The Delivery of Probiotics and Prebiotics to Infants

Multistrain Probiotics Alleviate Diarrhea by Modulating Microbiome-Derived Metabolites and Serotonin Pathway

Diarrhea, a common gastrointestinal symptom in health problems, is highly associated with gut dysbiosis. The purpose of this study is to demonstrate the effect of multistrain probiotics (Sensi-Biome) on diarrhea from the perspective of the microbiome-neuron axis. Sensi-Biome (Lactiplantibacillus plantarum, Bifidobacterium animalis subsp. lactis, Lactobacillus acidophilus, Streptococcus thermophilus, Bifidobacterium bifidum, and Lactococcus lactis) was administered in a 4% acetic acid-induced diarrhea rat model at concentrations of 1 × 108 (G1), 1 × 109 (G2), and 1 × 1010 CFU/0.5 mL (G3). Diarrhea-related parameters, inflammation-related cytokines, and stool microbiota analysis by 16S rRNA were evaluated. A targeted and untargeted metabolomics approach was used to analyze the cecum samples using liquid chromatography and orbitrap mass spectrometry. The stool moisture content (p < 0.001), intestinal movement rate (p < 0.05), and pH (p < 0.05) were significantly recovered in G3. Serotonin levels were decreased in the multistrain probiotics groups. The inflammatory cytokines, serotonin, and tryptophan hydroxylase expression were improved in the Sensi-Biome groups. At the phylum level, Sensi-Biome showed the highest relative abundance of Firmicutes. Short-chain fatty acids including butyrate, iso-butyrate, propionate, and iso-valeric acid were significantly modified in the Sensi-Biome groups. Equol and oleamide were significantly improved in the multistrain probiotics groups. In conclusion, Sensi-Biome effectively controls diarrhea by modulating metabolites and the serotonin pathway.

A combination of three probiotic strains for treatment of acute diarrhoea in hospitalised children: an open label, randomised controlled trial

Acute diarrhoea continues to be a leading cause of morbidity, hospitalisation, and mortality worldwide, and probiotics have been proposed as a complementary therapy in the treatment of acute diarrhoea. The goal of this study is to assess the efficacy and safety of three combined probiotic strains, Bifidobacterium lactis Bi-07, Lactobacillus rhamnosus HN001, and Lactobacillus acidophilus NCFM, as an adjunct to rehydration therapy in treatment of acute watery diarrhoea in hospitalised children. Eligible diarrheal children were randomised into intervention group (IG, n=96, conventional treatment for diarrhoea in combination with probiotics) and control group (CG, n=98, conventional treatment for diarrhoea without probiotics). The primary assessments of this study were duration of diarrhoea and hospital stay and improvement in diarrhoea symptoms. Significantly more children in the IG showed improvements in diarrhoea (defined as a decrease of stool frequency to no more than four times per day and an improved stool consistency within 24-48 h after the treatment) than those in the CG (96.9 vs 79.6%, P<0.05). Children supplemented with the mixed strains had a 22.5 h shorter (121.4±13.7 h vs 143.9±19.8 h) mean duration of diarrhoea and 1.2 d shorter hospital stays (5.1±1.2 d vs 6.3±1.4 d) than children only receiving the rehydration therapy (P<0.05). The prevalence of constipation of children in the IG (3.1%) was markedly lower (P<0.05) than that of children in the CG (13.3%) after treatment. In conclusion, the mixture of three probiotic strains given to children aged 1-3 years resulted in shorter durations of diarrhoea and hospitalisation and a higher percentage of improved children.

Early-Life Gut Microbiome-The Importance of Maternal and Infant Factors in Its Establishment

The early-life microbiome is gaining appreciation as a major influencer in human development and long-term health. Multiple factors are known to influence the initial colonization, development, and function of the neonatal gut microbiome. In addition, alterations in early-life gut microbial composition is associated with several chronic health conditions such as obesity, asthma, and allergies. In this review, we focus on both maternal and infant factors known to influence early-life gut colonization. Also reviewed is the important role of infant feeding, including evidence-based strategies for maternal and infant supplementation with the goal to protect and/or restore the infant gut microbiome.

