Between coronavirus and ‘infodemia’ (the epidemic of redundant and often contradictory information) it seems useful to take stock of what to do. Professor Luc Montagnier, Nobel laureate in medicine, insists on the need to strengthen the immune system. And scientific evidence shows us how, with diet first and foremost.
Coronavirus, the word from Prof. Luc Montagnier
Luc Montagnier – a physician, biologist and virologist who was awarded the Nobel Prize in Medicine in 2008 for the discovery of HIV – gave an extensive interview on coronavirus to Giulietto Chiesa on Pandora TV on 2/25/20. We report some brief excerpts from it, starting with a call not to panic. We are faced with ‘a highly transmissible virus‘ that is spreading in many countries and is not dangerous per se as much as in the possible complications at the lung level. ‘So we should take some additional precautions.’
– Adopt essential hygiene practices. ‘You need to wash your hands very often, do not breathe through your mouth but only breathe through your nose.’ We add, recalling the hygiene practices that have been in place for decades in the Far East, those who cough, even from a simple flu, should avoid going outside and still wear a mask to protect others. Given that the virus can also be transmitted by people who are positive for it even before or in the absence of the onset of symptoms. (Update: For good hygiene and sanitation practices to be adopted, including in workplaces, see the protocol on Covid-19 containment measures agreed between the social partners on 14.3.20),
– strengthen the immune system, to prevent a virus that in itself is not particularly dangerous, when contracted, from causing (pulmonary) complications.
‘We don’t have specific inhibitors of the virus, but we all have good immune systems.’ (…) Our most important defense now is the immune system’.
It is therefore necessary to strengthen, or at least ‘Keeping our immune system in good shape. For this purpose we need to take all kinds of antioxidants that exist. In fact, part of the disease, caused by the virus, is due to oxidative stress. And oxidative stress is due to free radicals (ROS), molecules that oxidize others. Therefore, we should control oxidative stress by taking antioxidants‘.
The antioxidants also available in Italy indicated by Prof. Montagnier are fermented papaya extract, which he has been proposing for many years and ‘is a good product because it keeps antioxidant enzymes high.’ Glutathione is another product ‘less well-known but very active. It can be taken orally, in pill form, and this also works very well. But vitamin C, vitamin D are also very useful. And for the future we are working with some Chinese friends who have identified some even more effective antioxidant enzymes, which I hope will be available soon‘.
Strengthening the immune system with diet
A realistic strategy for dealing with the situation is to provide our bodies with all those molecules that science has shown are capable of strengthening the immune system. Indeed, it is well known that optimal immunocompetence depends on nutritional status, and micronutrient deficiencies-as well as unbalanced diets-can reduce defenses against infection.
There is a bidirectional interaction between nutrition, infection, and immunity:
– immune response is compromised if nutrition is insufficient, predisposing people to infections, while at the same time
– poor nutritional status can be aggravated by the same immune response to infection.
Resistance to infection can therefore be improved by devoting attention to the intake of certain micronutrients- with respect to which deficiencies may be found, especially at certain stages of life (the elderly and children)-and an optimal diet, that is, varied and balanced.
Vitamins and the immune system
Micronutrients play vital roles throughout the immune system. Those most essential for supporting immunocompetence are vitamins A, C, D, E, B6 and B12, folic acid. As well as iron, copper, selenium and zinc.
Vitamin D. Innate immune cells (e.g., monocytes, macrophages, dendritic cells) have the vitamin D receptor that increases their differentiation, stimulates their proliferation and cytokine production. The active form of vitamin D (1,25-dihydroxyvitamin D3) regulates the production of antimicrobial proteins, which can directly kill pathogens, particularly bacteria.
▶️ The foods richest in vitamin D are cod liver oil, fatty fish (e.g., mackerel, sardine, tuna, and salmon), oysters and shrimp, egg yolk; mushrooms (the only plant source of vitamin D, especially maitake and chanterelles), fatty cheeses, and butter.
Vitamin C. Effective antioxidant against ROS(Reactive Oxygen Species) that are formed when pathogens are killed by immune cells. Regenerates other antioxidants, such as glutathione and vitamin E. Promotes collagen synthesis, thereby supporting the integrity of skin barriers. It stimulates the production, function and movement of leukocytes (e.g., neutrophils, lymphocytes, phagocytes). It plays a role in antimicrobial activities and chemotaxis. Professor Montaigner, in his interview, suggests an intake of 1000 mg/day.
▶️ Prime sources of vitamin C are cilantro, bell peppers, black currants, fresh thyme, parsley, cruciferous vegetables (cabbage, savoy cabbage, broccoli), kiwi, and citrus fruits.
Vitamin A. Helps maintain the structural and functional integrity of mucosal cells, innate barriers (e.g., skin, respiratory tract, etc.). It is important for the normal functioning of innate immune cells (macrophages, neutrophils). Necessary for proper functioning of T and B lymphocytes, thus for generation of antibody responses to antigen. Involved in the development and differentiation of Th1 and Th2 cells, it supports the Th2 anti-inflammatory response.
▶️ Found in cod liver oil, liver, hot pepper, dried apricots, carrots, broccoli and green cabbage, sweet potato, pumpkin.
