1. Vitamin C 

Vitamin C is the essential vitamin that helps strengthen the immune system. "Vitamin C fights free radicals and encourages the production and efficacy of white blood cells that help protect the body against infection, and it appears to reduce the severity of colds and recovery time by 8% in adults and 14% in children," says Emma. It promotes the production of antibodies - proteins that are produced by the body when it detects something harmful - that help target and neutralise foreign invaders. Vitamin C is also a potent antioxidant, meaning it helps get rid of pesky free radicals (unstable molecules that can damage cells). This helps protect immune cells from oxidative stress and damage, ensuring they function optimally 

How to add it to your diet:

Because of vitamin C’s amazing potential to support immunity, we call it a 'powerful protector' at Leapfrog Remedies. That’s why it became a vital ingredient of our best-selling product, Leapfrog IMMUNE. Getting more Vitamin C into your diet is also easy through fruit and vegetables: try adding in guavas, bell peppers, oranges, broccoli, strawberries and kale. Did you know that kiwi is the fruit with the highest Vitamin C content, with almost twice the amount of an orange? 

2. Zinc

This mighty mineral is an immunity-boosting powerhouse that combats colds and fights inflammation, all while creating new cells and helping us process food efficiently. It assists in wound healing, and helps to balance hormones, boost energy and acts as an antioxidant and anti-inflammatory. Several good reasons why it made the cut in our Leapfrog IMMUNE. "Zinc may effectively reduce inflammation, boost immune health, reduce your risk of age-related diseases, speed wound healing, and it plays a key role in childhood development" says Emma, "It affects how our cells respond to infections and activates enzymes that break down proteins in viruses and bacteria." 

A deficiency of zinc can mean that you are more susceptible to a variety of pathogens. Lack of zinc in the diet has been shown to lead to low levels of B-cells and antibodies. 

How to add it to your diet:

A key micronutrient and trace element that our bodies can’t make or store, we need to source zinc from foods. Zinc is easily found in many foods, including meat, fish, eggs, nuts, legumes, dairy and whole grains. A sprinkling of pumpkins seeds will do the trick, but if you’re looking for zinc supplements you’ll find 5mg in every tablet of Leapfrog IMMUNE. A study from 2020 published in the Journal of Nutrition showed that zinc supplementation could reduce cold duration by 2.25 days. 

3. Mushrooms

Mushrooms, particularly certain types like shiitake, turkey tail, reishi, and chaga, have been found to support the immune system in various ways, potentially helping the body fend off colds and coughs. "Mushrooms are rich in beta-glucans, a type of polysaccharide that helps activate the immune system," says Emma "These compounds can enhance the body's ability to recognise and fight off pathogens, such as viruses and bacteria, which are responsible for colds and respiratory infections. Also, inflammation plays a significant role in the symptoms of colds, such as a sore throat, runny nose, and congestion. Many medicinal mushrooms have anti-inflammatory effects."

How to add it to your diet:

Medicinal mushrooms come in powder form, so add a spoonful to your favourite recipes, or try a cup of warming mushroom tea, full of that natural "umami" flavour. Sauté more common mushrooms with olive oil garlic and herbs and add as a topping to pasta, pizza, meats or eggs. Slice them to add to soups and stews or simply eat raw button mushrooms in a salad. 

4. Omega-3 

We don’t eat enough Omega-3s and the essential fatty acids that they contain are very important. "We can’t produce them ourselves," says Emma, “and we need at least 3 – 4 portions of oily fish per week. Omega-3 is anti-inflammatory which means it can have benefits for the hair, skin and hormones, but also combat inflammation from disease.”

How to add it to your diet:

"One of my staple lunches is sardines on toast – so cheap and so healthy! I fry it in a pan and eat on a piece of sourdough on toast," says Emma "You could also choose mackerel." Seeds are also high in Omega-3 so add those to your foods, such as salads or porridge, for a boost – pumpkin, sunflower, flax and hemp all do the job. You can always turn to supplements too for Omega-3. The ideal scenario is to eat oily fish at least twice a week, but if this isn’t possible, a supplement to turn to – that we love at Leapfrog – is Bare Biology. If you suffer from arthritis, depression, migraines, asthma, diabetes, cardiovascular disease, obesity, or any other chronic condition, then you may benefit from taking Omega 3 supplements, which come in capsule form or liquid drops. 

5. Probiotics

Gut health has become hallowed in the wellness world, and for good reason: a gut microbiome with a diverse array of “good bacteria” has a positive effect on our immune function, inflammation, allergies, metabolism, weight and appetite.

So, what can we feed our guts to populate it with good bacteria? Probiotics can help restore a healthy balance. Kefir, for example, is a natural fermented food that has 30 strains of probiotic bacteria and yeasts. If you drink kefir or kombucha or eat fermented foods like sauerkraut or kimchi, you can increase the number of bacteria in your diet by up 10 thousand times.

Not only excellent for supporting your immune system, studies show that taking probiotics daily can reduce the risk of developing allergies by up to 50%.

"70 to 80% of our immunity lies in the gut,” says Emma,"so we need excellent digestive health to stay in all-round physical health. Probiotics help to populate your intestine with beneficial bacteria to allow your microbiome to truly flourish. A happy gut means a stronger immune system."  

