Sodium ions help control blood flow, blood volume, osmotic balance, and pH.
Drug addiction is a chronic disease characterized by compulsive, or uncontrollable, drug seeking and use despite harmful consequences and changes in the brain, which can be long lasting. These changes in the brain can lead to the harmful behaviors seen in people who use drugs. Drug addiction is also a relapsing disease. Relapse is the return to drug use after an attempt to stop.
Malnutrition is not having enough of the needed nutrients (not having a good diet, eating a lot of unhealthy food but still eating) this could be from either under consumption or over consumption. While under-nutrition is when someone eats an inadequate amount of food for an extended period of time (not eating enough food in general).