Vitamin E. It is an important fat-soluble antioxidant that protects the integrity of cell membranes from damage caused by ROS. Enhances IL-2 production, T-cell-mediated functions, and lymphocyte proliferation. It optimizes and enhances Th1 and suppresses Th2 response.
▶️ Vegetable oils (peanut, corn, sunflower, extra virgin olive oil), chili peppers, sunflower seeds, almonds, curry, oregano, hazelnuts, avocado, kiwi are rich in it .
Vitamins B6 and B12 help regulate inflammation. They play a role in antibody production, cytokine production, and lymphocyte proliferation and differentiation. They maintain the Th1 immune response.
▶️ Reference foods for B6 are whole grains and flours, lentils, milk, avocados, nuts, peppers, spinach, broccoli. For B12, aged cheeses, soy products, eggs, milk, liver and offal, shellfish, fish (tuna, cod, sardines, and mackerel).
Folic acid. Maintains innate immunity. It is important for antibody response to antigens. Supports Th1-mediated immune response.
▶️ Abound in liver and offal; asparagus, broccoli, artichokes, Brussels sprouts, cauliflower and whole grains; legumes; oranges, strawberries and nuts.
Metals and the immune system
Some metals are also important in modulating immune responses. For T lymphocyte differentiation and proliferation, antibody production, and in cellular immunity, as well as for antioxidant action (selenium and zinc). Which ones and where:
– Selenium in whole grains, mustard and sunflower seeds, eggs;
– iron in liver, beef and horsemeat, eggs, some fish (anchovy, mullet, sardine, tuna), legumes, and nuts,
– zinc in fish and meat, cereals (wheat germ and oats), legumes, nuts, and seeds (pumpkin, sesame, and sunflower),
– copper in liver and offal, mushrooms, cashews, lentils, almonds.
Amino acids and the immune system
Two nonessential amino acids, in turn, play a major role in the immune system:
– glutamine. Important amino acid for immune cells such as lymphocytes, natural killer cells, and macrophage proliferation. Essential for glutathione synthesis.
▶️ Eggs, beef, milk, tofu and white rice are rich in glutamine,
– arginine. It enhances T-cell function, is the precursor of nitric oxide, which plays an important role in coagulation, vasodilation, vascular permeability, and destruction of microbial pathogens.
▶️ Rich in arginine are soybeans, pumpkin seeds, cod, seafood, eggs, and red and white meat.
Tryptophan, an essential amino acid, in turn plays an important role in stimulating the immune system. Due to metabolism by the microbiota of its residual portion (upon intestinal absorption) and the formation of indolic derivatives that effectively activate anti-inflammatory receptors (AhRs).
▶️ Sources of tryptophan include eggs, soybeans, sesame and sunflower, aged cheeses, meat and fish.
Omega-3 fatty acids and prevention
Omega3 fatty acids (EPA and DHA) are important precursors of molecules to promote the resolution of inflammation, enhance bacterial killing by macrophages, and increase tissue regeneration.
▶️ ω-3s are found in flaxseed, walnut, hemp and chia oils, as well as in some fish(salmon including smoked salmon, cod, tuna, sardines).
Microbiome, diet, and the immune system
The microbiome-the microbial community found in the intestinal tract-plays a key role in modulating metabolic responses and the immune system. And diet, once again, plays a crucial role.
Dietary fibers feed the microbiota, which metabolizes them to produce short-chain fatty acids (SCFAs). SCFAs in turn, via receptors in the gut(the ‘second brain‘), send ‘signals’ to the central nervous system with the purpose of modulating, in the physiological range, energy homeostasis, carbohydrate and lipid metabolism, and suppress inflammatory signals.
▶️ Some fibers in particular have an immune-stimulating effect on immune cells. This effect has been demonstrated in the pectin arabin – found in the skin of apples, pears, apricots and plums – and in β-1,3- glycan (found in mushrooms).
The immune system is then stimulated by important anti-inflammatory receptors (AhR, Aryl Hydrocarbon Receptor) through exogenous ligands for AhR that are derived from edible plant tissues, e.g., vegetables, fruits, tea, and herbs.
▶️ Polyphenols may in turn activate immune function by stimulation of AhR receptors. Polyphenols are a family of about 5,000 naturally occurring organic molecules found in plants. The best known for beneficial properties on human health are quercitin, resveratrol, epigallocatechin, anthocyanins, and tirisol.
Mediterranean diet, immune system and health
An authentic Mediterranean diet can offer all the molecules that have important action on our immune system. With plenty and variety of vegetables and fruits (all the better if organic), fiber and complex polysaccharides (whole grains and legumes), proteins of various matrices, and extra virgin olive oil.
▶️ Dietary supplements can help ensure that daily micronutrient requirements are met, sometimes even stimulating other favorable reactions. But no supplement can ever compensate for an underlying nutritional imbalance. The microbiota must be nourished with healthy foods, without flooding the gastrointestinal tract with junk food that instead triggers inflammatory processes.
A scientific study just published on Gut demonstrates, moreover, how ‘nutritional correction’ based on the Mediterranean diet-with increased intakes of fiber, vitamins (C, B6, B9, thiamine) and minerals (Cu, K, Fe, Mn, Mg)-can favorably remodel the gut microbiota even in the elderly within a few months.
Dario Dongo
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Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