Physiological effects of prebiotics and its role in prevention of necrotizing enterocolitis in preterm neonates

Necrotizing enterocolitis (NEC) is one of the most serious gastrointestinal emergencies in very low birth weight (VLBW) preterm neonates, affecting 7-14% of these neonates. Due to the seriousness of the disease, prevention of NEC is the most important goal. Current evidence from systematic review and meta-analysis revealed that probiotics are the most promising intervention in reduction of the incidence of NEC in VLBW neonates. As per the evidence, prebiotics modulate the composition of human intestine microflora to the benefit of the host by suppression of colonization of harmful microorganism and/or the stimulation of bifidobacterial growth, decreased stool viscosity, reduced gastrointestinal transit time, and better feed tolerance. Prebiotics may be potential alternatives or adjunctive therapies to probiotics, despite a lack of evidence supporting its clinical efficacy in prevention of NEC. In this article, we discuss evidence-based physiological effects of prebiotics and its therapeutic role in prevention of NEC.

Efficacy of Synbiotics for Treatment of Bacillary Dysentery in Children: A Double-Blind, Randomized, Placebo-Controlled Study

Bacillary dysentery is a major cause of children's admission to hospitals. To assess the probiotic and prebiotic (synbiotics) effects in children with dysentery in a randomized clinical trial, 200 children with dysentery were studied in 2 groups: the synbiotic group received 1 tablet/day of synbiotic for 3-5 days and the placebo group received placebo tablets (identical tablet form like probiotics). The standard treatment was administered for all patients. Duration of hospitalization, dysentery, fever, and the weight loss were assessed in each group. It was concluded that there was no significant difference in both groups in the baseline characteristics. The mean duration of dysentery reduced (P < 0.05). The mean duration of fever has been significantly reduced in the synbiotic group (1.64 ± 0.87 days) in comparison to the placebo group (2.13 ± 0.94 days) (P < 0.001). Average amount of weight loss was significantly lower in the synbiotic group in comparison to that in the placebo group (129.5 ± 23.388 grams and 278 ± 28.385 grams, resp.; P < 0.001). There was no significant difference in the mean duration of hospitalization in both groups (P > 0.05). The use of synbiotics as an adjuvant therapy to the standard treatment of dysentery significantly reduces the duration of dysentery, fever, and rate of weight losses. The trial is registered with IRCT201109267647N1.

Short-term, daily intake of yogurt containing Bifidobacterium animalis ssp. lactis Bf-6 (LMG 24384) does not affect colonic transit time in women

The present study investigated the effect of Bifidobacterium animalis ssp. lactis Bf-6 (LMG 24 384) (Bf-6)-supplemented yogurt on colonic transit time (CTT). A triple-blinded, randomised, placebo-controlled, two-period cross-over trial was conducted with sixty-eight women with a self-reported history of straining during bowel movements or hard or lumpy stools in the past 2 years. As per regulatory requirements for probiotic studies, eligible women were generally healthy and not actively constipated at the time of enrolment. Participants consumed both Bf-6 and placebo yogurts for 14 d each in a randomised order, with a 6-week washout period between the treatments. The primary outcome, CTT, was assessed via Sitz marker X-rays. The average CTT was 42·1 h for the active period and 43·3 h for the control period (mean difference 1·2 h, 95 % CI - 4·9, 7·4). Since the statistical tests for the cross-over study implied that the mean CTT for the active and control periods in period 2 were biased, the standard protocol suggests examining the results of only period 1 as a traditional randomised controlled trial. This showed that the mean CTT was 35·2 h for the active period v. 52·9 h for the control period (P= 0·015). Bootstrapping demonstrated that both the mean and median differences remained significant (P= 0·016 and P= 0·045, respectively). Few adverse events were noted, with no differences among the active and control periods. The paired analysis showed no differences between the active and control periods during the cross-over trial. Further trials should be conducted in populations with underlying problems associated with disordered transit to determine the potential value of probiotic supplementation more accurately.

Relevance of pre- and postnatal nutrition to development and interplay between the microbiota and metabolic and immune systems

Early-life programming is becoming an established concept that states that the environment during early development affects health and disease in adulthood, probably via epigenetic mechanisms such as DNA methylation, histone modifications, RNA silencing, or a combination. Accumulating evidence suggests that nutrition during pregnancy and early postnatal life is one of the most important environmental cues that programs microbiological, metabolic, and immunologic development. The neonatal period is crucial for the early microbial colonization of the almost sterile gastrointestinal tract of the newborn infant. These first colonizers play an important role in host health because they are involved in nutritional, immunologic, and physiologic functions. Evidence from animal and human studies indicates that the composition of the gut microbiota has an effect on body composition, digestion, and metabolic homeostasis. Furthermore, the functionality of the metabolism develops after birth when the newborn is first exposed to nutrition via the gastrointestinal tract. Exposure to environmental microbial components is also suggested to have a key role in the maturation process of the immune system, and in turn the immune system shapes the composition of the microbiota. Therefore, the use of nutritional strategies to program the microbiota composition to favor a more beneficial bacterial population and to support the development of the metabolic and immune systems may provide a good opportunity to prevent later health problems such as obesity, diabetes, and allergy.

