3,5-Diiodo-L-Thyronine

Also known as 3,5-T2 or T2.  Like 3,3′-diiodo-l-thyronine, it’s a breakdown metabolite of the active thyroid hormone, T3.  Animal data suggests it can reduce body fat accumulation by reducing oxidative stress and altering hepatic (liver) fat metabolism - without inducing thyrotoxicity.  This is why it’s included in several weight loss supplements, although a) there’s no controlled human data on its use for this purpose; and b) there is little available info on its oral pharmacokinetics (or dose) - the animals in the studies were injected with 3,5-T2, not fed/gavaged.