Eating crickets for breakfast may be good for gut
Consumption of whole-cricket powder appears to promote the growth of the probiotic gut bacterium Bifidobacterium animalis and reduce plasma concentrations of tumour necrosis factor-α (TNF-α), according to a recent trial.
“To our knowledge, this is the first study of its kind to evaluate the impact of edible cricket consumption on the human gut microbiota. We provide evidence that cricket supplementation selectively changes the gut microbial and metabolite environment,” said researchers, adding that the dietary changes were safe over the duration of the trial.
The study included 20 healthy adults (mean age 26.45±6.33 years; 55 percent female) who had a mean baseline body mass index (BMI) of 23.39±2.46 kg/m2. [Sci Rep 2018;8:10762]
Fourteen weeks of exposure to breakfasts with 25-g of cricket powder led to significant changes in several taxa compared to exposure to the control diet. For instance, the following taxa showed were significantly enriched: unclassified Coprobacillus, unclassified Actinomyces, unclassified Streptococcaceae, Eggerthella lenta and B. animalis. Specifically, B. animalis levels increased by a log fold change of 5.7 following the cricket diet relative to the control breakfasts.
In comparison, abundances of 10 bacterial taxa significantly dropped after the cricket diet: unclassified Acidaminococcus, unclassified Enhydrobacter, unclassified Leuconostocaceae, unclassified Lactobacillus, unclassified Alloscardovia, unclassified Dermacoccus, unclassified Anaeroplasmataceae, unclassified ML615J-28, Oxalobacter formigenes and Lactobacillus reuteri. In particular, there was an almost fourfold decrease in the levels of L. reuteri, specifically, relative to the control diet.
The cricket-enriched breakfasts may also influence inflammatory responses. A human T-cell panel including 13 cytokines and chemokines showed that TNF-α levels were significantly reduced in participants who received the cricket vs control diet (p<0.05).
In terms of safety, responses to the gastrointestinal questionnaire indicated that there were no significant changes in function throughout the study duration, not were there any significant adverse side-effects resulting from cricket consumption.
“Gastrointestinal symptom self-assessments and data from comprehensive metabolic panels suggest that cricket consumption was both safe and tolerable in our study population,” said researchers, noting that there were likewise no significant disruptions in the healthy adult microbiota.
B. animalis is a Gram-positive, nonspore forming, lactic acid-producing bacteria. It is a commercial strain and is one of the best-studies probiotic bacteria. It has been shown in various studies to reduce the likelihood of diarrhoea, decrease antibiotic side effects and improve gastrointestinal function. [Microorganisms 2014;2:92-110]
“To our knowledge, this is the first time a whole food containing chitin has demonstrated bifidogenic potential in healthy humans,” said researchers, adding that “[p]athogen inhibition is one of the primary mechanisms by which probiotics influence human health, along with enhancing gut barrier function.”
The present trial employed a randomized, double-blind, crossover design. Half of the participants were randomly assigned to receive 14 days of breakfasts with 25-g cricket powder, while the other half received a control breakfast. After a 14-day washout period, assignments were switched.
“These findings support the need for future research to evaluate the health impacts of edible insects, beyond their nutritional value, on human microbiota. This may be particularly relevant in populations at risk for malnutrition or environmental enteropathy,” said researchers.