How to strengthen the immune system at the table?

Our health is constantly targeted by threats. Whether it is viruses, bacteria or whatever, fortunately we have effective defense weapons, among which our immune defenses stand out.

In some situations this weapon is physiologically lowered; for example, immune defenses in pregnancy are naturally lower. Then there is no shortage of cases when we feel the need to boost them, for example, when the cold weather arrives, bringing with it the classic seasonal ailments, but not only that: how many parents are looking for ways to boost their children's immune defenses to prevent them from spending more days at home, sick, than at school?

There is no shortage of solutions proposed to address this need. Often the advice is about what to eat to make our immune system work better. Let's try to understand which of these tips are valid and, therefore, how to strengthen the immune system at the table.

Not just superfood
Often what is recommended is to eat superfoods - foods that are considered particularly healthy, in this specific case because they boost the immune system. However, rather than focusing on the consumption of one or a few foods with seemingly miraculous properties, it would be better to take care of our diet across the board, focusing on the variety of ingredients we put on our plate and thenutritional balance of our diet.

In fact, avaried diet helps us to take in all the nutrients our immune system needs without any special imaginative efforts to organize our daily diet and without having to hunt for the expensive superfood that we have been guaranteed to be the best immune ally.

In short, before spending capital on goji berries, it is good to vary our choices at the table. For example, we can:

• Alternate consumption of pasta and rice with that of grain cereals such as spelt and barley, sources of fiber that nourishes the gut microbiota-an ally of our immune defenses;
• eat fruits and vegetables of different colors so that we take in as wide a variety of vitamins and minerals as possible, including those essential for the proper functioning of our immune system.

On the other hand, as far asnutritional balance is concerned, it is good to remember that carbohydrates are the main source of energy for our bodies and that without adequate energy at our disposal, it is difficult to think of being able to feel fit.

But an adequate supply of protein is also important: the antibodies we produce to fight viruses and bacteria are molecules that are protein in nature, and we cannot think of synthesizing them without the necessary source material to do so.

What about fats? Even when it comes to immune defenses, it is good not to lump all fats together, because different fats can have different effects on inflammatory processes, which are crucial phenomena within the immune response. This is also why we should follow the recommendation to limit consumption of saturated fat sources (such as meats and butter) in favor of greater consumption of unsaturated fat sources (such as fish and extra virgin olive oil).

Finally, as already mentioned, taking in all the vitamins and minerals we need ensures that we also fill up on those more specifically needed by our immune system.

Immune-boosting nutrients and foods
That said, some nutrients are particularly useful in promoting the proper functioning of the immune system. Because - mind you - the question we should be asking ourselves is just that: not so much how to boost immune defenses (a concept that from a scientific point of view is not really correct) but how to help our immune system function to its full potential.

Vitamins and minerals recognized to play a role in immune system function are:

• vitamin A, which we can take in the form of many vegetables available in different seasons (from cabbage to tomatoes, via turnips, chicory, arugula, radicchio, spinach, chard, bell peppers, squash and carrots) and different fruits (such as oranges in winter and apricots in summer). But that's not all: eggs, liver, and various cheeses (taleggio, pecorino romano, caciotta, fontina, and Parmigiano Reggiano) are also sources of vitamin A;
• B vitamins, particularly B6, B9 and B12. Vitamin B6 and vitamin B12 can be taken easily with meats; the former is also abundant in garlic. Vitamin B9, on the other hand, is found in the form of folate in many vegetables (especially green leafy vegetables) and legumes, but eggs are also a good source;
• vitamin C, which is abundant in fruits and vegetables (kiwifruit, oranges, clementines, lemons, currants, strawberries, broccoli, turnip greens, Brussels sprouts, cauliflower, cabbage, radicchio, arugula, and bell peppers);
• vitamin D, which unfortunately is present in very few foods, among which the main sources are fatty fish such as mackerel, salmon, sardines, and tuna;
• iron, present in a form that is particularly absorbable within meats and more difficult to assimilate from plant sources such as legumes;
• selenium from tuna, sardines, mussels and clams, as well as from lamb and beans;
• zinc from nuts, anchovies and sardines, beans and chickpeas, carrots and broccoli, corn and spelt, and various cheeses and meats;
• copper, also found in dried fruits and several fish products.

This long list of immune-boosting foods reiterates how the best choice for promoting a well-functioning immune system at the dinner table is to ensure that you eat as varied a diet as possible. In some cases, however, some extra precautions may be necessary.

When to take supplements?
In particular, it can be difficult to secure through food all the vitamin D that our immune system needs. This is because, as mentioned, its food sources are very few and, therefore, there are few foods that boost immune defenses by supplying the body with this valuable vitamin.

In fact, our body is equipped to produce this substance itself. To do so, however, it needs the sun's rays, which in our latitudes are not sufficiently intense all year round and from which-let's face it-we are increasingly hiding because of the life we find ourselves leading, which is increasingly relegated to enclosed spaces.

The consequence is widespread vitamin D deficiency, from which our immune defenses can also suffer. This is why it may be a good idea to take a dietary vitamin D supplement-a strategy that should, however, be combined with increased (albeit controlled) exposure to direct sunlight.

In other cases it may be useful to take iron supplements, allies both in cases of known deficiencies and when, following a purely plant-based diet, it is more difficult to obtain high amounts from food. Depending on the case, however ,supplements of B vitamins may be useful when our diet is particularly poor in foods of animal origin or green leafy vegetables .

Finally, in some cases the diet may promote an excess of inflammatory phenomena that is completely counterproductive, for example because it is unbalanced toward the intake of Omega 6 fat sources. To rebalance it, Omega 3 supplements come to our aid.

Why fight inflammation? 

We learned this during our fight against the new coronavirus responsible for the COVID-19 pandemic: when the immune system becomes overfired, it can do more harm than good. And also during the fight against the coronavirus, various strategies based on the administration of nutrients that would help keep precisely that inflammation in check were tried. Those tested included Omega 3, fats renowned precisely for their anti-inflammatory properties.

Omega 3s have been associated with regulating the activity of several cells of the immune system, reduce the production of the molecules responsible for that "inflammatory storm" we have heard so much about in connection with the new coronavirus, and are the precursors of molecules that help to turn off ongoing inflammation.

Fatty fish is the best food source we have available to us to fill up on the biologically active forms of Omega 3. So again, to help our immune system we should bring salmon, tuna, mackerel, sardines, sardines, and herring to the table. But if this is not possible (for example, because we are allergic to fish or because we have chosen not to eat fish for ethical or environmental sustainability issues) we can get our fill thanks to dietary supplements based on algal oil, risk-free for allergy sufferers and also suitable for those following a vegan diet.

The same supplements can also be useful in case we wish to support our diet in boosting the proper functioning of our immune system. In addition to those made from algal oil, in the absence of allergies or to shellfish, you can also choose from those made from fish oil, cod liver oil o krill oil.

Bibliographic references:

Arnardottir H et al. Immunomodulation by intravenous omega-3 fatty acid treatment in older subjects hospitalized for COVID-19: A single-blind randomized controlled trial. Clin Transl Med. 2022 Sep;12(9):e895. doi: 10.1002/ctm2.895

European Commission. EU Register of Health Claims.

Create. Food composition tables

Gutiérrez S et al. Effects of Omega-3 Fatty Acids on Immune Cells. Int J Mol Sci. 2019 Oct 11;20(20):5028. doi: 10.3390/ijms20205028.

Hathaway D et al. Omega 3 Fatty Acids and COVID-19: A Comprehensive Review. Infect Chemother. 2020 Dec;52(4):478-495. doi: 10.3947/ic.2020.52.4.478