Three Kasivit products sold together: Probiotic 40 Billion with Prebiotics, Magnesium Glycinate and 5-HTP.
These are three separate products that are also sold individually. The combination has not been studied, and none of the products is a treatment for insomnia, gut disorders or any other condition. The science below explains why these three ingredients are often paired: 90% of the body's serotonin is produced in the gut, and serotonin is the direct precursor to melatonin. That is a plausible biological link — it is not a guarantee that this combination will improve your sleep. If sleep trouble is persistent, speak with a doctor.
Probiotic 40 Billion with Prebiotics — per the confirmed label, a 2-capsule serving provides 40 billion CFU in a proprietary blend of four strains (Lactobacillus acidophilus La-14, Bifidobacterium lactis Bl-04, Lactobacillus plantarum Lp-115 and Lactobacillus paracasei Lpc-37) with the manufacturer's MAKTREK delivery system, plus fructooligosaccharide (24 mg) and a marine polysaccharide complex (60 mg). Probiotic effects are strain-specific. In a meta-analysis of 53 trials in adults with irritable bowel syndrome, particular probiotic combinations or strains appeared to help global symptoms and abdominal pain, but definitive conclusions could not be drawn (Ford 2018), and in a meta-analysis of 63 trials probiotic use was associated with a lower risk of antibiotic-associated diarrhea (Hempel 2012). The link between gut microbiome composition and serotonin production is supported by animal and in vitro studies; large-scale human trials are ongoing. No study of this product is cited.*
Kasivit Magnesium Glycinate Capsules — per the confirmed label, a 3-capsule serving provides 275 mg of elemental magnesium from 2,500 mg of magnesium glycinate. In a 4-week trial in 155 adults reporting poor sleep, 250 mg of elemental magnesium a day as bisglycinate lowered Insomnia Severity Index scores slightly more than placebo (−3.9 vs −2.3 points), and the authors called the effect size small (Schuster 2025). The US upper limit for magnesium from supplements is 350 mg a day for adults; count magnesium from all supplements. No study of this product is cited.*
Kasivit 5-HTP — 5-hydroxytryptophan from Griffonia simplicifolia seed extract, in vegetable capsules. 5-HTP is the immediate precursor to serotonin; after serotonin is synthesized it can be converted to melatonin by the pineal gland. In a meta-analysis of 6 randomized trials, 5-HTP improved mood scores compared with placebo, with low certainty of evidence (Shaw 2002); evidence specifically for sleep is limited to small trials. 5-HTP can interact with antidepressants and other serotonergic medicines — do not use if you take an SSRI, SNRI or MAO inhibitor without first asking your prescriber or pharmacist. No study of this product is cited.*
Each product is also sold individually on its own page.
Bundle price of $76.49 vs. $89.97 when the three products are bought separately.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
