What do protein bars and your gas pump have in common? Hexane!
Hexane is a byproduct of gasoline. It is used as a solvent for glues (rubber cement, adhesives), varnishes, and inks, and others
You might be surprised to know that hexane is also used to extract edible oils from seed and vegetable crops - primarily soybeans. And that, according to the Environmental Protection Agency (EPA), short-term exposure to hexane at high doses can affect the central nervous system. Neurotoxic effects have also been demonstrated in animal studies.
Manufacturers of natural foods use only expeller-pressed oils and fats that do not involve the use of hexane in the crushing process. However, the resulting "residual soy meal" is used in many soy protein powders that are turned into cereals, bars, smoothies, and other foods touted as "natural."
So how can you protect yourself against hexane exposure? Avoid all "conventional" processed soy foods, including foods made with hydrolyzed plant protein and soy protein isolate/concentrate. And when you do eat soy products, opt for those not processed with hexane, including fermented soy milk, fermented tofu, miso, tempeh, and soy sauces.