7 Top Nutrients to Support Your Immune Health

 

It’s safe to say that caring for your immune health has become a top prority for many of us in recent times. Fortunately, there’s a lot we can do to give our immune system a helping hand.

Your immunity is an intricate and complex defence system standing between you and infection and protecting you from harmful pathogens constantly. When it comes to your immune health, it’s best to think of it as a system rather than a single entity. There are many players at work and rather than ‘boosting’, this system requires ‘balance’ to function optimally. To achieve this balance, your immune system does require some support and by creating the right environment through nutrition, physical activity, stress management, adequate sleep and clever supplementation, you can provide the immune system with what it needs to do its job well.

Paying close attention to key nutrients can be a great starting point. Read on for our top tips on some of the key nutrients your immune system needs to perform:

Vitamin C

Everyone's favourite immune vitamin and for good reason! Vitamin C often tops the chart for supporting your body in fighting infection thanks to it’s powerful antioxidant and anti-inflammatory activity. On top of scavenging harmful ‘free radicals’, which damage your body's tissues when left unchecked, Vitamin C is also known for supporting a healthy stress response. This is an important factor, as stress can really hinder your immune system’s capabilities. 

Thankfully, this micronutrient is widely available in the fresh foods we eat, such as kiwi, citrus fruits, bell peppers, berries, tomatoes as well as rosehips. Whilst we should absolutely focus on getting plenty of vegetables and fruits in our diets to meet the level of vitamin C we require for optimal health, studies(1) also suggest that supplementing with this essential nutrient upon the onset of an infection can help to speed up recovery and reduce symptoms. 

Vitamin D3 

Also known as the Sunshine Nutrient, Vitamin D3 is vital to your defence mechanisms as well as balancing immune response(2). Unlike most essential nutrients however, you can’t rely on food to keep your levels optimal. Most of our vitamin D comes from sunlight, so there is often a clear variation in seasons with lower levels during winter, which may well be one of the reasons we see an increased risk of colds and flu during these months. 

In fact, due to our global location, it is estimated that 1 in 5 of us in the UK have insufficient blood levels of Vitamin D for good health. Now factor in our lifestyles, which tend to see us more in our homes and offices and less outdoors than ever before, it’s not surprising that supplementing Vitamin D is now recommended by the Department of Health. 

When it comes to choosing a supplement, it's important to know which form of Vitamin D to choose. When your skin is exposed to sunlight, it produces Vitamin D3 and studies have shown that taking the supplement in this form leads to a higher contribution to the body’s vitamin D stores. Including foods with vitamin D also adds to your total intake, so should always be considered on top of getting enough sunlight and supplementation. The best sources include whole-fat dairy products, eggs, seafood and mushrooms. 

Zinc 

A well studied mineral, zinc is essential in playing multiple roles in the body and found in almost every cell. However, even a mild deficiency in this nutrient has been shown to have a negative impact on the immune system and how it deals with infection(3). The body isn’t great at storing zinc, and because it is needed for so many functions, it’s crucial we keep our zinc levels topped up on a daily basis. Food sources of zinc tend to be our protein based foods such as shellfish, meat, tofu, full-fat yogurt, lentils and seeds like pumpkin and sesame. Many immune complexes include zinc, which can be helpful with reducing the severity of infection, however be cautious with long-term supplementation. Zinc competes with copper for absorption in the body and therefore excess zinc can cause copper deficiency and vice versa. 

Glutamine 

An underrated and often overlooked nutrient in terms of immune health, however Glutamine is incredibly important. Bone broths in particular are loaded with this healing amino acid, which for generations has been a tonic for supporting our immunity. Amino acids, which make up proteins, are essential when fighting infection, but Glutamine notably plays a part in neural function, intestinal function as well as keeping our immune system healthy. The immune system is an energy hungry one and glutamine provides crucial fuel. 

Creating immune cells is key to dealing with pathogens and some key players, including lymphocytes and natural killer cells, need glutamine for normal cell production and proliferation. Protein is often known as ‘the building blocks of life’ and it’s true. We need these crucial amino acids to help repair and heal post-infection too. What makes glutamine exciting though is the potential for supporting our gut’s function as a physical barrier to infection(4). We know that a large proportion of our immune system is actually in our gut and therefore supporting gut resilience is vital in immunity. 

Vitamin A

Vitamin A is definitely a lesser known nutrient for immune health but absolutely vital and many people are often not paying close enough attention to this in their diet. Known to have anti-inflammatory effects, this nutrient is also critical in ‘regulating’ or ‘balancing' our immune response(5). Vitamin A is found in the diet in two forms: retinol, or ‘active vitamin A’ (found in high fat animal foods such as liver, eggs and grass-fed dairy products) and beta-carotene (found mainly in orange plant foods such as squash, sweet potato and carrots). Beta-carotene does need to be converted in the body however, and for some people this can be limited, creating lower levels of available vitamin A overall. 

