Nails can be stored at room temperature for 20 years and still yield enough DNA for forensic analysis.
I'm still using nails that are over 2 years old with efficacy to compare against fresh nails.
Indeed, fresh nails elicit a more powerful response, but I have found that the older nails do indeed still elicit an effective response as well.
The 30 day recommendation for nails is based on the light component of DNA.
It has been shown that DNA both absorbs and emits photons.
If you were to take a DNA strand and isolate it in a sealed chamber, and inject photons, they will be attracted to the DNA.
If you then remove the DNA, and observe the now empty chamber, you will find that there is still a photonic imprint of the DNA strand that will last for 30 days.
These experiments were conducted by both Russian scientist and Dr. Luc Montagnier, the same nobel prize winning scientist that has cloned DNA using only water and 7 Hz.
So, if the light aspect of DNA is adding value, and is responsible for the extra effect felt with fresh nails, then it would behoove one to continue to replace the nails within 30 days if possible.
If you have a sample from someone that you can not get fresh samples from regularly, do not throw out the nail, and continue to use it.
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