Immune health and how the B-team of vitamins support ageing

Our immune system is a complex piece of biological machinery that keeps illness at bay. As we age, our immune function may work less effectively. If we also have a poorer appetite, it can be harder to get all the nutrients we need for good health. This article explains how the B group of vitamins support immune function.

By Citro partner Vitable

Having good immune system function is partly down to genetics, partly nutrition and partly lifestyle habits.

The brutal biological fact is that our immune system function peaks when we hit puberty and progressively declines with age.

The thing all of us want to avoid is the inevitable poorer functioning of our immune health - it’s sometimes called immunosenescence – or inflammageing. It’s the reason why more older people succumb to viruses and disease.

Supporting good immune function as we age

A healthy, balanced diet with a variety of foods from the main food groups helps to keep our immune system working properly.

For some people - such as those with low appetite or poor quality diets - nutrients like protein and omega-3 fats, as well as various vitamins and minerals have key roles in supporting our immune systems.

Alongside eating healthier – or using supplements for an immunity boost – here are some other ways to strengthen your immune system:

Get enough sleep

Getting enough sleep helps your body fight off infection. It can be harder to maintain good sleep habits as we get older, so try these natural therapies for better sleep.


Make sure to find physical activity you enjoy, not only to support immune health but also mobility and strength


Taking a few minutes to centre yourself in the present can help lower your heart rate and blood pressure, as well as reduce anxiety. These also help support your immunity.

Why you need B complex for immune function

B complex, or the B group of vitamins, is made up of 8 water-soluble B vitamins that are important for various bodily processes.

Water-soluble vitamins cannot be stored in the body. This means that we need to regularly replenish our stores of B complex from the foods we eat, or from supplements.

A deficiency of vitamin B has also been found to affect immune system processes.

The B complex vitamins include the following:

B1 (Thiamine):

Thiamine is crucial for energy metabolism and is essential for the proper functioning of nerve cells. It is also involved in the breakdown of carbohydrates. It is rare to be deficient in thiamine, although alcoholics, people with Crohn disease, anorexia, and those undergoing kidney dialysis may be deficient. The symptoms of thiamine deficiency are headaches, nausea, fatigue, irritability, depression and abdominal discomfort.

Foods with B1: Eat fish, meat, wholewheat breads and fortified cereals and nutritional yeast (like Vegemite!).  Thiamin is rich in grain foods such as cereals, bread, biscuits and rice. In Australia, it is mandatory to enrich baking flour with thiamin

B2 (Riboflavin):

Riboflavin is necessary for the metabolism of fats, drugs, and steroids. It also plays a role in maintaining healthy skin, eyes, and nerve functions.

Foods with B2: Eat dairy products (such as milk, yoghurt and cheese), yeast extracts, eggs, wholewheat bread and fortified cereals.

B3 (Niacin):

Niacin is important for converting food into energy and is essential for maintaining healthy skin, digestive system, and nerve function.

Foods with B3: Eat meat, chicken, fish, nuts and yeast extracts.

B5 (Pantothenic Acid):

Pantothenic acid is involved in the synthesis of fatty acids and is crucial for the production of hormones and cholesterol.

Foods with B5: Eat liver, meats, milk, eggs, yeast, peanuts and legumes. Pantothenic acid is rich in dried shiitake mushrooms, sunflower seeds, whole-grains, liver, kidney and egg yolks.

B6 (Pyridoxine):

Pyridoxine is essential for brain development and function. It also plays a role in the formation of red blood cells and the metabolism of amino acids. Helps prevent conditions like anaemia, which is when the red blood cells become unhealthy and are unable to carry adequate oxygen throughout the body. Insufficient oxygen in the blood affects healthy immune system function.

