Fears around coronavirus are rising – and there seems to be little we’re advised to do in-between washing our hands regularly, and self-isolating. But another way we can help put ourselves in the best position to avoid the virus – and any other cold and flu viruses – is through our diet.

Our immune system remains something of a mystery to scientists. But we do know that it’s a complex, interconnected system that incorporates many organs and functions.

The immune system consists of two parts. First, the innate immune system, which is what viruses first come up against when they invade our bodies. This system flushing out the invading cells, before the second system, the adaptive system, targets pathogens the body has already had contact with to create memory cells of new ones, so the body can fight them off if they dare to return in future.

This explains why most of us will only contract chicken pox once. Unfortunately for us, many viruses, such as flu viruses and the common cold, mutate and adapt, confusing memory cells and successful infecting us. Thankfully, both our lifestyle habits and diets are known to affect the strength of our immune systems via several mechanisms.

There is evidence to suggest that nutritional deficiencies can weaken our immune system and make us more vulnerable to infections. First – we need to make sure we’re eating enough; our immune systems need energy – and the right nutrients – to work to their potential.

Our immune systems need enough energy to make immune cells, which act as building blocks, and our enzymes, which need vitamins and minerals to work effectively. This means we need to make sure we’re eating all of our body’s requirements for macronutrients, vitamins and minerals, including vitamins C and D, as well as B6, B12 and folate, zinc, copper, iron and selenium, as well as essential amino and essential fatty acids.

Research has found that people who are deficient in one or more nutrients are generally more susceptible to infections, and these infections are more severe and last longer. And when given supplements to rebalance their deficiencies, people tend to see improvements in the functionality of their immune systems and they become more resistant to infections, and cope better if they get infected.

These nutrients are found in ample quantities in a diet rich in fruits and vegetables – but that diet must be diverse. The key to using our diet as a tool to make sure we’re fighting fit is to ensure we eat as many different types of nutrients and minerals as possible.

For those who think that strictly following a plant-based diet is enough, there are things to keep in mind. For example, it’s slightly harder to get iron, for example, and more difficult to get enough B12, in a diet without animal products. For these, and for omega 3 fatty acids, many experts recommend supplementation.

However, it’s recommended we get as much goodness as we can from food, rather than relying on supplementation, unless absolutely necessary. Some research has highlighted the risks of overdosing supplements, including increased risk of some cancers, and damage to the liver. Plus, food has added benefits supplements can’t supply us, such as fiber, which is associated with a whole range of health benefits, including lower risk of death, diabetes, heart disease and cancer.

While it’s reasonable to eat healthier coming into the cold season, it makes more sense to do this over the long-term. While some studies show that taking vitamin C and zinc supplements during cold can reduce its length and severity, eating a bad diet and then trying to self-medicate with a better one won’t be as effective as eating a healthy diet in the long term.

One of the best immune-boosting foods is fruit, due to their high content of polyphenols, especially flavonoids. Studies have found that eating fruit before exercise helps to reduce inflammation, oxidative stress and immune dysfunction in the body after exercise. Polyphenols are also found in nuts and vegetables, tea and coffee. But to maintain these benefits, there must be consistency, rather than a quick fix of smoothies and juices in the run-up to flu season.

In short, a healthy gut can help contribute to a strong immune system – and the key to a healthy gut is a healthy diet and fiber, which organisms in the colon feed off.

One of the ways you can stay fighting fit is to stock up on gut-friendly, polyphenol-rich, vitamin-full fruits and vegetables. Of course, this alone won’t prevent transmission of coronavirus or any other viruses, as we also need to stay vigilant with hand-washing and staying indoors when symptoms occur. But it’s one way we can ensure our immune system is best equipped to keep us healthy.