Rewire Your Brain: Think Your Way to a Better Life

advanced glycosylated end products
(AGEs). A visual example 
of AGEs is what happens when you roast the skin of a chicken. 
Unfortunately, AGEs cause far more destructive results than simply 
toughening the skin. They act like a chemical glue that attaches 
molecules to one another, causing what has been referred to as a 
cross - link
. Overcooked meat, for example, is cross - linked, which 
is why it is diffi cult to cut or chew. When your tissue has been 
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cross - linked, many metabolic processes become impaired. For exam-
ple, glycation (excess glucose) blocks protein from moving freely. As 
a result, the body ’ s membranes become blocked, which slows down 
neural communication. This glycation causes infl ammation. 
Sugars are refi ned carbohydrates that can increase free radical 
infl ammatory stress on the brain. A
free radical
is a molecule with a 
rogue electron that can rupture cell structure. After a series of reac-
tions, AGEs lead to free radicals and infl ammation. AGEs alter the 
structure and activities of proteins and also interfere with synaptic 
communication. Also, there is structural damage to the mitrochon-
dria, which are the energy factories in each cell that produce ATP 
(adenosine triphosphate) — the chemical energy fuel. 
The negative effects of glycation are not immediate, but over 
time the neurons are damaged. 
It is no wonder that high sugar consumption is associated with 
depression. Studies comparing the sugar consumption rates in coun-
tries such as Japan, Canada, and the United States fi nd that Japan 
has lower consumption rates as well as lower rates of depression. 
Because of the systemic ill effects of sugar, researchers were 
motivated to improve the methods of measuring its level in the 
body. The concept of glycemic load (GL) was developed at Harvard 
University in the late 1990s. The higher the GL of a food, the greater 
the expected rise in blood sugar and the greater the adverse insulin 
effects of the food. Long - term consumption of foods with a high GL 
leads to a greater risk of obesity, diabetes, and infl ammation. 
Researchers have shown that when people are given the amount of 
sugar in two soft drinks (75 grams of glucose), the free radical prod-
ucts of damaged fatty acids, called
isoprostanes
, rise by 34 percent 
in just ninety minutes after consumption. 
Mild isoprostane elevation has been associated with Alzheimer ’ s 
disease. Another blood marker of oxidative stress (free radical dam-
age) and damage to fatty acids is called
malondialdehyde
(MDA). 
Research ers have shown a relationship between increased GL and 
MDA. 
More than twenty 
- fi ve years ago, researchers from the 
Massachusetts Institute of Technology (MIT) found a 25 percent 
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difference between the IQ scores of children with high versus 
low consumption of refi ned carbohydrates (sugar and white fl our) 
(Schauss, 1984). The differences in glucose result in signifi cant 
costs to cognition and to the brain itself. Research at Britain ’ s 
Swansea University found that dips in blood sugar are correlated 
with poor memory, poor attention, and aggressive behavior. 
When researchers from Yale University gave twenty - fi ve healthy 
children a drink containing the amount of glucose found in most 
soft drinks, the rebound in blood sugar boosted their adrenaline to 
more than fi ve times their normal level for up to fi ve hours. Most 
of these children found it diffi cult to concentrate and were anxious 
and irritable. 
Similarly, researchers in Finland assessed the effects of sugar 
consumption on 404 children ages ten and eleven. They found that 
withdrawal, anxiety, depression, delinquency, and aggression were 
twice as frequent in those who consumed 30 percent more sucrose 
in the form of soft drinks, sugary snacks, and ice cream (Haapalahti, 
Mykk ä nen, Tikkanen, and Kokkonen, 2004). 
The conclusions are clear: High sugar intake is bad for your brain 
and results in signifi cant impairment of your ability to think clearly, 
maintain even moods, and behave effectively in a social situation. 
Keeping your blood sugar balanced and sustained is therefore criti-
cal for your brain to operate optimally.
The Amino Acid Cornucopia 
The biochemistry of your brain is dependent on obtaining specifi c 
nutrients from your diet. Certain amino acids are the crucial building 
blocks for neurotransmitters, which your body makes by synthe-
sizing these amino acids from the food that you eat. For example, 
L - glutamine is an amino acid found in foods such as almonds and 
peaches; when it is digested, your body synthesizes it into the neu-
rotransmitter GABA, which helps you to stay calm. Tyrosine, which 
is manufactured by your body from the amino acid phenylamine, is a 
building block for the neurotransmitters epinephrine, norepinephrine, 
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and dopamine. It is also an important building block of the thyroid 
hormone thyroxine. 
Choline, which is found in egg yolks, serves as the raw material 
for the manufacture of the neurotransmitter acetylcholine. Richard 
Wurtman of MIT noted many years ago that inadequate choline 
causes the brain to cannibalize its own neural membrane to obtain 
enough choline to make acetylcholine. Because inadequate acetyl-
choline has been associated with memory problems and Alzheimer ’ s 
disease, some researchers have tried to increase the body ’ s choline 
level with various types of medications. 
Many foods contain the essential amino acids. The table 
below shows some of the amino acid precursors, their associated 
neurotransmitters, and a few examples of the foods that contain 
them.
Amino acids can compete with one another for access to the 
brain. The brain ’ s barrier allows only a certain amount of particular 
types of amino acids to pass through at any given time. For example, 
high - protein meals fail to increase the level of L - tryptophan in the 
brain because the other amino acids are more abundant in dietary 
proteins, and these have better access to the brain. This is why eat-
ing a high - protein meal in the evening may make it more diffi cult 
to sleep. To get a good night ’ s sleep, eat a meal high in complex 
carbohydrates and relatively lower in protein so that you can get the 
amount of L - tryptophan you need to sleep well. 
If you want good short - term memory and mental sharpness dur-
ing the day, eat a breakfast or a lunch that is relatively high in 
protein. Consume foods that contain the amino acid that activates 
acetylcholine, norepinephrine, and dopamine.
Vitamins and Minerals 
The foods that you eat must have a balanced spectrum of vitamins 
and minerals. Just like amino acids, vitamins and minerals have a 
direct effect on brain chemistry and the production and/or depletion 
of neurotransmitters. 
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