Supplementing this vitamin isn’t quite straightforward either. Too much vitamin A can be damaging, therefore caution should be taken with long term supplementation and looking to increase foods rich in vitamin A is potentially a better option. 

Monolaurin 

A great addition to your immune toolkit could also be a natural compound called monolaurin. Made up of glycerol and the saturated fatty acid lauric acid, monolaurin often receives less attention than many other immune-helpers yet can be incredibly helpful in supporting the body to deal with viral and bacterial pathogens. Both lauric acid and monolaurin are found in coconut oil and human breast milk and have been found to have some significant antimicrobial activity, but importantly, without negative effects on the body(6). 

Phytonutreints & Botanicals 

The unsung heroes of immunity - we are learning more and more about plant chemicals or ‘phytonutrients’ and the research is pretty exciting. Thanks to the role these compounds play in strengthening their own plant’s immune system, we also benefit when we ingest them. Phytonutrients give the plant it’s colour, taste or smell and often protect the plant from threats in their natural environment such as disease and excessive sun.

Key phytonutrients such as Curcumin found in turmeric, Quercetin found in onions and Resveratrol found in berries and cocoa, have been researched thanks to their powerful immune-supportive actions. 

Curcumin is best known for its widespread anti-inflammatory and antioxidant activity. It also may function indirectly by enhancing the production of glutathione, known as the body’s master antioxidant(7).  Absorption can be a problem however, but simply by eating or drinking it with a source of fat and a pinch of black pepper gives remarkable improvements in digestive uptake, so make sure you add these when consuming turmeric. 

Curcumin has long played an important role in ancient healing remedies such as replenishing Ayurvedic golden milk. We have known instinctively to use plants to support our immune system for thousands of years, yet only now is the science catching up.

Quercetin has had its moment in the spotlight in recent years thanks to its potential for supporting the treatment of severe inflammation caused by viral infection(8). Quercetin is a plant pigment found in onions, red wine, apples, berries and green tea. It also has strong anti-viral properties. However one of the major benefits of taking quercetin alongside our other immune hero, zinc,  is that the quercetin is believed to ‘push’ the zinc into the centre of the cell where the mineral may then stop the virus from replicating. 

Resveratrol became more well known when studies emerged around it’s link to red wine consumption and health benefits  - no surprises why! Yet resveratrol is also in other popular foods we love to consume, cocoa and dark chocolate being top of the list. Benefits for the immune system seem to indicate a modulatory effect(9). Research also supports a protective role of resveratrol in respiratory disease as an anti-inflammatory and antioxidant agent. 

The balanced approach

When it comes to immune health, there is no such thing as a magic bullet. However it is important to provide the body with what it needs to handle the ongoing interaction with the outside world. Supporting immune resilience starts with a varied diet, rich in natural and brightly coloured wholefoods and then adding in targeted immune support compounds where needed. Let’s not also forget the importance of regularly getting a good night’s sleep, taking steps to combat stress and move our bodies. 

 

 

References: 

1. Hemila H, Chalker E. Vitamin C for preventing the common cold. Cochrane Database Systematic Review. 2013 Jan 31 (1)
2.  Telcian et al. Vitamin D increases the antiviral activity of bronchial epithelial cells in vitro. Antiviral Res. 2017; 137; 93-101.
3. Black RE. Zinc deficiency, infectious disease and mortality in the developing world. J Nutr 2003; 133: 1485S-9S
4. Kim MH et al. The Role of Glutamine in the Intestine and Its Implication IN Intestinal Diseases. Int Jr Mol Sci. 2017; 18(5); 1051.
5. Huang Z, Liu Y, et al. Role of vitamin A in the immune system. Journal of Clinical Medicine, 2018, 7(9), 258.
6. Schlievert PM, Kilgore SH, et al. Glycerol monolaurate contributes to the antimicrobial and anti-inflammatory activity of human milk. Scientific Reports 9, Article number: 14550 (2019)
7. Jagetia G et al. ‘Spicing up’ of the Immune System by Curcumin. Jr Clin Imm. 2007; 27;19(35).
8. Chen IY, Moriyama M, et al. Severe acute respiratory syndrome coronavirus viroporin 3a activates the NLRP3 inflammasome. Front Microbiol. 2019; 10: 50. 
9. Malaguarnera, L. et al. Influence of Resveratrol on the Immune Response. Nutrients.2019