Heat Stress Additives

Summer is once again here and I have already received three calls regarding diet changes in anticipation of summer heat waves. Naturally, when it comes to additives the first selection has always been vitamin C and sodium bicarbonate.   But, I have a question for all of us… If we were to pick only one of the two additives (vitamin C or sodium bicarbonate), regardless of cost, which one would you prefer based on expected efficacy against heat stress? Please, do leave a comment!