Effectiveness of probiotics in the prophylaxis of necrotizing enterocolitis in preterm neonates: a systematic review and meta-analysis

OBJECTIVE

To elucidate the benefits of using probiotics in the prevention of necrotizing enterocolitis (NEC) and its complications in preterm newborns.

METHOD

This was a systematic review of randomized controlled trials, which included studies retrieved from three databases (MEDLINE, Embase, and LILACS), using a combination of the terms (necrotizing enterocolitis) AND (probiotics).

RESULTS

11 randomized trials were included, totaling 2,887 patients, 1,431 in the probiotic group and 1,456 in the control group. There was a reduction in the incidence of NEC (NNT=25), overall death (NNT=34), and neonatal sepsis (NNT=34) in the probiotic group compared to the control group. Patients that received probiotic supplementation had lower food reintroduction time (p<0.001) and hospitalization time (p<0.001) when compared to those not receiving probiotics. There was no difference in mortality caused by NEC.

CONCLUSION

In premature newborns, the use of probiotics is effective as a prophylaxis for NEC and its complications.

Probiotics, prebiotics infant formula use in preterm or low birth weight infants: a systematic review

BACKGROUND

Previous reviews (2005 to 2009) on preterm infants given probiotics or prebiotics with breast milk or mixed feeds focused on prevention of Necrotizing Enterocolitis, sepsis and diarrhea. This review assessed if probiotics, prebiotics led to improved growth and clinical outcomes in formula fed preterm infants.

METHODS

Cochrane methodology was followed using randomized controlled trials (RCTs) which compared preterm formula containing probiotic(s) or prebiotic(s) to conventional preterm formula in preterm infants. The mean difference (MD) and corresponding 95% confidence intervals (CI) were reported for continuous outcomes, risk ratio (RR) and corresponding 95% CI for dichotomous outcomes. Heterogeneity was assessed by visual inspection of forest plots and a chi² test. An I² test assessed inconsistencies across studies. I²> 50% represented substantial heterogeneity.

RESULTS

Four probiotics studies (N=212), 4 prebiotics studies (N=126) were included. Probiotics: There were no significant differences in weight gain (MD 1.96, 95% CI: -2.64 to 6.56, 2 studies, n=34) or in maximal enteral feed (MD 35.20, 95% CI: -7.61 to 78.02, 2 studies, n=34), number of stools per day increased significantly in probiotic group (MD 1.60, 95% CI: 1.20 to 2.00, 1 study, n=20). Prebiotics: Galacto-oligosaccharide/Fructo-oligosaccharide (GOS/FOS) yielded no significant difference in weight gain (MD 0.04, 95% CI: -2.65 to 2.73, 2 studies, n=50), GOS/FOS yielded no significant differences in length gain (MD 0.01, 95% CI: -0.03 to 0.04, 2 studies, n=50). There were no significant differences in head growth (MD -0.01, 95% CI: -0.02 to 0.00, 2 studies, n=76) or age at full enteral feed (MD -0.79, 95% CI: -2.20 to 0.61, 2 studies, n=86). Stool frequency increased significantly in prebiotic group (MD 0.80, 95% CI: 0.48 to 1.1, 2 studies, n=86). GOS/FOS and FOS yielded higher bifidobacteria counts in prebiotics group (MD 2.10, 95% CI: 0.96 to 3.24, n=27) and (MD 0.48, 95% CI: 0.28 to 0.68, n=56).

CONCLUSIONS

There is not enough evidence to state that supplementation with probiotics or prebiotics results in improved growth and clinical outcomes in exclusively formula fed preterm infants.

