Take home message:
- Health of the new generation start before birth and is affected by the choices and possibilities made by the pregnant mother.
- Asthma and allergies are life-style problems rather than genetic problems.
- We need contact with bacteria, especially in the early stage of life to prevent asthma and allergies.
Nature of nurture in asthma and allergies
Asthma and allergies are mainly environmental problems (nurture) and less a genetic problem (nature). This can be deduced from the very rapid increase in atopic and immunity problems in the past 30-40 years, so even within 1 generation of people. When the separation of former Eastern and Western Germany was over in 1989, it was assumed that former East German children would suffer more from Asthma and allergies. Smelly Trabant cars, coke and coal firing were thought as factors that should have a negative impact on the children. However, comparing the two groups of children gave the opposite result: West German children were more troubled by the effects of prosperity, probably because of the diet and advanced Western lifestyle. 25 years later, the differences have been leveled, since the lifestyle in the former East German Confederation have been aligned. Even when Africans adopt to our way of life, their children face the same allergy problems as Western children. First in the cities, where prosperity is the greatest. It is estimated that over 400 million people in the world suffer from asthma in the next 10 years. Less than a century ago, allergic diseases were extremely rare. Today it is one of the biggest disorders among young people.
How quickly Polish people change their life, was shown after Poland joined the EU. Before that, 50% people had their own cow if you didn’t live in the city. Often single cows that were grazed everywhere on a long chain. Farmer as a side job quickly disappeared. The figures for Asthma and allergy show, however, that only within a 9 years period the proportion of people with atopy in the villages were at the same level as in the larger cities (around 20%). In 2003, still 35% of the village people drank raw milk from their own cow, in 2012 this had dropped to just 9% of the villagers. Whereas atopy among the milk-drinking villagers had a share of 7.5% in 2003, this was 20% in 2012 (Sozanska et al., 2015), just like in the urban environment.
Scientific hypotheses
Two hypotheses have now been drawn up that offer an explanation for the better immune status of farm children, for example. First, the hygiene hypothesis developed by David Strachan (1989) and was based on the alluringly sounding statement: “a little dirt does not hurt,” in other words, we need a certain degree of dirt, contamination, bacteria to develop in a healthy way. In recent years, this hypothesis has been reinforced and supplemented by the microbiome hypothesis, which focuses on how determining different events in early life affect the ultimate development of the intestinal flora, resulting into a healthy immune response (West et al., 2014). Researchers now label the phase of pregnancy and therefore the living and eating habits of the pregnant mother as an important factor. Is the mother healthy, non-obese; what are her eating habits? To which bacteria does she come into contact with? Then the way of delivery (where, how), breastfeeding (length, frequency, mother’s diet) determine the 2nd phase that leaves its mark, how the newborn can develop immunologically. The International Society for Developmental Origins of Health and Disease (DOHaD) therefore refers to the phase in life that starts 9 months before birth and extends to at least 9 months. Some people even talk from the first 1000 days of our life, which starts after fertilization of the egg in the womb. It is becoming increasingly clear that the predisposition for asthma and allergy can be linked to the way in which the intestinal flora can develop in the first year of life (Liu, 2015). One of the first studies that was carried out to what extent the pregnancy influences the later health of a child and even grandchild was done with babies born after the last winter during the Second World War in Amsterdam. There was a great famine in the last winter of the war (1944-1945). In this study, pregnant women held newborns in different fetal stages at the severest point of the famine (0-3, 3-6, 6-9 months of pregnancy). The timing of the mother’s deep malnutrition appeared to have a major impact on the life of the still-unborn child, but curiously also on the children of these children. This is therefore referred to as an epigenetic effect. Epi-genetic means that there are environmental factors that regulate the genetic system, genes can be switched on and off.
This type of cohort studies is important to find correlations between health outcome and underlying factors. Correlations are not telling you the causal factors. It is easier to establish that Western people are increasingly immune disrupted than to understand precisely and mechanically why this is so. The functionality of the immune system is complex, and its regulation has to do with the factors in our lifestyle, the timing, etc. The focus to support the newborn is on the very early development of the new life (Casaca, 2014; Hesla, 2015):
• Building up of the baby’s health starts before birth, in the womb and therefore depends on the diet and lifestyle of the pregnant woman;
• The fetal immune system can be stimulated by endotoxins, remains of bacteria (cell walls) or the entire bacteria itself. Therefore, attention is paid to the biodiversity of the microbial life in and around the pregnant mother (Logan et al., 2016);
• A normal home birth, vaginal in the mother’s own environment, means that the baby can come into contact with the bacteria that belong to the healthy mother. The antibodies delivered by the mother fit for the child. A vaginal birth is the best start for the bacterial inoculation of the newborn;
• The presence of dirt and bacteria in the environment of the newborn.
• The magic of breast milk, the Human Milk Oligosaccharides, that are not digested, but “only” used to grow the gut flora of the infant. Breast milk is the first pre- and probiotic food for the baby.
