[Lazare]

Canola oil contains low amounts of trans fat, comparable to all other oils, and while heating it does increase the amount, it's slow. Using canola oil in a deep fryer for 7 hours per day for 7 days resulted in boosting the trans fats from 2.4% to 3.3% by weight; the canola oil in the beyond burger will be at the low end of the range. Meanwhile, actual beef fat is around 5% trans fat, meaning that if trans fats are all you care about, the beef burger probably has more trans fats than a beyond burger.

(Whether beef tallow is actually better or worse than canola oil is complex, and some suggest trans fats in beef fat are healthier in canola, etc., but OPs naive "don't swap out a beef burger for a beyond burger because traaaaaans" seems a bit simplistic. Canola oil doesn't have much, and it's comparable to other sources of oil, including animal fats.)

[orwin]

I thought all vegetable oils were bad when heated (and also provide few nutrients, unlike animal-based grease/fat).

[Lazare]

If you heat them past the smoke point, yes, they lose a ton of nutrients and become quite unhealthy. In normal use, no, not really. The impact of heating them is quite small. And comparing them to animal fats...they're clearly slightly better in some ways, but slightly worse in others. How you balance those factors...I don't think we remotely have good data on yet.

For now I'd just try and eat in moderation and look askance at people making sweeping assertions about any food being all good or all bad.

(On the other hand, we have much better data about the environmental impact of vegetable versus anaimal calories.)

[liamcardenas]

I think the trans fat thing was a metaphor (impossible burger doesn’t even have canola oil). His main point that the beyond burger is not very nutritious — it’s just protein isolate and oil with a bit of fiber and flavoring.