Vitamin D3 + K2
The National Health Service in the UK recommends that every adult take a vitamin D supplement from October to April, when the days are shorter and we aren’t able to get sufficient vitamin D from sunlight.
Getting enough vitamin D is particularly important during flu season, as it can help reduce the risk of illness. Evidence from scientific studies suggests that vitamin D may help lower your risk of becoming ill with acute respiratory illnesses and the flu.
Therefore, people who are clinically vulnerable could benefit from taking a vitamin D supplement to increase the concentration of it in the blood. Researchers have also noted that supplementing with vitamin D could decrease the risk of serious infection and death.  They recommend taking vitamin K2 along with vitamin D to prevent negative, long term health effects.
Mushrooms are fungi and thrive in hostile ecological environments. Within the decay in which they grow, they encounter harmful pathogens, such as viruses and bacteria, much more often than other life forms.
Their survival depends on their resilient immune systems, and the features of their immune system that make them so resilient is also what makes them valuable to our immune systems as humans.
For example, the polysaccharide compounds in mushrooms such as the chaga mushroom and shiitake mushroom help to support healthy immune function.  They have been shown to have anti-viral, antifungal and antibacterial properties, as well as anti-tumour activity.  They also help to control blood sugar levels and reduce inflammation within the body.
The polysaccharides, terpenoids, sterols, and lipid compounds have all exhibited immune-boosting, cholesterol-lowering and anti-cancer effects. 
This is a robust probiotic containing a ‘good’ bacteria, bacillus coagulans, which may help prevent the growth of 'bad' bacteria and viruses in the body.
It is resistant to the acidic conditions found in the stomach, and forms spores that multiply in the intestine, produce the L(+) form of lactic acid and prevent the growth of pathogens. This can help prevent an upset stomach and has been shown to ease symptoms of Irritable Bowel Syndrome  and intestinal gas-related symptoms, such as flatulence and bloating. 
A very small study of 10 people also showed that bacillus coagulans helped strengthen immune response to certain viruses in the body. 
Broccoli Sprout Extract
Broccoli sprouts are rich in antioxidants and can contain as much as 50 times the sulforaphane found in mature broccoli. This means that in one ounce of broccoli sprouts, you get as much antioxidant as you would in three pounds of fully grown broccoli.
Studies have shown that sulforaphane in broccoli seeds demonstrates antiviral activity and can be effective against the Influenza A virus.  There is also scientific evidence to suggest that NRF2 in sulforaphane (nuclear factor erythroid 2 p45-related factor 2) may help reduce inflammation caused when the body has an extreme immune response to viruses that cause acute respiratory illness. 
Other studies show that sulforaphane helps kills H. pylori bacteria, which can cause gastritis, stomach ulcers, and in some cases lead to stomach cancer.
As well as being a source of dietary fibre that helps maintain good digestive health, green smoothies that include ‘superfoods’ such as kale, spinach, and spirulina are packed full of vitamins and minerals. A high-quality, organic greens drink can therefore be a great way to detox, increase your energy levels, offer your body additional immune support and improve your general well-being.
Green vegetables such as spinach and kale are rich in quercetin, a pigment belonging to a group of natural plant chemicals (phytonutrients) called flavonoids. Studies have shown that quercetin has antiviral properties that can inhibit virus enzymes that are essential for virus replication and infection.  It could therefore help prevent or decrease the severity of viral infections.
Since sourcing the ideal ingredients for a nutrient-rich greens drink can be costly and time-consuming, an organic greens drink powder is a quick and convenient alternative. You simply add a scoop to cold water, milk, yogurt or your favourite beverage, and enjoy.
Vitamin C deficiency is quite common, with studies suggesting that as much as 34% of men and 27% of women aren’t getting enough, particularly in the older age groups and people suffering from chronic illnesses.
As is widely known, vitamin C plays an important role in maintaining normal immune function. It helps aid the production of white blood cells, which help protect the body against pathogens such as harmful bacteria and viruses that enter the body. 
As a potent antioxidant, vitamin C helps protect white blood cells from damage caused by harmful free radicals, and helps them to function more effectively.
Vitamin C also helps strengthen the body’s most important barrier to infection: the skin.  Studies have shown that taking a vitamin C supplement may speed up the time it takes a wound to heal.  
Zinc is an essential mineral when it comes to maintaining a healthy immune system, so it’s worrying that studies show that nearly a third of older adults are deficient in zinc. 
Zinc deficiency can have a significant impact on immune function and increases the risk of infection and illnesses such as pneumonia.   This is because it plays a vital role in the development of and communication between immune cells, such as macrophages, neutrophils, phagocytes and cytokines.
Scientific evidence suggests that taking a zinc supplement may help protect against viral infections such as colds. It could also help to start taking zinc even if you’re already ill, as it may help you recover more quickly from a cold.  
When taking zinc it is vitally important you pair it with copper as zinc reduces the amount of copper your body absorbs. High doses of zinc can actually cause a copper deficiency, which can cause health issues.
Always consult a doctor and/or a pharmacist to find out how much zinc to take each day.
Supplements to support a healthy immune system
If you’re looking for supplements that will help support and maintain a healthy immune system, but aren’t sure which ones to choose, we have a range of immunity supplements (including bundles) for you to choose from.
See our immunity booster supplements to find out more.