Sodium bicarbonate (called baking soda in USA) was recently reported as a possible cure for autoimmune diseases.
The study was on rodents but some healthy student volunteers were also followed for 2 weeks in a small human study. After taking 0.5 tsp bicarb dissolved in water every day for that time their immunity was pronounced to be improved. I can report that following this regime for 4 weeks has produced no noticeable effect. Symptoms are unchanged. As ever, one wonders whether those humans studied had a healthy diet/lifestyle to begin; otherwise the bicarb could simply be countering an acid diet.