Probiotics and prebiotics in pediatrics

This clinical report reviews the currently known health benefits of probiotic and prebiotic products, including those added to commercially available infant formula and other food products for use in children. Probiotics are supplements or foods that contain viable microorganisms that cause alterations of the microflora of the host. Use of probiotics has been shown to be modestly effective in randomized clinical trials (RCTs) in (1) treating acute viral gastroenteritis in healthy children; and (2) preventing antibiotic-associated diarrhea in healthy children. There is some evidence that probiotics prevent necrotizing enterocolitis in very low birth weight infants (birth weight between 1000 and 1500 g), but more studies are needed. The results of RCTs in which probiotics were used to treat childhood Helicobacter pylori gastritis, irritable bowel syndrome, chronic ulcerative colitis, and infantile colic, as well as in preventing childhood atopy, although encouraging, are preliminary and require further confirmation. Probiotics have not been proven to be beneficial in treating or preventing human cancers or in treating children with Crohn disease. There are also safety concerns with the use of probiotics in infants and children who are immunocompromised, chronically debilitated, or seriously ill with indwelling medical devices. Prebiotics are supplements or foods that contain a nondigestible food ingredient that selectively stimulates the favorable growth and/or activity of indigenous probiotic bacteria. Human milk contains substantial quantities of prebiotics. There is a paucity of RCTs examining prebiotics in children, although there may be some long-term benefit of prebiotics for the prevention of atopic eczema and common infections in healthy infants. Confirmatory well-designed clinical research studies are necessary.

Safety of supplementing infant formula with long-chain polyunsaturated fatty acids and Bifidobacterium lactis in term infants: a randomised controlled trial

Probiotics and long-chain PUFA (LC-PUFA) may be beneficial supplements for infants who are not breast-fed. The aim of the present study is to evaluate the safety of an infant formula containing the LC-PUFA DHA and arachidonic acid (AA) and the probiotic Bifidobacterium lactis by comparing the growth rate of infants fed the supplemented and unsupplemented formulas. One hundred and forty-two healthy, term infants were enrolled in a single-centre, randomised, double-blind, controlled, parallel-group trial, and allocated to receive either standard or probiotic and LC-PUFA-containing experimental formulas. The infants were fed with their assigned formulas for 7 months. The primary outcome (weight gain) and the secondary outcomes (length, head circumference and formula tolerance) were measured throughout the study. LC-PUFA status was assessed at 4 months of age and immune response to childhood vaccines was measured at 7 months of age. There was no significant difference in growth between the two groups. The 90 % CI for the difference in mean weight gain was - 0.08, 3.1 g in the intention-to-treat population and 0.1-3.8 g in the per protocol population, which lay within the predefined boundaries of equivalence, - 3.9-3.9. There were no significant differences in mean length and head circumference. DHA and AA concentrations were higher in infants in the experimental formula group compared with the control formula group. No influence of the supplements on the response to vaccines was observed. Growth characteristics of term infants fed the starter formula containing a probiotic and LC-PUFA were similar to standard formula-fed infants.

The effects of probiotics on feeding tolerance, bowel habits, and gastrointestinal motility in preterm newborns

OBJECTIVE

To investigate the effect of dietary supplementation with a probiotic on feeding tolerance and gastrointestinal motility in healthy formula-fed preterm infants.

STUDY DESIGN

Thirty preterm newborns were enrolled; 10 were exclusively breast-fed, and the remaining 20 were randomly assigned in a double-blind manner to receive either Lactobacillus reuteri ATCC 55730 (at dose of 1 x 10(8) colony forming units a day) or placebo for 30 days. Clinical symptoms of gastrointestinal function (regurgitation, vomiting, inconsolable crying, and evacuation) and physiological variables (gastric electrical activity and emptying) were recorded before and after the dietary intervention.

RESULTS

Body weight gains per day were similar for the 3 groups, and no adverse events were recorded. Newborns receiving probiotics showed a significant decrease in regurgitation and mean daily crying time and a larger number of stools compared with those given placebo. Gastric emptying rate was significantly increased, and fasting antral area was significantly reduced in both the newborns receiving L. reuteri and breast-fed newborns compared with placebo.

CONCLUSIONS

Our results suggest a useful role for L. reuteri supplementation in improving feeding tolerance and gut function in formula-fed preterm newborns.

Assessment of the safety, tolerance, and protective effect against diarrhea of infant formulas containing mixtures of probiotics or probiotics and prebiotics in a randomized controlled trial

BACKGROUND

Probiotics and prebiotics are considered to be beneficial to the gastrointestinal health of infants.

