It depends on your health goals and needs
Water research 2020 PMID: 32004911 The Phytomanagement of PFAS-Contaminated Land Evangelou MWH, Robinson BH International journal of environmental research and public health 2022 PMID: 35682401 Co-occurrence of odor-causing dioxanes and dioxolanes with bis(2-chloro-1-methylethyl) ether in Huangpu River source water and fates in O(3)-BAC process Wang C, Yu J, Chen Y, et al
GHK-Cu and BPC-157 in Accelerating Tissue Repair: A Comprehensive Review
Future of IV glutathione and B-12 shots still unsettled in California Crystal A
Having the shot directly in to the muscle allows the liquid vitamin to enter the blood stream quickly, bypassing the digestive system and the gastric acids and many other obstacles anything which is taken via the mouth has to go through to reach the small intestine, for re absorption
However, although weight loss was observed in some studies, it did not occur in all studies (2)