Does LSD "stay" in your fat storage and then "returns" back? This rumor was told me by a very anti-drug person. A stance I agree with only lightly. The rumor was that when you take LSD, it stores itself in your fat storage, and then returns back in 3-6 months, returning back meaning there would be another series of effects of LSD (the trip). Is this true? I highly doubt it. However, what I don't know, if the body is processing (burning?) fat _and then_ processing substances (such as the rumoured LSD) found in fat stores.

I've heard this rumor for years, both from pro- and anti-drug people, and it is not true. According to this review of LSD's pharmacology, its half-life in the body is about 5 hours, with it being completely cleared within about 15-28 hours. There is no evidence that it accumulates long-term in fat, cerebrospinal fluid (CSF), or anywhere else in any pharmacologically significant quantity.

Reference:
"The Pharmacology of Lysergic Acid Diethylamide: A Review" _CNS Neurosci Ther._ 2008 Winter; 14(4): 295–314. PMID: 19040555 DOI: 10.1111/j.1755-5949.2008.00059.x