Machalei Sakana – Blessing on foods forbidden due to danger:<a href="#_ftn1" name="_ftnref1">[1]</a>
A blessing is not to be recited over foods which are forbidden to be eaten due to danger. This applies whether the food was prohibited by the Sages due to danger [i.e. fish and meat mixture], or is personally forbidden to the person [i.e. lethally allergic to dairy]. However, if the food is simply generally not healthy or recommended [i.e. high in sugar or salt] then a blessing is to be recited upon eating or drinking the food. &nbsp;
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<a href="#_ftnref1" name="_ftn1">[1]</a> See Michaber 202:4; Seder 7:9; Luach 10:9; Admur 196:5; 204:15; Maharam Shick O.C. 260; Piskeiy Teshuvos 196:1 and footnote 13; Sefer Shemiras Haguf Vihanefesh [Lerner] Mavo Chapter 10 *Source sheets

Shulchan Aruch HaRav | Is a Bracha to be recited when eating an unhealthy food, or any food forbidden due to health reasons

Machalei Sakana – Blessing on foods forbidden due to danger:[1] A blessing is not to be recited over foods which are forbidden to be eaten due to danger. This applies whether the food was prohibited by the Sages due to danger [i.e. fish and meat mixture], or is personally forbidden