How to add it to your diet:

Given her Austrian heritage, Leapfrog's founder Stephanie likes to load up on sauerkraut. But if you're not keen on the taste, live yoghurt with fruit, nuts and seeds is great way to start each day.

6. Pigmented Fruits & Veg

"Aim to eat the colours of the rainbow for a potent antioxidant hit and to eat in season to vary your choices." says Emma "There is the added bonus that this helps feed our gut microbiome too. Dark or intensely pigmented fruits and veg have polyphenols that can support immunity." 

How to add it to your diet:

Raspberries, blackberries, red peppers, steamed kale, and pumpkins are all beneficial. Add the fruit to smoothies or porridge and the veg to soups or salads. “I'm not a fan of juicing as you lose the fibre of the fruit and consume high quantities of sugar, so smoothies are a much better option. And do consider throwing some leafy greens in too" says Emma. 

7. Bone Broth

Bone broth is rich in collagen and gelatine, which support gut health. "We want to protect our gut lining and prevent pathogens from entering the bloodstream. The amino acids in bone broth - like glycine - can help modulate the immune system by reducing inflammation and supporting the production of white blood cells, which are essential for fighting infections," says Emma. Bone broth is rich in essential minerals such as calcium, magnesium, phosphorus, and potassium, and is an excellent way to stay hydrated. Proper hydration is important for maintaining the mucous membranes in the respiratory and digestive tracts, which act as barriers against pathogens. Staying hydrated also helps the body detoxify and maintain overall health, supporting immune function.

How to add it to your diet:

Chicken bones can be simmered for several hours or it's easy to buy excellent ready-made and powdered options, for example from our friends at Freya.  

9. Vitamin D

Vitamin D has become quite an immunity-boosting star and for good reason. "Vitamin D has anti-inflammatory and immuno-regulatory effects and can enhance the function of immune cells called T cells and macrophages. It also plays a role in bone health, mood and muscle development, and keeps at bay a host of health issues including heart disease, cancer, dementia, autoimmune diseases and type 2 diabetes," says Emma.

"Vitamin D deficiency can lead to weakened immune system, so it’s important to supplement if you live somewhere where sunlight doesn’t provide adequate amounts of UVB rays."

If you can expose your skin to sun safely, then this is an excellent source of (free!) Vitamin D. Just 10-15 minutes of unprotected sun exposure allows our skin to synthesise the sun’s UVB rays from cholesterol into the Vitamin D, which is actually a steroid hormone rather than a vitamin. It's a good idea to get your Vitamin D levels checked regularly, says Emma.

How to add it to your diet:

It’s difficult to get enough vitamin D from foods. Cod liver oil does contain good amounts of Vitamin D3, but is too often contaminated with toxins, so Emma  tends not to recommend it unless carefully sourced. There is also some D3 in fatty fish like salmon, tuna, trout, mackerel, a little in beef liver and eggs too. Otherwise look for fortified foods, like breakfast cereals and spreads. It’s worth noting that Vitamin D needs Vitamin K2 to help metabolise calcium correctly. Vitamin  K2 from foods is also produced by good bacteria in the gut and is also vital for appropriate blood clotting. Emma suggests sourcing supplements that contain good amounts of both Vitamin D3 and K2.

Note that if you’re over 65 you generate a quarter of the Vitamin D that someone in their 20s does (combined with the fact that older adults are more likely to stay indoors for longer). As we age bone breakdown rates overtake bone building, particularly in menopausal women. Research has shown that Lactoferrin may reduce signals that promote bone loss and boost signals that promote bone growth.

A meta-analysis of clinical trials found that taking between 400 IU and 1000IU of Vitamin D each day for 12 months could reduce the risk of acute respiratory infections.

8. Lactoferrin

"Lactoferrin – the hero ingredient of Leapfrog IMMUNE – is a wonder protein that works as a vital part of the immune system to protect the body against viruses and bacteria. Lactoferrin can prevent infection in the first place, but also reduces the symptoms and shortens the duration of an infection if we do pick up a cold," says Emma. An antioxidant and anti-inflammatory, Lactoferrin is also good for gut health as it supports the growth of beneficial intestinal flora and kills off the bad bacteria, too.

Lactoferrin is found at the entry points of our bodies – in tears, mucus and saliva – and acts as our first defence against invading pathogens. It is also found in colostrum and breast milk and is key to building a baby’s immunity. Cow’s milk is biologically similar to human milk, and so is a useful source of lactoferrin for supplements.

Though lactoferrin is little-known, studies suggest that taking lactoferrin supplements may significantly reduce the risk of upper respiratory tract infections, as shown in this meta-analysis of clinical trials was written by Dr Hamid Merchant – Leapfrog’s pharmaceutical consultant – and his team at the University of Huddersfield. 

How to add it to your diet:

Can we drink or eat dairy to get the benefits? Though lactoferrin is found in milk, it is only found in small amounts – the mean concentration is around 100mg/litre. It can also be assumed that most of the lactoferrin in milk foods and drinks is denatured through the sterilisation and pasteurisation of dairy products.

Leapfrog’s lactoferrin is carefully extracted from grass-fed cows milk in order to preserve its biological activity so that it packs a punch in our immune supplement Leapfrog IMMUNE - a tablet of lactoferrin, zinc and vitamin C that we made chewable to increase its efficacy as its absorbed by the epithelial cells that line the mouth. It will supercharge your immune system in any season.