Vitamin C 556% - Vitamin c does have an impact on sleep quality, with studies showing that people with higher vitamin c levels report a deeper sleep. However, most of this data is correlative, meaning that it could be other factors like, healthy diet as a whole. That said it's a fine inclusion in emergen zzzz nighttime sleep aid, just not the most important vitamin to focus on.
Vitamin D 31% - Almost 50% of adults in the US have a minor deficiency of vitamin d, and this has been shown to increase the likelihood of sleep disorders. As such, it's a good inclusion. And one that does also make it into better sleep aids.
Calcium 4% - Calcium is a relatively pointless inclusion at this dosage, as a supplement it does work for a lot of people as it's a common mild deficiency and it's essential for your bodies own production of sleep hormones, but as mentioned 4% of your RDI will do little to nothing to change that. It is included in a much higher dose in better sleep supplements.
Magnesium 14% - magnesium has been shown to function as a sleep aid, however, the relatively low dosage of 60mg in Emergen zzzz nighttime sleep aid is well below the 300mg that has been shown to work as a supplement. Whilst it is possible that if you have a very small deficiency that this could be of benefit to helping get a restful nights sleep, it's not going to make much difference in 90% of cases. As a result it's quite common in better sleep aids in the correct dose.
Zinc 18% - Zinc is a fine inclusion in that it's part of how your body regulates hormones and stress, meaning it can help with you sleep naturally, generally we'd like to see a higher dose from a supplement however.
Manganese 22% - Manganese is a decent inclusion, the dose is a little low, it has been shown to be one of the bodies essential nutrients for the production of GABA which is part of the chemical process that tells you it's time to sleep naturally. This is fine, it's not a common deficiency though and most people get enough.
Sodium 3% - too small of a dosage to have any impact.
Potassium 4% - too small of a dosage to have any impact.
Melatonin 3mg - Melatonin is an effective sleep aid, in many countries it's a prescription option and it does work, 3mg is the lowest effective dosage and won't necessarily work for everyone, but should help most people get to sleep more easily. Melatonin itself is the natural hormone that your body produces to let you know it's time to sleep. Typically it works in around 30 mins, and is the backbone of most natural sleep supplements and is a good inclusion for emergen zzzz nightime sleep aid.