• “. At 3-months the abundance of the genus,  Lachnospira  (L), was decreased (p = 0.008), while the abundance of the species,  Clostridium neonatale  (C), was increased (p = 0.07) in asthmatics. Quartile analysis revealed a negative association between the ratio of these two bacteria (L/C) and asthma risk at 3-months (quartile 1: Odds ratio (OR) = 15, p = 0.02, CI = 1.8 – 124.7; quartile 2: OR = 1.0, ns; quartile 3: OR = 0.37, ns). We conclude that opposing shifts in the relative abundances of  Lachnospira  and  C. neonatale  in the first 3 months of life are associated with preschool age asthma, and that the L/C ratio may serve as a potential early life biomarker to predict asthmadevelopment.” [2016]
• ” One study demonstrated a strong association between high abundance of Faecalibacterium prausnitzii and decreased levels of butyrate and propionate, and established eczema. Lower relative abundance of Ruminococcaceae appears to be implicated in food sensitization and to precede the development of atopic eczema. Decreased relative abundance of Lachnospira, Veillonella, Faecalibacterium, and Rothia in early infancy was reported to be associated with increased asthma risk. Inoculation of germ-free mice with these genera decreased airway inflammation in their offspring thereby proposing a causal role of bacteria in preventing allergic airways disease.” [2016]
• “Low total diversity of the gut microbiota during the first month of life was associated with asthma but not allergic rhino conjunctivitis ( in children at 7 years of age. Measures affecting microbial colonization of the infant during the first month of life may impact asthmadevelopment in childhood.” [2014]
• “Low intestinal microbial diversity during the first month of life was associated with subsequent atopic eczema.” [2012]
• “These results support the general hypothesis that an imbalance in the intestinal microbiome is influencing the development of lifestyle-related disorders, such as allergic disease.” [2011]
• “Presence of older siblings is associated with increased gut microbial diversity and richness during early childhood, which could contribute to the substantiation of the hygiene hypothesis.” [2015]

Actionable Items

Studies have found that generic probiotics and antibiotics do not have any statistically significant effect in human studies. This is not surprising because the same hold true for other conditions associated with a microbiome shift – generic products have no effect. Very specific probiotics and antibiotics do have impact with those conditions. Which ones are effective for Asthma and Eczema is still unknown and to be studied.

There is one exception — Vitamin D, which is known to alter the microbiome

• :”Other known or potential risk factors for severe asthma exacerbations include …vitamin D insufficiency, … In spite of progress in our understanding of the pathophysiology of asthma, we lack reliable instruments or biomarkers to predict severe asthma exacerbations.[2016]
• We find a relationship exists between airway obstruction and 25OHD [Vitamin D] levels in asthmatic adults, and the effect is not explained by the presence of potential confounders such as obesity, allergy and systemic inflammation. [2016]
• “Our results suggest that vitamin D insufficiency is relatively frequent in an equatorial population of children with asthma. In these children, lower vitamin D levels are associated with increased markers of allergy and asthma severity.” [2009]
• ” studies that focused on vitamin D and severity of asthma which suggest a positive association of vitamin D levels with better asthma control, reduced use of asthma medication, fewer asthma exacerbations and lower utilisation of health care facilities for urgent treatment.” [2015]
• “These results suggest that vitamin D supplementation may be effective for the prevention of asthma exacerbations, but the findings need to be confirmed by clinical trials.” [2015]

Vitamin D and the Gut