OBJECTIVE

The objective was to evaluate infant formulas containing probiotics and synbiotics (combinations of probiotics and prebiotics) for safety and tolerance.

DESIGN

In a prospective, controlled, double-blind, randomized trial, healthy full-term infants were exclusively fed a control formula or study formulas containing Bifidobacterium longum BL999 (BL999) + Lactobacillus rhamnosus LPR (LPR), BL999 + LPR + 4 g/L of 90% galactooligosaccharide/10% short-chain fructooligosaccharide (GOS/SCFOS), or BL999 + Lactobacillus paracasei ST11 (ST11) + 4 g/L GOS/SCFOS from < or = 2 to 16 wk of age (treatment period). Safety and tolerance were assessed based on weight gain during the treatment period (primary outcome) as well as recumbent length, head circumference, digestive tolerance, and adverse events (secondary outcomes), which were evaluated at 2, 4, 8, 12, 16, and 52 wk of age.

RESULTS

Two hundred eighty-four infants were enrolled. During the treatment period, difference in mean weight gain between control and study formula groups in both the intention-to-treat and per-protocol populations were within the predefined equivalence boundaries of +/-3.9 g/d, indicating equivalent weight gain. Secondary outcomes did not show significant differences between groups during the treatment period.

CONCLUSION

Infants fed formulas containing probiotics or synbiotics show a similar rate in weight gain compared with those fed a control formula and tolerate these formulas well.

[Establishment of the intestinal microflora in neonates]

The intestinal microbiota is a complex ecosystem harbouring about 10(14) micro-organisms composed of nearly 400 hundred species. It plays various important functions in the gut, including metabolic, flora, barrier and stimulation of the intestinal immune system. Most studies have been based on culture, but more recent molecular biology techniques have provided complementary information. The formation of this ecosystem begins rapidly in the newborn; it is sterile at birth and is based on contact with the maternal flora and the surrounding environment. Although little is known about the factors leading to the development of bacteria, numerous external factors will affect the microbial succession: mode of delivery, environmental conditions, type of feeding, gestational age, and antibiotics. Recent data report a delay in intestinal colonization especially of enteric maternal bacteria. Which may be due to strict hygiene measures during birth. The clinical impact of these variations is not known but they could lead to lack of barrier flora or poor immune system stimulation in the gut. Modulation of gut microbiota in neonates with infant formulas containing either probiotics, prebiotics or non viable bacterias and their metabolites, or nucleotides is discussed.

Lactobacillus caseiShirota administered during lactation increases the duration of autoimmunity in rats and enhances lung inflammation in mice

Probiotics are considered to have beneficial effects on the immune system. An association between the composition of microflora and allergies has been demonstrated and modulation of microflora of infants by probiotics might reduce the risk of allergies. To investigate immune effects of probiotics administered early after birth two animal models were used: a mouse model for respiratory allergy; a rat model for experimental autoimmune encephalomyelitis (EAE). Administration of the probioticLactobacillus caseiShirota (LcS) started during lactation and allergy or autoimmunity were induced at an adult age. Results were compared with similar studies in rats and mice that were exposed from an adult age. Early administration of LcS significantly increased lymphocytes in the lungs of female mice and eosinophils in the lungs of male mice. LcS had no effects on ovalbumin-specific serum IgE levels and on ovalbumin-specific cytokine production by spleen cells. In adult mice, LcS enhanced ovalbumin-specific cytokine production by the spleen, whereas other parameters were not affected. Early administration of LcS to rats significantly increased the duration of clinical symptoms of EAE. This was also demonstrated previously in adult rats exposed to LcS. Timing of administration of LcS induced divergent effects on respiratory allergy and only early administration of LcS exacerbated lung inflammation. In the EAE model, LcS stimulated autoimmunity independent of the timing of administration. Our data show that immune effects of probiotics do not necessarily induce beneficial effects. It is therefore important that, in the evaluation of probiotics, efficacy and safety should be demonstrated.

