The nutrition meta thread: principles for a healthier life style

I have been told that my nails are weak due to eczema on the nail bed. For the last month or so I have been doing 30-40 minutes of strength work 5 mornings a week, followed by whey isolate and dextrose shake.
My nails are much stronger. Is this just fluke? or is there something in the shake? It’s the only thing I’ve changed…