Questions I missed: Solubility of our powdered ingredients

In this post, Lalla writes: If the solubility is 0.5% at 25°C, does it mean if we dissolve a higher concentration at say 35°C the allantoin will crystallize as it cools down? If I try to dissolve MSM and allantoin and caffeine in water, will their respective solubility decrease because of the other ingredients?Solubility is generally measured…