Page 50 - MI-2-2

Microbes & Immunity Probiotics & obesity

sole indicator of metabolic diseases. Other important A reduction in BMI and weight was observed in a
1
factors to consider include waist circumference and visceral study using a combination of 9 strains, namely B. bifidum
fat area (VFA). Increased waist circumference, resulting W23, B. lactis W51, B. lactis W52, L. acidophilus W37,
1,19
from excess adipose tissue, is positively associated with Levilactobacillus brevis W63, Lacticaseibacillus casei
weight-related cancers, including colon, post-menopausal W56, Ligilactobacillus salivarius W24, L. lactis W19, and
breast, endometrial, and pancreatic cancers. VFA, which L. lactis W58. A significant reduction in weight, BMI,
26
20
measures adipose tissue around internal organs, is a critical waist circumference, fasting glucose, fasting insulin
indicator, as its accumulation is linked to obesity-related HOMA-IR in a study using B. longum BB536, L. rhamnosus
metabolic disorders. In contrast, subcutaneous adipose HN001 for 26 measured breast cancer survivors. However,
tissue does not show a significant positive relationship the small sample size of this study may affect the quality of
with these disorders and is not considered a major risk analysis concluded. 27
19
factor. Excess adipose tissue accumulation found on the Michael et al. found that the probiotic combination
22
liver leads to hepatic steatosis and is measured in studies Lab4P, consisting of L. acidophilus CUL60, L. acidophilus
involving mice. 6,13,14,17,18 CUL21, L. plantarum CUL66, B. bifidum CUL20, and
The relationship between SUA and VFA is intriguing B. animalis subsp. lactis CUL34, significantly reduced body
but not yet fully understood. An increase in VFA is often weight, waist and hip circumference, and blood pressure
accompanied by a rise in SUA, potentially as a mediating in overweight Bulgarian adults. This suggests Lab4P’s
response. Since elevated VFA is linked to hypertension, potential as an effective probiotic for managing obesity
cardiovascular disease, and diabetes, SUA has emerged and related metabolic risks. The microbial diversity
22
as a biomarker for these risks due to its apparent positive increase as the Firmicutes/Bacteroidetes ratio decrease
correlation. Lactobacillus probiotics, which synthesize in both low-dose and high-dose probiotic groups in the
28
enzymes that degrade SUA, may help mitigate its effects study by Tremblay et al. using the following combination:
and reduce VFA. Similarly, Bifidobacterium probiotics have L. helveticus R0052, L. rhamnosus R0011, L. casei R0215,
been shown to decrease both VFA and SUA, leading to Pediococcus acidilactici R1001, B. breve R0070, B. longum
favorable outcomes. Consequently, combinations of these ssp. longum BB536, L. plantarum R1012, and L. lactis ssp.
probiotics are commonly used to support metabolic health lactis R1058. Since this study focused on the adverse effects
in patients. However, a challenge remains in identifying and safety of high-dose probiotic administration, the other
19
the specific probiotic strains that are most effective for a factors measured are not relevant to this paper. A study
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6,19
broad population. The domino effect observed in many showed that yogurt containing L. acidophilus LA-5 and
studies suggests that the addition of Lactobacillus and/or B. lactis BB-12 did not significantly reduced body weight,
Bifidobacterium increases the abundance of the phylum BMI, or waist circumference in obese individuals on a
Bacteroidetes (Bacteroidata), which in turn enhances gut hypocaloric diet. Despite the absence of improvements in
biodiversity and promotes the production of SCFAs. 6,11,13 anthropometric parameters, the study suggested potential
SCFAs – specifically butyrate, propionate, and acetate – benefits for lipid profiles and insulin sensitivity. The lack of
help mitigate the harmful effects of accumulated visceral effectiveness may be due to probiotic strain survivability
adipose tissue on the liver. Acetate, in particular, binds to and participant adherence. 24
SCFA receptors, which may lead to the downregulation of
lipogenic genes. This simplified mechanism offers insight 5. Limitations
into the positive effects of probiotics, with speculation that This systematic review provides valuable insights but
these processes could help reduce insulin resistance. As has limitations and unresolved key issues that must be
a result, SCFAs are increasingly being measured as a key acknowledged. Addressing the challenges outlined below
parameter in obesity treatment. 6 through standardized methodologies and larger, well-
As mentioned previously, an increase in the phylum controlled studies is essential for improving the reliability
Bacteroidetes is associated with positive effects, alongside a and applicability of the findings.
decrease in Firmicutes. The relationship between these two Study heterogeneity. The variability in sample
phyla plays a crucial role in dysbiosis, which refers to an populations, methodologies, and intervention designs
imbalance of species within the gut microbiota. Dysbiosis, makes direct comparisons challenging. As discussed by
often characterized by the Firmicutes/Bacteroidetes ratio, Glasziou and Sanders, differences in study protocols
29
has been used as a parameter to assess the diversity of can lead to inconsistencies in reported outcomes. This
species in the gut, particularly in the context of obesity and heterogeneity ultimately limits the generalizability of the
metabolic health. 9,13,18 findings.

Volume 2 Issue 2 (2025) 42 doi: 10.36922/mi.8358