpilers haven’t touched the fruits and vegetable aisle! It is hard to believe that the most nutrient dense foods are still in abundance in stores. There really is a lot that can be done with nutrition and lifestyle alone.
It’s normal to be feeling a little anxious, possibly stressed over the current COVID-19 situation. Don't forget that your little ones may be too. They overhear everything and pick up on your stress levels also.
Acute stress can not only lower immune function but can also increase inflammatory cytokines. Studies undertaken on children with high levels of early life stress show lifelong alterations in immune dysregulation and markers of inflammation.1
Do what you can to reduce your stress and, in turn, your children’s stress. I suggest limiting unnecessary news, doing activities that make you laugh and have lots of time for cuddles.
Get enough sleep
Adequate sleep assists in not only rest and recovery but also the strengthening of the immune function.2
Melatonin, a hormone secreted by the pineal gland which is responsible for the tired feeling people experience before sleep, is thought to play a protective role against COVID-19.3 Fortunately, pregnant women (especially in the third trimester) and babies have naturally high melatonin levels. Melatonin acts as an anti-inflammatory and has immunomodulating effects and has been proposed as a safe adjunct treatment for COVID-19 induced pneumonia, acute lung injury, and acute respiratory distress syndrome.
Limit blue light exposure from screens plus stick to a bedtime routine to ensure your child is getting enough restorative sleep to reap the benefits of naturally produced melatonin and strengthen your child’s immune system.
Support the health of mucosal membranes
There are a few key nutrients that are involved in the maintenance of mucosal membranes. Mucous membrane is what line the nose, oral cavity, throat, and gastrointestinal tract. These form the first line of immune defence against viral pathogens. There two key nutrients are zinc and vitamin A, which not only maintain the mucosal membrane layer but also collectively regulate cell division and are essential for a proliferative immune response.
1. Vitamin A
Vitamin A is essential for mucous membrane integrity.4 Vitamin A is essential for immune regulation, including regulation of natural killer cells, inflammatory processes, has antimicrobial effects, antioxidant actions as well as playing a role in adaptive immunity (antibody response).
Two types of vitamin A can be obtained through foods and supplements; beta-carotene (provitamin A) and retinol (preformed vitamin A). Retinol is the form that exerts immune supportive actions. Beta-carotene can be converted to retinol; the conversion can be slow and limited.
Vitamin A-rich foods include;
Retinol containing- animal livers, egg yolks, cod liver oil, fatty fish like herring or salmon.
Beta-carotene containing- pumpkin, carrots, spinach, rockmelon, apricots, mango, and tomatoes.
Zinc is essential for mucosal membrane integrity of the respiratory tract, (often the first line of immune defence), immune cell production and function, has antimicrobial effects, a role in inflammation regulation as well as antioxidant functions. Deficiency of zinc can predispose your child to an increased risk of infections. 4
The body does not store zinc,5 so zinc-rich foods should be consumed daily from 6 months and especially during pregnancy.
· Red meat (preferably organic)
· Canned oysters (safer than fresh, because of the risk of food poisoning)
· Organic dairy products
· Legumes (e.g. lentils and chickpeas)
· Organic eggs
· Nuts + seeds (if not allergic and butters for younger babies and children)
Support Gut Health
During the first 1000 days of life, your baby's gut microbiota or "microbiome" is developing. How your child was born, how they are fed, antibiotic exposures (including those in food supply), and many other factors impact their microbiome, and how their immune system matures.
Being a mucosal membrane, the gut acts as an anti-infective barrier. In addition to this, the gut hosts the body's largest population of immune cells, and the microbiota stimulates both innate (first line) and adaptive (immune memory) responses.
You can support your families gut and immune health by providing them with a variety of foods, including fruits, vegetables, whole grains, and legumes (e.g., lentils and beans).6 These foods contain fibre and are rich in prebiotics which support gut health. Prebiotics, galactooligosaccharides (GOS), and fructooligosaccharides (FOS) help to commensal microbiota (aka good bacteria) to thrive.
Probiotics, especially Lactobacillus and Bifidobacterium species are key regulators of gut mediated immunity.7 Be sure to include fermented foods such as yogurts, kefir and fermented vegetables to get your daily dose of good bacteria.
