They all use the same U-100 scale, where 1 unit equals 0.01 mL, so a given dose is the same number of units on any of them
There are companies that do intracellular NAD testing
B12/MIC combines vitamin B12 with three lipotropic compounds (Methionine, Inositol, and Choline) which help support fat metabolism, liver detox, and energy production
For example, skin may start to look brighter or feel smoother
Here are some other ways to help increase levels of glutathione, along with taking care to optimize vitamin D: limit alcohol consumption decrease exposure to POPs increase intake of other antioxidants to decrease overall oxidative stress increase intake of nutrients that promote glutathione production, such as NAC (N-acetylcysteine), 1000 mg/day, whey, or SAMe get enough magnesium and selenium in the diet, as both are necessary for glutathione production foods such as almonds, cruciferous vegetables, and even alcohol-free beer have been shown to raise glutathione levels, as has meditation