Marc Pacchioli, known as Crophugger on Twitter, has written an excellent post on secondary plant metabolites on HubPages: Natural Plant Chemicals: Vital Nutrients for a Healthy Diet, Natural Chemical Arsenal, or Both?
What are these chemicals that plants produce? What are they for? For the answers to these and many more questions about plant secondary metabolites, check out the teaser below and continue on to read Marc’s full post.

Green potato with solanine molecule. Images from Simply Recipes and Wikipedia.
A discussion about the secondary chemicals naturally present in fruits and vegetables, indeed in most sedentary or slow moving forms of life on earth including fungi and sea sponges, usually is immediate cause for raised eyebrows and furtive glances, especially in non-scientific circles.
By secondary plant metabolites, I mean the chemical by-products that are produced by primary plant metabolism. Primary plant metabolism involves the essential chemicals of life i.e.; carbohydrates, proteins, fats and chlorophyll that are directly involved in plant growth and development.
Secondary plant chemicals were, up until recently, thought to be either plant waste products or defensive chemicals for example, solanine, which is an alkaloid present in that green potato skin that you have been told not eat since you were a child, with good reason, it’s a nerve toxin and at high doses can induce sickness or even death. A 160 pound adult would probably need to eat several pounds of green potatoes to experience symptoms of dry mouth, heart palpitations and possibly delirium, a higher dose could cause paralysis and even death.
For a really good discussion about natural vs. synthetic toxins and the Ames test, you might check out
http://pipeline.corante.com/archives/2002/07/30/the_ames_test_and_the_real_world.php
I haven’t been able to find a cite for this, especially since it’s politically incorrect, and buried under the trash that litters the web, but Ames has been cited as saying he very nearly regrets developing what is now called the Ames Test (in his honor). His regret: since you can find nearly anything with the test, you can create bogus consumer scares with nearly anything.
Which is of course the culture we live in today — what might alternatively be called The Scare of the Month Club.
Wow, that Ames video at the bottom of the post is great. What he conveyed in a few minutes–nicely done.
Thanks for the tip on this. I often tell people about coffee, and they don’t appreciate hearing it. Heh.