Yes, the Dose Really Does Make the Poison (Skeptoid Blog)

A frequent discussion I’ve seen (generally on twitter, and in some of the negative popular press articles about rapamycin) is around the possible side effects (or even the first effect approved… such as immune suppression).

I still see people disparaging rapamycin, or other potential longevity drugs, with lists or descriptions of terrible side effects, but with no mention at all about the dosing levels and dosing schedule (daily/weekly?) associated with those side effects, and not mentioning the frequency of these side effects.

We see this sometimes even here in our forums. So this is just a post for people to link to whenever someone does this… talks about side effects without talking about dosing or dose schedule.

Yes, the Dose Really Does Make the Poison

One thing that frustrates me in conversations about “harmful chemicals” on Skeptoid and elsewhere is when individuals display a complete lack of understanding of dosage. This comes in two forms.

The first form is the passive argument that completely omits"dosage" from their point entirely. I can never tell if someone overlooking dosage is being uninformed or dishonest; part of me wants to give the benefit of the doubt, but another part of me finds it hard to believe they’ve never encountered such a basic concept as dosage. The second is the active argument that “Dosage doesn’t matter” or “dosage is irrelevant”, which is often used to imply that some chemical or other isso badthat isalways should be avoided. Invariably this is directed at some chemical that millions of people ingest everyday without obvious harm.

Both of these arguments fall flat in the face of scrutiny. Dosage very much matters , because all chemicals are toxic . This is not a sweeping generalization; it’s just a basic fact of chemistry. Toxic is a word you hear people throwing around a lot without any actual sense of definition or context, i.e. “toxic chemicals”, but there is no such thing as a “non-toxic chemical”; everything is a chemical and all chemicals have a point where they become toxic to the human body.

The term for the dose at which a chemical becomes dangerous or deadly is toxicity . In chemistry they also refer to a chemical’s “lowest published toxic dose”, or Toxic Dose Low (TDL), the point at which a chemical will start to have adverse effects on the body. The point at which a chemical becomes toxic enough to kill is called its Lethal Dose Low (LDL). Every chemical has a TDL and a LDL, though the levels vary greatly from chemical to chemical.

Consider water, the most common and important ingredient in the things we consume. In debates about chemicals we skeptics love to bring up water (which irritates the toxic chemicals crowd to no end) because it’s an extreme and obvious illustration of the point: water, in large enough quantities, can kill. It has both a TDL and a LDL. And no, I’m not talking about drowning; I’m talking about water intoxication, which can kill you. And yet we drink it every single day.

Full article here:


I think your article possibly understates the danger of Dihydrogen Monoxide dosage. Please see the following and be aware!


I did not see any reference to thiscompoundin this story, did I miss it?

1 Like

Yeah - you missed it - last paragraph. Think a little April 1st coming up. :slight_smile:


Gotta love this … yes a very dangerous compound — we really do need to warn people about the dangers of dihydrogen monoxide.


That is one of the wildest unscientific articles I have read this year. First-rate conspiracy theory article.

“What are some uses of Dihydrogen Monoxide?”

“in cult rituals,
by the Church of Scientology on their members and their members’ families (although surprisingly, many members recently have contacted to vehemently deny such use),
by both the KKK and the NAACP during rallies and marches,
by members of Congress who are under investigation for financial corruption and inappropriate IM behavior,
by the clientele at a number of bath houses in New York City and San Francisco,
historically, in Hitler’s death camps in Nazi Germany, and in prisons in Turkey, Serbia, Croatia, Libya, Iraq and Iran,
in World War II prison camps in Japan, and in prisons in China, for various forms of torture,
during many recent religious and ethnic wars in the Middle East,
by many terrorist organizations including al Qaeda,
in community swimming pools to maintain chemical balance,”

Whatever the pros and cons of DHMO, this article is pure trash.


@desertshores you may find it trash, but it’s true.


Ha, I was half asleep while reading this… H2O, I get it. :smile:


Lots of people drown in it.