For my pregnant and breastfeeding ladies, I recommended supplementing with a mother and baby specific probiotics which contains Lactobacillus and Bifidobacterium strains which also help in the prevention of allergies, atopic conditions such as eczema.8 I recommend formula fed babies and those born via c-section also consider probiotic supplementation.
Eat an abundance of vegetables and fruit
Fruits and vegetables provide an abundance of essential nutrients. Vitamin C is a critical nutrient for optimal immunity.
Vitamin C accumulates in phagocytic cells, immune cells that eat invading pathogens. Vitamin C also plays a role in cleaning up at the site of infection and reduces potential tissue damage.9
Eating a diet rich in fruits and vegetables will supply adequate vitamin C to support your immune system. The fresher the foods, the better, as being a water-soluble vitamin, levels decline in foods each hour after picking. My top pick for vitamin C rich foods includes all berries, mango, cherry, kiwifruit, pineapple, and vegetables such as sweet potato, broccoli, spinach, and cauliflower.
During time of stress and when fighting off an infection, the bodies requirement for vitamin C increases. A Cochrane review10 of supplemental vitamin C found that prophylactic (preventative) supplementation with lower dosages didn’t reduce the instance of the common cold. Higher dose vitamin C when used acutely, did significantly reduced the duration of the common cold and alleviated symptoms. The review found that the effectiveness of vitamin C, is certainly dose dependant. If feeling run down, consider a vitamin C supplement to boost your levels and give your body the best chance of fighting off an infection.
Avoid Added Sugars
Humans used to have the ability to make our own vitamin C. Through our evolution, we have lost the ability to synthesise it, and vitamin C must be obtained through food.
Glucose is structurally similar to vitamin C and uses the same transport channel into our cells. When your child consumes added sugars (table sugar, sucrose or dextrose), their blood glucose levels rise. This increase in glucose concentration competes with optimal vitamin C absorption. Be sure to read labels and avoid added sugars.
Ensure adequate protein intake
Consuming adequate dietary protein is essential to provide amino acids to support the structural components of immune cells. While most babies and children easily meet their protein requirements, most pregnancy and breast-feeding women are falling short. Protein rich foods such as meats, poultry, eggs, fish and nuts and seeds also provide a dense source of many essential nutrients including zinc, vitamin A, selenium and vitamin B6.
B6 or pyridoxine, is a vitamin that doesn’t get much airtime when it comes of immunity, though it is probably one of the most important. Vitamin B6 deficiency is common among women of childbearing age,11 mainly because the contraceptive pill depletes it. Vitamin B6 deficiency can impair immune responsiveness AKA how quickly you respond to an invading pathogen. Think protein rich foods (meat, eggs, fish and soy) and wholegrains as your food sources of B6.
Get your daily dose of vitamin D
Vitamin D exerts antiviral, immunoregulatory actions .12 Vitamin D enhances cellular immunity, which in part reduces the inflammatory cytokine storm produced by the innate immune system. A Cochrane systemic review,13 reported that there were “several studies that reported an association between vitamin D deficiency and infections among children” below the age of five years.
Vitamin D is a fat-soluble vitamin that can be obtained from sunlight and food sources including fatty fish, egg yolks, dairy products as well as fortified foods.
Breast milk provides a complex of essential nutrients as well as a whole host of immune-boosting benefits; it is, unfortunately, a poor source of vitamin D. The America Academy of Paediatrics14 recommends that all exclusively breastfed babies be supplemented with 400iu of vitamin D daily. In Australia, mainly because of the abundance of sunshine, the recommendations for vitamin D supplementation only apply for exclusively breastfed infants with darker skin or of veiled mothers. Give the current situation of indoor confinement and lack of sun exposure, vitamin D supplementation for exclusively breastfed babies may be indicated. Formula-fed babies do not need to be supplemented with vitamin D as formulas are fortified with the correct daily dose.
There is a multitude of nutrients involved in supporting your family’s immune system, most of which can be easily obtained in sufficient amounts through a healthy balanced diet. No one nutrient is more important than another, in the absence of deficiency. If you know your diet is lacking, could be lacking due to increased demands (e.g. pregnancy, breastfeeding, growth in children, stress or fighting off an illness) or if you know you or your child are prone to certain deficiencies, you may like to consider supplementation.
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