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Review of "Your Brain on Food"

By Gary L. Wenk
Oxford University Press, 2010
Review by Shelly Marshall on May 18th 2011
Your Brain on Food

Why did witches once think they could fly? Why is it so hard to give up smoking? Why do muscles contract? Why do patients with Alzheimers have trouble paying attention to things that might harm them?  And how did Coca Cola really get its name?

These might be questions that you didn't know you wanted answered, but once into Wenk's book, you will be answering all kinds of questions you didn't know you asked. This book is a delightful introduction to basic neuroscience, plant biology,  and how drugs affect your brain which in turn affects your thinking and behaver.

Chapter One is the introduction and begins with a basic 101 lesson : anything you consume affects the way you think and feel. The brain contains over 100 known neuro-chemicals (and there are probably as many left to discover), and how substances, whether food, medicine or recreational drugs, influence the chemicals in your brain. The book is not a boring list of formulas and foreign words but rather an entertaining brief on what's happening in your noggin. And even if you do not understand everything the author writes (yes its complicated), you will leave with a few tidbits of knowledge that are sure to impress your friends.

Gary Wenk explains that plants produce the chemicals that affect our brains. The chemicals we call drugs. But drugs are not good or bad. They are nutrients, aka chemicals, nothing more or less. Yet, the author points out, plants produce chemicals that affect our brain only because we share an evolutionarily history. Because we evolved together, we have the ability to produce similar chemicals that inter react with each other from one celled amoebas to insects, plants, animals and homo sapien. However, in a Star Trek scenario, the chemicals that kill us (like venom from a cobra), probably would not kill a Martian because his neuro-transmitters evolved elsewhere and the venom most likely could not react with his bodily system.

Fat soluble "drugs" (remember that drugs are nutrients)  enter the brain quickly like vitamins A, D, E, and K as well as coffee and nicotine, also fat soluble. Sugar is a powerful drug but then it would have to be as the brain cannot live for more than a few minutes without glucose. When sugar levels (glucose) decrease after a meal, you become hungry. The hunger has you seek out food that will feed the brain and hopefully that is something sweet.

The brain gets easily habituated to some nutrients like coffee and nicotine but we can never simplify the effects because drugs affect people in a complex way. For instance, when you have a fever, aspirin will bring it down, but it won't cool you off on a hot day.

Chapter Ones ends letting the reader know that this book is only  a summery barely scratching the surface of what goes on in this brain of ours. Nevertheless you will learn more than you thought you wanted to know.

Chapter Two examines "Memories,  Magic, and Addiction" and delves into poisonous plants that get you high! Exploring these toxic plants is a bit difficult because they are refereed to by their scientific names, common names and occasionally their nic names--following what chemical is what becomes a bit cumbersome if not highly entertaining. Wenk deals with henbane, jimsomweed, mandrake (the stuff of Harry Potter) and even deadly nightshade along with the mention of a snake or two.

The author gives a colorful account of how Voo Doo dolls work by playing on fears and expectations. Through a series of sympathetic nervous system triggers and other reflexes, a victim can appear to be dead, buried, and rise later, extremely annoyed at what has happened... all the makings of Zombie movies for Hollywood.

In a witty manner, the author continues with wild tales of of nude witches riding brooms under the influence of Datura and potash. He includes in his tales, stories of Amanita mushrooms and how the Vikings used them when invading Ireland. The psychoactive ingredients are very stable in this mushroom and can be used up to 4 times. That meant that Vikings undoubtedly drank the urine of one who used it and were able to get high for multiple battles on one dose! It makes one wonder who initially discovered this fact!

Chapter Two ended with a discussion on smoking and how nicotine is the most addictive drug currently used by humans. I can attest to that!

Can chemicals determine whether we are happy or sad?" Wenk asks in Chapter Three. The reader is then introduced to catecholamines that may in fact determine our emotions. The discussion of imported neurotransmitters began to lose me although the author does pepper the discussion with some interesting facts. But I am not a brain surgeon and this is not a textbook and there is only so much talk of norepinephrine, dopamine, tyrosine, levodopa, tyrosine hydroxylase, amino acids and cofactors that one can take in a single paragraph!

The reader does learn that it was suggested that Adolph Hitler's paranoia at the end of his reign was probably do to his amphetamine use. There are a number of plants in the wild that are amphetamine like from mahuong to khat, an African plant, and even a cactus called mescaline which of course will be well known to baby boomers.

Some spices also spice up the brain such as nutmeg which contains an ingredient not unlike mescaline. But alas it takes a whole can to produce a slight high and its use can cause psychosis accompanied by diarrhea. So who is using that! Other  spices of interest would be saffron, fennel, dill, and cinnamon which also contain psychoactive substances.

An interesting tidbit for those in the medical field is that every drug of abuse somehow enhances the dopamine uptake in the brain.

Filtering and dealing with all the bombardment of sensory information mankind now lives with is covered in Chapter Four. So how do we anchor ourselves in reality with sights and sounds and feelings coming at us from everywhere? It is not well understood but serotonin seems to be the main neurotransmitter that dribbles into our brain  during waking periods and keeps our feet planted firmly on earth. 

Although not stated emphatically, spiritually minded people might not like the serotonin explanation of religiosity. Wenk tells us that "extravagant" religious behaviors are associated with shrinkage of the right hipppocampus! One might be offended when he writes, "...for lack of any more precise way to quantify these experiences, neuroscientists often describe religious phenomena in terms of neurobiological processes..." but then he narrowly redeems himself by writing that perhaps scientists are observing "the a brain's response to an actual communication from God!"

Chapter Five is a treatise to marijuana and how we have endocannabinoids in our own brains.  Human brains have a large number of neurons that are affected by marijuana causing it to be nearly impossible to explain all that is going on with our brain on cannabis.

Chapter Six deals with GABA and how it turns on and off our neurons--which turns on and off parts of our brain. The effects of alcohol, barbiturates, bensodiazepines, and amino acids are explored.

Chapter Seven deals with sleeping and waking while Chapter Eight is a lesson on the evolutionary history of our neuopeptides and is the chapter that teaches about opiates and opiate-like neurotransmitters.

Chapter Nine is titled, "Brain Enhancement and Other Magical Beliefs" where Wenk destroys our cherished beliefs that somehow we can enhance the function of the brain as we age-- "it is impossible" he writes. I don't want to believe him. The products that we find on line that claim to do this are actually stimulants that enhance performance, not cognitive function. I still don't want to believe him. "Faster is not smarter," he points out.

Wenk takes away the promise of a truly anti-aging remedy for our brains. The very air we breathe, he says is aging us. Gingko Biloba and other plant extracts from herbologists only give us a placebo effect. Dastardly book, I say. You may not want to read it and have your hopes dashed--but then again, you might save a lot of money on "youth" potions.

                                                                Gary L. Wenk took a very complex subject and gave a playful yet informative account of how food (nutrients) affect our brains. Questions were asked that you didn't know you wanted answers to--and although you will have to read the book to find out what causes you to feel like you are being watched at times and why margarine might be good for the aging brain, I will tell you that Coca Cola did not (as is generally thought) get its name because it contained cocaine. Where did the name come from? You have an entertaining book to read to answer that one.


© 2011 Shelly Marshall


Shelly Marshall, B.S., CSAC is an Adolescent Chemical Dependency Specialist and Researcher. You can review her work at and