Amino Acid Therapy

The two most common underlying causes of eating disorders, fatigue and depression include neurotransmitter dysfunction and HPA axis (hypothalamic-pituitary-adrenal axis) dysfunction. Neurotransmitter dysfunction leads to obsessive compulsive actions, forcing people into a downward spiral of food restriction and depression.” Neurotransmitters are brain pathways that talk to each other to influence learning, memory, focus, anxiety, emotions and your state of mind. They are very simply your thinking about yourself, your surroundings and how easy it is to learn and retain information. The two main neurotransmitters that affect our mood are well known are called serotonin and dopamine. Think of them as the master neurotransmitters. They control nearly all the other 180 neurotransmitters in the brain. When deficiencies of serotonin or dopamine are present, all the other neurotransmitters in the brain become unbalanced.

Nutritional deficiencies, neurotoxicity, head injury, and genetics can all cause serotonin and dopamine deficiencies. Their metabolism, synthesis, and uptake pathways are intertwined, so that damage to one affects the other.

That said, their bioavailability is different, in that Serotonin is made available by the amino acids tryptophan and 5-Hydroxytryptophan (5-HTP), whereas dopamine is synthesized from the amino acids tyrosine and L-Dopa. When one of these neurotransmitter precursors is out of balance, however, the metabolism, synthesis, and uptake of either neurotransmitter can be impaired, resulting in disturbances in mood and cognitive functioning. Serotonin and dopamine also regulate things such as appetite, libido, and the circulatory system.

The most logical method to restore serotonin and dopamine would be to take them in a pill form. Unfortunately, this would not be effective since serotonin and dopamine are unable to pass through the Blood-Brain barrier (BBB), so the medication would never enter the brain. The pharmaceutical solution has been to create an SSRI (Serotonin Reuptake) antidepressant. SSRI’s work at the cellular level in the brain by blocking the re-uptake of serotonin after it is released from a cell.

Normally, the brain cell releases a small amount of serotonin which does its job by stimulating another cell to release an electrical charge. Once it’s job is done, it is reabsorbed into the original cell. For the individual taking an SSRI, the medication block’s the reuptake of serotonin so that it remains outside of the cell. The result is that it has more time to do its job.

Two things happen when the serotonin remains outside of the cell: first it continues to hit the neighboring brain cell repeatedly, causing it to fire, which is what makes the individual feel better. Secondly, enzymes within the brain eventually break down the serotonin. Over time this break down results in the additional depletion of the serotonin.

At some point, the brain is too depleted of serotonin for the SSRI drugs to work and the individual must turn to the class of drugs that affect dopamine, one of which are atypical antipsychotics. Unfortunately, long-term use of these drugs eventually results in a dopamine deficiency. In addition to which, atypical antipsychotics have significant side effects including weight gain, type II diabetes mellitus, hyperlipidemia, myocarditis, sexual dysfunction, extrapyramidal side effects and cataracts.

There are two main amino acids that can pass through the BBB, 5-HTP and tyrosine; 5-HTP affects serotonin, while tyrosine affects dopamine. When the correct ratio of 5-HTP and tyrosine and several other co-factors are taken (usually cysteine, calcium, vitamin C, and vitamin B6) the brain can generate the appropriate amount of serotonin and dopamine. It is critical that 5-HTP and tyrosine are taken together. If either are used on their own, the opposite neurotransmitter will eventually be depleted; taking 5-HTP on its own would result in a dopamine deficiency, taking tyrosine on its own would result in a serotonin deficiency. Also, if there isn’t enough of each of the co-factors available in the brain (most importantly vitamin B6), 5-HTP will not convert to serotonin and tyrosine will not convert to dopamine.

As amino acid therapy progresses, the brain begins to heal and repair itself; there is an increase in neurotransmitters. Neurotransmitters also begin to operate at a normal level forcing a growth of new connections. Oftentimes, the individual can eventually stop taking the 5-HTP and tyrosine and continue to experience the benefits they received while utilizing amino acid therapy.

Typically, lab tests are required to determine the correct dosage of 5-HTP and tyrosine, since the ideal dose will vary from person to person. An example starting dose is usually 1000 mg of tyrosine (3 times per day, maximum dose of 3000 mg per day) and 100 mg of 5-HTP (3 times per day, maximum dose of 300 mg per day).

Good nutrition is always recommended along with targeted supplementation as it supports a healthy digestive system, detoxification and supplies the necessary co factors that help to precursor amino acid synthesis into neurotransmitters.

Vitamin C is a co-factor for the conversion of 5-HTP to Serotonin, it also prevents 5-HTP from being diverted to other pathways. It is also a required nutrient in the conversion of dopamine to norepinephrine.

Folic Acid in an activated form is essential for a healthy nervous system and low levels are common with depression and dementia.

Vitamin B6 as Pyridoxyl 5′ Phosphate (P5P) is the active co enzymatic form of B6 and involved in both amino acid and fatty acid metabolism, and in the production of key neurotransmitters and serotonin and other key neurotransmitters.

B12 is required for neurological health and fatty acid metabolism and deficiency presents in anaemia, depression and poor concentration.

Amino Acids along with diet are usually well tolerated and an effective alternative to prescription antidepressants for many patients. They have a short life and do not need to be loaded on and off, but are effective after consumption and taken as often as needed with little to no side effects.


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