Use of probiotics in pediatrics: rationale, mechanisms of action, and practical aspects

The use of probiotics (ingested microbes that can modify intestinal microbial populations in a way that benefit the host) has moved from concept to actual demonstration of specific benefits by specific microorganisms for specific populations. It is increasingly clear that these benefits to the host are mostly mediated by the profound effect that intestinal microflora (microbiota) have on gut barrier function and host immune response. Intestinal bacteria are more numerous than the human cells of the host that harbors them. Despite having many potential pathogens in this microflora, humans do not routinely get infected. It is no coincidence that gut-associated immune tissue constitutes approximately 80% of all immunologically active cells in the human host. The gut interacts with intestinal bacteria, both resident and ingested, to develop protective mechanisms (via improving gut barrier function and immune stimulation for defense) and appropriate, nonexaggerated responses (via immune modulation and immune tolerance) to support host health. The mechanisms of this interaction between host and bacteria are increasingly being unraveled and in great part explain the clinical benefits that have been reported with specific probiotic bacteria by enhancing host defense mechanisms (such as for treatment and prevention of viral diarrhea and reducing risk of necrotizing enterocolitis), mitigating antibiotic-associated diarrhea, and modulating host immune response (such as in allergic disease).

Clinical evaluation of a new starter formula for infants containing live Bifidobacterium longum BL999 and prebiotics

OBJECTIVES

The larger number of bifidobacteria in the intestine of breast-fed infants has been associated with their better health compared with formula-fed infants. We assessed the safety and tolerability of an experimental formula containing 2 x 10(7) colony-forming units of Bifidobacterium longum BL999 and 4 g/L of a prebiotic mixture containing 90% galacto-oligosaccharides and 10% fructo-oligosaccharides.

METHODS

A 7-mo prospective, randomized, reference-controlled, double-blinded trial was performed in infants who were not breast fed after the 14th day of birth. One hundred thirty-eight infants were enrolled and assigned to receive the control or experimental formula until they were 112 d old. Mean weight gain (primary outcome) and recumbent length, head circumference, tolerability (gastrointestinal symptoms), and overall morbidity (secondary outcomes) were measured at 14, 28, 56, 84, and 112 d of age.

RESULTS

Equivalence in mean weight gain between the two groups was shown. The treatment difference in the intention-to-treat and per-protocol populations were within the predefined equivalence boundaries of +/-3.9 g/d. No statistically significant difference in recumbent length, head circumference, or incidence of adverse events was found between the two groups. Infants in the experimental group had fewer incidences of constipation and had stool characteristics that suggest that the experimental formula was tolerated well. Furthermore, these infants showed a trend toward fewer respiratory tract infections.

CONCLUSIONS

The starter formula containing BL999 and galacto-oligosaccharides/fructo-oligosaccharides is safe and well-tolerated.

Gut responses to enteral nutrition in preterm infants and animals

Preterm birth is associated with immature digestive function that may require the use of total parenteral nutrition and special oral feeding regimens. Little is known about the responses to oral food in the preterm neonate and how enteral nutrients affect the immature gastrointestinal tract (GIT). In vivo studies are difficult to perform in laboratory rodents because of their small body size and that of immature organs at birth, and this makes the large farm animals (e.g., pigs, cattle, sheep) more attractive models in this field. In these species, preterm delivery at 88%-95% gestation is associated clinical complications and degrees of GIT immaturity similar to those in infants born at 70%-90% gestation. Studies in both animals and infants indicate that the immature GIT responds to the first enteral food with rapid increases in gut mass and surface area, blood flow, motility, digestive capacity, and nutrient absorption. To a large extent, the enteral food responses are birth independent, and can be elicited also in utero, at least during late gestation. Nevertheless, preterm neonates show compromised GIT structure, function, and immunology, particularly when delivered by caesarean section and fed diets other than mother's milk. Formula-fed preterm infants are thus at increased risk of developing diseases such as necrotizing enterocolitis, unless special care is taken to avoid excessive nutrient fermentation and bacterial overgrowth. The extent to which results obtained in preterm animals (most notably the pig) can be used to reflect similar conditions in preterm infants is discussed.

Beneficial lactobacilli in food and feed: long-term use, biodiversity and proposals for specific and realistic safety assessments

Lactobacilli have played a crucial role in the production of fermented products for millennia. Their probiotic effects have recently been studied and used in new products. Isolated cases of lactobacillemia have been reported in at-risk populations, but lactobacilli present an essentially negligible biological risk. We analyzed the current European guidelines for safety assessment in food/feed and conclude that they are not relevant for the Lactobacillus genus. We propose new specific guidelines, beginning by granting a 'long-standing presumption of safety' status to Lactobacillus genus based on its long history of safe use. Then, based on the available body of knowledge and intended use, only such tests as are useful will be necessary before attributing 'qualified presumption of safety' status.