A varied diet, which allows for more different foods between the 6th month of age and the completion of the first year of life, helps to control allergies.
The more varied the diet is, the less the child is likely to become allergic to either food or respiratory allergens.
A multicentre study conducted by a team of researchers from Switzerland, France, Finland, Austria and Germany, published in April 2014 on JACI (Journal of Allergy and Clinical Immunology), was able to show how food allergies, eczema, atopic dermatitis, rhinitis and asthma occur more frequently in kids who, between 6 and 12 months of age, have “tried” less types of food than children who instead ate more varied, thus giving a strong preventive role to the plurality and the diversity in meeting with environmental antigens.
In the study, children were assessed up to 6 years of age and the improvement in the allergic conditions was significantly detected from the first year of life up to the 6th.
In the same issue of the journal, a Finnish study could instead highlight how the lower occurrence of eczema and respiratory allergies (including asthma) begins to be evident as early as 9 months of age in children who have met more types of food and have set a more incisive pro-tolerance action into motion.
In their study, Roduit et al. included the introduction (after the first 6 months of age) to fruit and vegetables, cereals, meat, bread, cakes and yogurt, or a broader use of the foods listed above, in addition to cow’s milk, other dairy products, eggs, nuts and oilseeds, fish, soy, margarine, butter and chocolate.
Why this happens
The levels of decrease of asthma were impressive. For each new food introduced within the first year of life, a 26% reduction in asthma manifestation occurred when compared to those children who had a less varied diet.
Regarding eczema, the measured reduction was “only” 14.4% for each new aliment introduced. Therefore, these are all important numbers, which should help think about and send serious messages also in regard to adult tolerance.
The authors’ discussion indicates that such an effect may depend on the activation of the T regulatory cells, that is, those cells stimulating the development of food tolerance (the researchers measured the markers of activation specific for these cells), coming to suggest that the development of food tolerance may then be able to lead the body to develop tolerance both to food and respiratory antigens at the same time.
As if food tolerance (of primary importance in the activation of innate immunity) was also able to control the mechanisms leading to eczema and asthma.
On DocSalus, we often reported on such an important possibility, confirmed by the fact that there are numerous types of asthma which depend on food-related inflammation.
In fact, for years we have been supporting patients with respiratory allergic conditions by following specific therapeutic approaches, as well as by working on the food-related components of most forms of eczema and dermatitis together with Dr. R Cavagna.
How to translate this information on the adult
At least other two considerations can be drawn from the papers published on JACI in April, which are useful for transferring the possible benefits of such knowledge even in adults.
Allergic episodes are reduced, or completely disappear, because tolerance is activated when triggered by cells that deal specifically with this and not because of a different ratio between pro-inflammatory cells with an opposite action (TH1 vs. TH2), which contribute to allergy, instead. Therefore, immunological tolerance may and should be the goal to achieve.
Moreover, it is clear how that result could be achieved thanks to the reduction of inflammation and the control of its immunological effects (in scientific jargon, we are talking of the reduction in the immunoglobulin switch).
Thus, this all means that keeping cytokines such as BAFF under control, which specifically plays a role in these mechanisms and can be measured by a food-related inflammation test, may effectively help monitoring the allergy development.
Tolerance induction may be linked to the variety of bacteria present in the infantile gut, hence the possible protective effect played by exclusive breast-feeding until at least 6 months of age, as it may favour tolerance development thanks to probiotics, whose proliferation is improved by this specific type of feeding.
In 2012 we already described how encountering various food antigens, through the so-called “self-weaning” process, even if in conjunction with breastfeeding, represents an evolutionary stimulus towards immune tolerance, perfectly in accordance with the results of the two articles described above.
The knowledge of these new concepts allows us to activate a series of procedures that, even in the adult, by retracing the path of the new-borns, are able to help controlling and regulating the allergic conditions, which today are steadily growing:
- Following the motto “raw, fresh and colourful”, that is, the habit of eating fruit or vegetables before every meal, known for long as a good way to induce tolerance.
- Maintaining a varied diet, also if suffering from episodes of food hypersensitivity, because choosing to undergo elimination-focused diets means consciously going in opposition to the most recent discoveries of modern immunology.
- Check-up and control of the most important pro-inflammatory cytokines (BAFF, PAF, IL6, TNF-alpha), to avoid triggering allergic phenomena.
- Using supplements able to interact within this network allows not only to control the allergy symptoms, but also to promote the achievement of stable tolerance (Perilla oil, Ribilla, Inositol, Quercetin).
The chances of nutrition to become the most important tool in the prevention and treatment of allergic diseases are increasing every day.