I don't think so! I'd bake some soaked, raw walnuts on a low-ish temperature, like 200 degrees, if you really wanted to be paranoid
Walnuts (well, most nuts in general), are extremely high in polyunsaturated fats which oxidize very quickly and turn rancid when exposed to high levels of heat for an extended period of time and this is in general, not a good thing since rancid fats place quite a bit of oxidative stress on your body.
Doing it once in a while may not cause much harm, but if you're doing it regularly, I would cut the habit out. If I eat nuts, I'm eating them raw for just this very reason. Just my two cents though, and take it with a grain of salt.
Oh, who cares. For an occasional treat, it sounds delicious.
F 28/5'4/100 lbs
"I'm not a psychopath, I'm a high-functioning sociopath; do your research."
“I'm glad mushrooms are against the law, because I took them one time, and you know what happened to me? I laid in a field of green grass for four hours going, "My God! I love everything." Yeah, now if that isn't a hazard to our country..."
― Bill Hicks
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