Your choice affects onset time, bioavailability, and practical convenience
Immunity (2019) 51(4):671681.e5
A 2019 study found sublingual B12 supplements (aka the kind you put under your tongue) were even more effective than B12 shots
Kamali S
Spirulina platensis in ovo injection enhanced the expression of genes associated to immunity, antioxidants, and hatchability in quail chicks ( K-strain White Cornell Leghorns and broiler chicks grown to ages of seven and three weeks, respectively, on diets containing varied concentrations (10, 100, 1,000, and 10,000 ppm) of Spirulina platensis exhibited higher body weights than control birds ( Spirulina platensis per kg of feed, Cobb broiler chickens growth performance, blood parameters, biochemical changes in serum, and microbial load could all be improved ( Dietary supplementation of Spirulina at 10g/kg of diet showed significantly higher body weight gain and, consequently, linear improvements in FCR was observed in Cobb broilers during 35 days experimental period
The authors of one trial (95) included in the above-mentioned meta-analysis (89) noted that little cognitive decline was observed in the placebo group over their two-year trial, which may have limited their power to detect an effect of the B-vitamin intervention (95)
