Mythbusting Pine Needle Tea Danger

Blame lawyers

Feb 26, 2026

Whenever I feel like stirring the pot on social media, I post a recommendation to drink pine needle tea. Within seconds the nannystate erupts with warnings that I’m going to cause miscarriages all across North America. It’s a great way to drive up my viewer numbers. Don’t judge - it’s a game I need to play to keep doing my passion of reconnecting people to nature. But if there really was any danger to pregnant women I wouldn’t post drinking this wonderful tea.

Thanks for reading Merriwether’s Substack! This post is public so feel free to share it.

Isocupressic acid

Yes, it’s a myth that drinking pine needle tea will cause miscarriages in humans. This foraging warning arose from studies taking place soon after the end of World War II using ponderosa pine needles (Pinus ponderosa) as browse for cattle. It was seen that a number of cows in the last third of their pregnancy spontaneously aborted when a large part of their food consisted of these needles. More research showed lodgepole pines (Pinus contorta) can also have a similar effect. Chemical analysis of these two needles identified isocupressic acid as the chemical culprit causing problems.

So, pretty terrible, right? Well…no. Feeding ponderosa and lodgepole pine needles to other animals had no abortive effects and even in the case of cattle, it required 200 mg/kg body weight per day of isocupressic acid to have this effect. To reach that level requires the pregnant cow to eat 3-5 pounds of fresh needles every day for days in a row.

Pine’s Danger to Humans

Now let’s turn to humans. There is NO documented scientific evidence of isocupressic acid having an abortive or other negative effect on pregnant women or any other human without consuming gallons of ponderosa pine needle tea for days. However, science doesn’t matter when it comes to our legal system. If a pregnant woman drinks pine needle tea and their fetus develops any sort of issue, regardless of the cause, she can very easily sue whoever told her/sold her the “safe” pine needles, resulting in a very expensive lawsuit for the defendant even if he/she wins the case. This is why there’s all these warnings on pine needle tea from any pine that pregnant/nursing women shouldn’t consume it. The seller is adding the warning to protect themself against a fake threat.

Pines of the South

In the southwest/southeast we have Loblolly pine (Pinus taeda L.), Longleaf pine (Pinus palustris Mill.), Eastern White pine (Pinus strobus), Pinyon pine (Pinus edulis), Shortleaf pine (Pinus echinata), and the Slash pine (Pinus elliottii). None of these contain any notable amounts of isocupressic acid, regardless of what you may read from some stranger on the internet. Meanwhile, they all contain useful amounts of vitamin C.

As more and more AI-written foraging articles appear on the internet, myths such as this will be repeated over and over. Back in my computer programming classes this was referred to as GIGO “Garbage In, Garbage Out”. When the initial data is wrong, the computer can’t give you the right answer. But when it comes to foraging, I can…at least while people allow me to!