Supplements improve consumers' health and well-being. Oleogels are fat substitutes that offer nutritional and structural improvements to foods. This study aimed to formulate and observe chocolate's structural differences and properties supplemented with different premixes for immune support and oleogel based on Brazil nut oil. Six 60% dark chocolates were produced using oleogel as a partial substitute for cocoa butter (with and without premixes), and premix 1 (vitamin D3, vitamin C, and zinc) or premix 2 (vitamins D3, C, A, E, zinc, and selenium). Texture, rheology, thermal analysis DSC, color, water activity, moisture, pH, and fat profile were determined. The results revealed that the whiteness index was higher for the oleogel and supplemented products. The use of oleogel reduced the lipid content of the products by 5% and saturated fatty acids by 13%. DSC showed changes in the melting and crystallization profiles for the supplemented products. All samples showed thixotropy, and the yield value was significantly different (