I think this is a very timely post, considering that we are in the midst of holiday season when we all over-indulge and then, come New Year’s, swear we’ll lose all the pounds we’ve pack on! Research out of Ireland, University College Cork, first tested their hypothesis in animals.[i] Prior research had shown that the probiotic bacterium, Bifidobacterium longum APC1472, seems to help modulate the levels of ghrelin, which is a hormone that regulates appetite and fat metabolism.
Using mice with diet-induced obesity, they confirmed that the strain does lead to weight loss, reduces fat deposits, improves glucose tolerance and reduces fasting cortisol levels. They found too that the probiotic reduced levels of the hormone, leptin, which is made by adipose (fat) cells and which helps to regulate energy by balance by inhibiting hunger, thus reducing food consumption and fat storage. They then tested this in humans. Over 100 obese (but otherwise healthy) humans were included in their translational study. The people were divided into controls and treatment groups, and the latter received daily doses of the probiotic for 12 weeks. The results were somewhat promising. In people, the probiotic reduced fasting blood glucose levels, decreased cortisol levels, and improved ghrelin levels. However, the people did not lose weight or fat: “…we show the promising potential of B. longum APC1472 to be developed as a valuable supplement in reducing specific markers of obesity…Most notably, the decrease in fasting plasma glucose induced by B. longum APC1472 may have clinically significant health implications for prediabetic and type 2 diabetes mellitus populations in particular.”
Why did the probiotic not have the same fat/weight reducing effect in people as in mice? The researchers don’t as yet know but they suggest that as opposed to the mice, the humans in the treatment group were not prediabetic, meaning that the weight loss component was due to the normalization of glucose metabolism. If glucose metabolism is already generally normal well – the probiotic may not help much for weight loss. Also, the mouse study was longer than the human study which the researchers suggest may also be a factor. I also note that the humans were given only 10 billion units
The good news is that the research is certainly supporting a role for the probiotic in helping to control prediabetes and diabetes. They also note that the reduction in cortisol levels is really important as there is a well-confirmed relationship between stress and weight gain. (Tell me about it!) Cortisol is your main stress hormone, and when under stressful conditions, the body has a survival mechanism of packing on weight. (Makes sense if you think about it: from an evolutionary standpoint, having the ability to retain weight while under negative circumstances like famine would greatly enhance the chances of survival.) The ability of this species of probiotic to modulate that cortisol stress response is promising in terms of improving mental health as well as physical health: “The translational findings are solid and the modulation of cortisol awakening response, warrant further investigation of this B. longum APC1472 and its potential use as a psychobiotic to improve mental health,” says one of the scientists involved in this work.[ii]
I took a look around to see if this particular strain is yet available for purchase. Here’s what I found, dated December 18th: “The APC Microbiome Ireland SFI Research Centre, which identified and patented Bifidobacterium longum APC1472, is now talking to “interested parties” about the commercialization of the strain.”[iii] So sounds like it will be available someday, but is not as yet.
[i] Schellekens, H, et. al. Bifidobacterium longum counters the effects of obesity: Partial successful translation from rodent to human. EBiom Medicine. 2020. DOI:https://doi.org/10.1016/j.ebiom.2020.103176