Is there such a thing as an “Immunity diet”?

The relationship between nutrition and immunity is deep and complex, and still under study. 

But it has been proven that they influence each other: nutrition impacts immunity, and immunity has an effect on our bodies’ response to some foods. Furthermore, we have to account for demographics, environmental and lifestyle factors, to impact our immunity. Highly active athletes, children, and elders are the most susceptible to developing upper respiratory tract infections.

Generally, a diet rich in whole-grains, diverse fruits and vegetables, beans, legumes, fermented dairy (low in sugar or unsweetened), eggs, with some fatty fish, and supplemented with B12 if vegan, should provide enough nutrients to nurture our immunity. Since the pandemic, some studies have highlighted the benefits of a plant-based or pescatarian dietary pattern to minimize the risk of developing COVID-19.

In a nutshell, micronutrients associated with immune support are: Vitamins A, C, D, E, B6, B9, and B12, Iron, Zinc, Copper and Selenium. Amino acids (from protein) are also very important as they provide the building blocks for immune cells and signaling molecules, and sufficient omega-3 intake will help to fight inflammation.

So let’s make sure to get enough amino acids (from wholefoods rich in protein) and sufficient omega-3s, such as from fatty fish, or seeds (chia, flaxseed), avocados, nuts, or even DHA-EPA supplements if you are vegan.

You can’t go wrong with a whole-food balanced diet, either vegetarian or pescatarian, if you take care of your calcium, iron, and B12 (need to be supplemented for vegans), according to recent research.

Fiber:

A diet rich in fruits, mushrooms, vegetables and wholegrains will help our gut bacteria to stay healthy and protect us from pathogens.

The polyphenols in berries, dark green vegetables, dark chocolate (that is good news !), and even coffee beans will provide antioxidants to fight inflammation.

For vitamin D:

Especially during the winter months, when exposure to sunlight is limited and if fatty fish are not consumed quite regularly, it is recommended to supplement with D3. Also, it is important to be aware that, as we age, our body's ability sadly becomes less effective in producing it from the sunlight.

Foods to avoid: basically, try to avoid trans-fat and high-fat foods, highly processed foods, which are all inflammation-promoters. Sugary foods (containing refined sugar), high fructose corn syrup-containing foods (check the ingredients).

However, sugary foods, because their overconsumption is linked to fat gain and metabolic syndrome, are a must when it comes to endurance or high-intensity exercise. So, don’t ban your sports drinks, gels, or gummies from your training or races! But prioritize more complex carbs in your daily dietary intake (not around exercise).

Other recommended lifestyle practices: Drinking plenty of water, getting enough sleep, practicing basic hygiene, managing stress and exercising regularly, to state the obvious!

In conclusion, there is no magic trick, but a nutrient rich-whole foods diet seems the way to go, which should bring all essential micro and macronutrients to nurture our immune system.

Calder, P.C. 2022. Foods to deliver immune-supporting nutrients. Current Opinion in Food Science. 10.1016/j.cofs.2021.12.006

Govers, C., Calder, P.C, Savelkoul, H.F.J., Albers, R., & van Neerven, R.J.J. 2022. Ingestion, Immunity, and Infection: Nutrition and Viral Respiratory Tract Infections. Frontiers in Immunology. 10.3389/fimmu.2022.841532

Murni, I.K, Prawirohartono, E.P, & Triasih, R. 2021. Potential Role of Vitamins and Zinc on Acute Respiratory Infections Including Covid-19. Global Pediatric Health. 10.1177/2333794X211021739

Venter, C., Eyerich, S., Sarin, T., & Klatt, K.C. 2020. Nutrition and the Immune System: A Complicated Tango. Nutrients. 10.3390/nu12030818