Every year, cold and flu season spreads across the world.
It is no different in Portugal. Seasonal flu continues to represent a significant public health issue, due to its high transmissibility, the constant evolution
of viral strains, and the impact on vulnerable populations, due to a lack of immunological preparation and nutritional deficits.
Vitamin C
This excellent nutrient takes the top spot when it comes to its ability to help prevent illness, making it the most common ingredient in cold and flu supplements.
This is because the immune system depends on vitamin C for the healthy production and proper functioning of antibodies and white blood cells — the body's defense system — in addition to helping fight oxidative stress, which weakens immunity.
However, we recommend liposomal vitamin C, especially during cold and flu season. Unfortunately, only 14–30% of the vitamin C in traditional supplements is absorbed by the body, whereas liposomal vitamin C uses a lipid capsule that envelops the nutrient, allowing for much more effective transport to the cells.
Zinc
Zinc is an essential mineral that supports the immune system by promoting the production and proper functioning of immune cells and antibodies. Studies show that zinc can reduce the duration of colds by about two days and that, when taken together with vitamin C, it can further boost its immune-strengthening effects.
Zinc Picolinate 15 120cap – Biogena
Elderberry
Elderberry is another widely used plant-based compound, both as a standalone supplement and as an ingredient in many natural supplements for strengthening the immune system. Thanks to its high content of antioxidants, including polyphenols, elderberry has demonstrated highly interesting antiviral, antibacterial, and immunostimulant properties.
According to a 2022 study published in the journal Plants, elderberries can help fight various types of coronaviruses and even reduce symptoms like fever and congestion by up to 50%.
Elderberry 60vcap - NutraMedix
Vitamin D
Vitamin D is an essential nutrient that immune system cells rely on to function correctly. It also plays an important role in modulating inflammation by reducing the production of pro-inflammatory cytokines, such as IL-6, and increasing the production of anti-inflammatory cytokines, such as IL-10.
For this reason, vitamin D deficiency is frequently associated with autoimmune diseases, weakened immunity, and an increased risk of upper respiratory tract infections. In fact, studies indicate that vitamin D supplementation can reduce the risk of respiratory infections, even in people who are not deficient in this nutrient.
Although vitamin D can be obtained through sun exposure and foods like eggs and wild-caught fish, most people do not get enough from any of these sources, making vitamin D deficiency extremely common.
Vitamin D3 K2 drops 10ml – Biogena
L-Lysine
This essential amino acid is often described as a strong ally in fighting viruses. In a clinical context, it is common to use L-lysine in doses of about 1,000 mg, two to three times per day, adjusted to individual needs.
A study published in the medical journal Dermatologica concluded that supplementation with L-lysine can help reduce the frequency, severity, and healing time of herpes lesions caused by HSV-1.
In addition to supplementation, it is also important to prioritize foods rich in L-lysine, such as wild-caught fish and organic poultry, to naturally support the body.
Medicinal mushrooms
Medicinal mushrooms are everywhere these days — from tinctures and capsules to even coffees. Although they are clearly in the spotlight, mushrooms are nothing new: many have been used in traditional medicine for thousands of years.
One of the most significant effects of many medicinal mushrooms is their antiviral and immune-boosting properties, as is the case with reishi.
Reishi has demonstrated the ability to fight several viruses, including herpes, Epstein-Barr and hepatitis. Studies also indicate that it may be effective against the influenza A virus, responsible for many flu outbreaks throughout the season, including the H1N1 strain, known for its high virulence.
One of the most significant effects of many medicinal mushrooms is their antiviral and immune-boosting properties. In fact, several mushrooms have demonstrated efficacy in the prevention and support for the treatment of respiratory viruses, such as the common cold and even the flu virus
Astragalus (Astragalus membranaceus)
**Astragalus** is an **adaptogenic** herb used in **traditional Chinese medicine for centuries** for its ability to **strengthen the immune system** and **reduce the severity of flu and cold symptoms**.
According to several clinical studies, astragalus **boosts the body's immune response** by increasing the production of immune cells, such as **T lymphocytes** and **macrophages**. Furthermore, astragalus contains compounds such as **saponins** and **polysaccharides**, which exhibit **immunomodulatory** effects so significant that they are currently being studied as potential **adjuvants in antitumor therapies**.
ImmuneMedix™ 120ml - Nutramedix
Samento® (Uncaria tomentosa)
**Samento®**, from **Nutramedix**, is a highly purified extract of *Uncaria tomentosa*, a medicinal plant known as **cat's claw**, traditionally used in South American natural medicine for its potent **immune system support** effect.
What distinguishes Samento® from other forms of cat's claw is that it is **free of tetracyclic oxindole alkaloids (TOAs)**, compounds that can interfere with the desired immunological action. By eliminating these alkaloids, Samento® preserves only the **pentacyclic oxindole alkaloids (POAs)**, which are associated with more **effective and targeted immunomodulatory activity**.
Samento® has been studied for its **antiviral, antibacterial, and anti-inflammatory properties**, and is frequently used in immune support protocols, especially in contexts of persistent infections, chronic inflammation, and periods of greater immune vulnerability, such as the flu and cold season.
Preparing for flu and cold season is less about a single pill and more about building resilience before infections reach their peak intensity.
Think of supplements as an ally and a layer of protection that works best when combined with good sleep habits, an anti-inflammatory diet, and stress management.
