Contrary to much of the marketing hype, exogenous ketones inhibit fat loss. Ketones generated from the person have the following characteristics (Brianna J. Stubbs, Pete J. Cox, Rhys D. Evans, Peter Santer, Jack J. Miller, Olivia K. Faull, Snapper Magor-Elliott, Satoshi Hiyama,3 Matthew Stirling, and Kieran Clarke. On the Metabolism of Exogenous Ketones in Humans. Front Physiol. 2017; 8: 848.):
The metabolic phenotype of endogenous ketosis is characterized by lowered blood glucose and elevated Free Fatty Acid (FFA) concentrations, whereas both blood glucose and FFA are lowered in exogenous ketosis. During endogenous ketosis, low insulin and elevated cortisol increase adipose tissue lipolysis, with hepatic FFA supply being a key determinant of ketogenesis.
Ketone bodies exert negative feedback on their own production by reducing hepatic FFA supply through βHB-mediated agonism of the PUMA-G receptor in adipose tissue, which suppresses lipolysis (Taggart et al., 2005).
Exogenous ketones have similar effects.
Exogenous ketones from either intravenous infusions (Balasse and Ooms, 1968; Mikkelsen et al., 2015) or ketone drinks, as studied here, inhibit adipose tissue lipolysis by the same mechanism, making the co-existence of low FFA and high βHB unique to exogenous ketosis.
If your goal is weight loss from your body, exogenous ketones are probably a poor choice.