Either all at once, or over a lifetime?
You can easily kill yourself with a water overdose (and it’s actually fairly common),so yes.
Nutmeg was already mentioned - high doses can easily kill someone, sadly even without hallucinations simply by killing off ones liver and dying an agonizing death a few days later. The same goes for cinnamon, but with a much lower dose.
There are a few more, but I don’t want to give people too many ideas.
To make it short: Yes, possible,but it’s mostly a very slow death over multiple days that fucks you up really bad and is a horrible way to go.
It really depends on the herb but as a general rule you likely cannot. If you are cooking and decide to add double or triple or even 10x the herbs / spices then the recipe suggests you will be fine. The worse case scenario is that you make it taste bad. That being said everything is poison at high enough doses but for culinary herbs that is a huge dose. You will really have to force yourself to eat large enough quantities since it will taste very unpleasant.
There are plenty of other plants that are more dangerous.
Generally speaking, I think you’re right. Herbs and spices are safe. But I wanted to add a caveat: caution is always a good idea. You could damage organs like the liver or kidneys, specially if you have an issue with them.
For example, too much turmeric can result in liver damage: https://www.jeffersonhealth.org/your-health/living-well/the-trouble-with-turmeric-associated-liver-injuries
Another example: Rooibos tea is awesome but there’s this guy who drank a bit too much, and ended with liver failure: https://pmc.ncbi.nlm.nih.gov/articles/PMC4435260/#B4 There are more reports of hepatoxicity here: https://www.mskcc.org/cancer-care/integrative-medicine/herbs/rooibos-tea
Caution is a good idea but as long as you aren’t drinking gallons of tea or taking tons of herbal pills you should be fine.
Nutmeg is poisonous in high doses and can lead to hallucinations, seizures, and other complications.
You can overdose on water, so I’d say “yes.”
Tamil proverb says
அளவுக்கடந்தால் அமிர்தமும் நஞ்சு
It’s emphasizing that even the most potent, life-giving elixir can become poisonous if taken in excess.
