Why You Can’t Do This On Your Own

Neurotransmitters are a class of chemical messengers in the body that help regulate, either directly or indirectly, most of the other systems and functions in the body. Neurotransmitter imbalances can cause a whole myriad of symptoms in different people, including:

Depression Anxiety Migraines
Insomnia Cravings Increased appetite
Pain tolerance Hot flashes Mood swings
PMS Sleep difficulties Poor memory
Weight gain Poor weight loss Hormone imbalances
Poor mental focus Poor concentration Restless legs
Fibromyalgia Fatigue/Chronic fatigue Thyroid function
Parkinson’s Disease ADD/ADHD Trichotillomania
Addictions Binging behavior Eating disorders
Obsessive thoughts Compulsion Crohn’s disease


Very often, a person can experience multiple signs of imbalance, either at one time or as neurotransmitter imbalance(s) progress. For example, over time a person with severe urges to pull – as with trichotillomania – may also begin to have symptoms of anxiety, poor mental focus and/or sleep disturbances if underlying neurotransmitter balances are not properly addressed and/or get worse. This often leads to a downward spiral of ill-health that seems impossible to get out of.

This is where amino acid therapy can help; by providing the exact blend of nutrients each person needs, properly balanced amino acid therapy can correct almost any underlying neurotransmitter imbalance(s) and restore proper function – which means your symptoms go away. The key is to find the exact right mix of amino acids for each individual person; this is where most people get it wrong, which often leads to further imbalance.

Amino Acid Therapy – Simple in Concept, Complex in Application

The primary neurotransmitter system that needs to be addressed in most people is the serotonin-catecholamine system, which is made up of serotonin (inhibitory) and the catecholamines – dopamine, norepinephrine and epinephrine (excitatory). These neurotransmitters are made from 5-HTP (via L-tryptophan) and L-tyrosine/L-dopa, as illustrated below.


Illustration taken from Marty Hinz, MD – www.hinzmd.com

Often times, once a person realizes that these neurotransmitters can be produced from their respective amino acids, it is very tempting to begin experimenting with different amounts of various amino acids in an attempt to raise or lower neurotransmitter levels in an attempt to achieve proper balance. This is where people (and many health care providers) get into trouble.

Competition Can Create Imbalances

The reason that it is extremely unlikely that a person can stumble upon the exact right blend of amino acids that they need is that both the production (synthesis) and degradation (metabolism) of serotonin and the catecholamines use the same enzymes, which means that they compete against one another. If a person is taking only one precursor, say 5-HTP or L-tryptophan, it will not only raise serotonin levels, it will also cause less dopamine to be made and increase the degradation of dopamine. This has the net effect of creating further neurotransmitter imbalance and/or new imbalances that will lead to additional or more severe symptoms over time.

To illustrate this further, Figure 1 shows how tyrosine is converted into dopamine, norepinephrine and epinephrine and how tryptophan is converted to serotonin. The important thing to see is that the enzyme needed for these conversions is the same (i.e., aromatic amino acid decarboxylase). This means that tyrosine competes with tryptophan (or 5-HTP) to be converted into dopamine or serotonin, respectively. This may not seem like that big of a deal in theory, but in practice it often makes the difference between causing further imbalance and achieving the complete resolution of symptoms.



Figure 1: The synthesis of serotonin, dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline) from amino acid precursors.

Here’s why: because tyrosine and 5-HTP compete with each other for this enzyme taking the improper balance of either amino acid can cause a substantial imbalance in their respective neurotransmitters. Said differently, if you take only 5-HTP or L-tyrosine they will compete with and inhibit the synthesis of the opposite precursor because they compete for this enzyme. This means that if you take only 5-HTP (to increase serotonin) or only L-dopa or L-tyrosine (to increase dopamine levels) you will decrease the synthesis of the other system (dopamine or serotonin respectively).  Over time, this will lead to or increase the neurotransmitter imbalances present, which means more or worse symptoms.

Here is another way to visualize what happens during neurotransmitter synthesis:











Figure 2: Synthesis of serotonin and dopamine in competitive inhibition. Image taken from www.neurosciencemyths.com.

Figure 2 more clearly demonstrates that the same enzyme, aromatic amino acid decarboxylase, is responsible for facilitating the synthesis of both serotonin and dopamine. If one amino acid precursor dominates the enzyme, it leads to decreased synthesis and depletion of the non-dominant neurotransmitter, which means further imbalance.

Once more, even if you take both 5-HTP and L-tyrosine, but they are not in the exact balance your body requires, you will still cause further neurotransmitter dysfunction over time due to this competition for enzymes.

A very similar process applies to the degradation (metabolism) of serotonin and the catecholamines. Figure 3 depicts that the same enzymes facilitate the degradation of both serotonin and the catecholamines; in this instance, the enzymes are called monoamine oxidase (MAO) and catechol-O-methyl transferase (COMT). What this means is that a significant increase in levels of one neurotransmitter will increase the activity of MAO and COMT enzymes. This leads to increased metabolism and depletion of the non-dominant neurotransmitter, which again promotes further imbalance.











Figure 3: Metabolism of serotonin and dopamine in competitive inhibition. Image taken from www.neurosciencemyths.com.

Complex Interactions

In addition, there are many interactions noted in the peer-reviewed literature between amino-acids and neurotransmitters. Figure 4 summarizes these interactions and shows that the determination of the correct balance needed by any given person can be very complex.


Figure 4: Summary of interactions between neurotransmitters and amino acid precursors noted in peer-reviewed literature. Illustration taken from Marty Hinz, MD – www.hinzmd.com

One look at this figure and you can easily see that even though 5-HTP and L-tyrosine are made into serotonin and dopamine, respectively, they also have a number of other effects. Because of this, the odds of a person guessing the correct blend of amino acids necessary to address their specific issues are virtually zero.

Getting the Help You Need

This is why it is so important to work with a health care professional that is trained in the proper use of amino acid therapy: you have to take properly balanced amino acids when you are attempting to improve neurotransmitter function. If you take only one amino acid precursor, the administered amino acid will dominate the enzymes for both synthesis and metabolism of neurotransmitters and compromise proper production of the other system’s neurotransmitters, creating further imbalance, which can lead to more and greater symptoms. The same is true if you take an improperly balanced amino acid formula.

All these complex interactions can make it seem nearly impossible to achieve proper neurotransmitter function. Just as a car mechanic can quickly and efficiently determine how to repair a car’s engine using the right tools and training, so can we help you determine how to restore proper neurotransmitter function. We have the tools, training and experience to make sense of these complex interactions and have helped thousands of people worldwide eliminate their symptoms by achieving proper neurotransmitter function.