Probiotic Supplementation

Samar Elshahat Saleh et al. (2026) · Scientific reports

This double-blind randomised trial with 72 people who have moderate to severe chronic kidney disease explored whether a daily Lactobacillus plantarum probiotic could slow the decline of kidney function. Chronic kidney disease affects about 10% of people worldwide, and in moderate stages (3 and 4) there are few ways to slow it. The gut-kidney axis is the idea that waste molecules produced by gut bacteria, such as indoxyl sulfate, can burden the kidneys, so changing the gut bacteria with a probiotic might help. The main yardstick was eGFR (estimated glomerular filtration rate), a blood-test estimate of how much blood the kidneys filter each minute. The study ran at a nephrology centre in Mansoura, Egypt, between May and November 2025. Participants were adults with eGFR between 15 and 59, mostly men around 60 years old, and many also had hypertension or diabetes. They were randomly assigned to a daily capsule of 10 billion L. plantarum bacteria (37 people) or an identical dummy capsule (35 people) for six months, while all continued standard kidney care. Neither patients nor staff knew who received which capsule. Kidney function moved in opposite directions. eGFR rose by a median of 4.85 in the probiotic group (30.8 to 36.1) and fell by 1.5 in the placebo group (31.7 to 29.7); after adjusting for starting values the probiotic group's eGFR was 7.72 higher (95% CI 5.63 to 9.82, p < 0.001). Serum creatinine fell by 0.3 mg/dL with the probiotic and rose by 0.1 with placebo, and measured creatinine clearance rose by 7.8 mL/min versus a 4.9 fall. The result held in stage 3 and 4 and in people with and without diabetes. Urine indoxyl sulfate did not differ between groups, and protein in the urine rose in both. Nobody in the probiotic group had disease progression versus three people on placebo (8.6%, p = 0.11), and no side effects were reported. The authors conclude that the probiotic may improve eGFR and that its effect did not appear to work by lowering indoxyl sulfate. Limits include a single centre, only six months, no measurement of gut bacteria or inflammation, a urine rather than blood toxin test, kidney function estimated from creatinine rather than measured directly, and several analyses done after the fact, so the results are preliminary and need confirmation in larger, multi-centre trials with longer follow-up.

Karolina Osowiecka et al. (2025) · Nutrients

This double-blind randomised study with 64 women who have Hashimoto's thyroiditis explored whether adding a probiotic to nutrition education changes how they feel and function. Hashimoto's thyroiditis is an autoimmune condition in which the immune system attacks the thyroid gland, the gland in the neck that governs metabolism, and it is usually tracked through antibodies called anti-TPO (anti-thyroid peroxidase). Probiotics are live bacteria taken as supplements; the one tested here, Lactiplantibacillus plantarum 299v (Lp299v), is a strain studied for gut symptoms, and the researchers asked whether it adds to the benefits of dietary education. The study took place at a dietetics clinic in Warsaw, Poland. All participants were women aged 18 to 64 with stable thyroid function, most taking levothyroxine. For 12 weeks everyone attended six individual sessions with a dietitian and received a personalised menu. Half also took one Lp299v capsule daily (10 billion bacteria), while half took an identical dummy capsule. Quality of life was scored with the ThyPROpl thyroid questionnaire (0-100, lower is better) and gut symptoms with the GSRS (Gastrointestinal Symptom Rating Scale); blood pressure, body composition, diet quality and anti-TPO were also measured. Both groups reported better quality of life, but the probiotic group improved more. Overall scores dropped by 25.0 points with the probiotic (from 60.94 to 35.94, p = 0.006) versus 14.9 points with placebo (from 54.69 to 39.84, p = 0.043), and the probiotic group improved significantly in 12 of 14 areas while the placebo group improved in 3 of 14. Constipation, abdominal pain and reflux scores favoured the probiotic, and blood pressure, especially systolic, fell more in that group. Anti-TPO antibody levels and body mass index did not change in either group (the immune marker itself did not improve). Diet quality scores rose in both groups, from about 11 to 18.5 points with the probiotic and from about 12 to 19 with placebo, showing that the education alone changed eating habits. The authors conclude that education plus Lp299v improved quality of life and blood pressure without changing the thyroid antibody marker, and suggest that longer and larger trials are needed. The evidence has clear limits: a single clinic, participants recruited through social media, self-reported food diaries, a placebo arm with only about 57% statistical power for overall quality of life, and improvement in both arms, so a placebo or education effect cannot be ruled out. The results apply to euthyroid women with Hashimoto's over 12 weeks and say nothing about long-term outcomes.