Foods with B6: Eat meat, fish, wholewheat foods, nuts and vegetables. Pyridoxine is found in organ and muscle meats, chickpeas, tuna, salmon, potato and banana

B7 (Biotin):

Biotin is important for healthy hair, skin, and nails. It also plays a role in fatty acid synthesis and the breakdown of amino acids and carbohydrates. Biotin is a water-soluble vitamin that can provide unique support to the immune system. Studies show that biotin deficiency may be linked to immune cell function.

Foods with B7: Eat liver, cauliflower, peanuts, chicken, yeast and mushrooms. The biotin content of food can vary depending on the plant variety, processing and season. The rich sources include beef liver, egg, salmon, sunflower seeds, sweet potato and almonds.

B9 (Folic acid or Folate):

Folic acid is crucial for DNA synthesis, cell division, and the formation of red blood cells. It is particularly important during pregnancy for fetal development. It also plays a role to help regulate the immune system’s T cells which fight infections and other pathogens.

Foods with B9: Eat liver, legumes, wholewheat bread, cereals and leafy green vegetables.  

B12 (Cobalamin):

Vitamin B12 is essential for red blood cell production and neurological function. It also plays a role in DNA synthesis. B12 acts as an immunomodulator for cellular immunity. It also supports chemical processes which aid in general health and wellbeing, helping prevent health problems such as systemic and vascular inflammation.

Foods with B12: Eat fish, meat, poultry, eggs and dairy, along with fortified breakfast cereals and yeast products.  

In the event you don’t get enough of the B group of vitamins from your diet, try taking supplements to make sure you have the sufficient amount of B complex for immunity.

Other vitamins to support immunity

There is also supplementation, a daily health practice that is easy to maintain and personalise.

In order to fill in the gaps left behind by diet and to safely address concerns about adverse reactions to eating certain foods, taking supplements of immunity support vitamins is a sustainable option.

We’ve only talked about B vitamins for supporting immunity. In truth, there are more than 10 vitamins and minerals that can all contribute to immune strength, and all of them can be taken in the form of supplements.

Vitable Australia is a company that fulfils Australians growing need for vitamin and mineral supplements, and its naturopath and specialists also list the following minerals and vitamins to support immunity:


Zinc is not naturally produced by the body, which means we do have to consume it in food or through immunity support vitamins. This mineral is found primarily in animal meats and shellfish, but it can also be found in vegetarian-friendly sources like beans and yoghurt.


Iron is needed for the rapid increase of all cells in our body, this includes those in the immune system. You can find iron mostly in red meats but it’s also present in poultry, sardines, mussels, beans, broccoli, and kale.  The role of iron in our bodies extends to supporting the immune system as it protects us from illness hence ensuring that it maintains this function for the entirety of our lives.

Vitamin C

This is the go-to vitamin for immunity, but vitamin C-rich foods may exacerbate existing health conditions. For example, citrus fruits can make acid reflux worse, or some Vitamin C-dense veggies can cause bloating or indigestion.

Vitamin D

Vitamin D comes from both food sources like salmon and tuna plus other Vitamin D-fortified foods, as well as healthy sun exposure. However, with Australia being a country of four seasons and with the concerns of maintaining a healthy diet as explained above, it’s easy to see how an immunity-related Vitamin D deficiency can be a common concern for Australians. Vitamin D supplements help maintain healthy immune system function in case of a lack of sun exposure or dietary deficiencies.

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Always read the label. Follow the directions for use. If symptoms persist, talk to your health professional. Vitamin and/or mineral supplements should not replace a balanced diet. The information on this page is general information and should not be used to diagnose or treat a health problem or disease. Do not use the information found on this page as a substitute for professional health care advice. The Vitable quiz is not intended to diagnose, treat, cure or prevent any disease. Terms and Conditions apply. When using this discount you will be signed up to a monthly flexible subscription. Edit or cancel at any time in your online account. Offer available for first-time customers only. T&Cs apply. This offer cannot be used in conjunction with another offer.  By using the discount, you will enter a flexible subscription: edit or cancel at any time."


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