Many companies offer products that seek to support normal brain health. D5’s scientifically researched formula addresses the need for balanced amino acid precursor administration, which is an area that many companies fail to understand or choose to ignore.

Normal brain support requires a balance between the amino acid precursors supporting serotonin and those supporting the catecholamines. It has only been in the last few years that science has come to better understand the conclusions of our early research — without properly balanced nutrients, it is possible to do more harm than good when using amino acid support. The need for balanced amino acid precursor administration is necessary because the enzyme that converts L-dopa into dopamine is the same enzyme that converts 5-HTP into serotonin. D5 is formulated to support this balance. D5 may be selected when a healthcare provider determines that Mucuna support will benefit their patient.

Why does a shared enzyme matter to balanced amino acid administration? The proper ratio and chemistry of balanced administration is more complex than can be covered here. However, a simple explanation is that administering 5-HTP at a higher ratio than recommended will reduce the access that L-dopa has to the shared enzyme. L-dopa will not be able to convert into dopamine as it should be able to do. The same is true if you administer Tyrosine or L-dopa at a higher ratio than recommended. These precursors will crowd out 5-HTP, reducing its conversion into serotonin. Eventually, the reduced conversion of the outnumbered group will result in the depletion of serotonin or dopamine, depending on which precursor is outnumbered. This depletion will have implications throughout the body. This depletion can occur from the administration of only serotonin precursors, only dopamine precursors, or an incorrectly balanced ratio of both serotonin and dopamine precursors. It is possible to do more harm than good by administering incorrectly balanced amino acid precursors

D5’s three key nutrients – 5-HTP, L-tyrosine, and Mucuna Pruriens standardized to 40% L-dopa provide normal support the following neurotransmitters:

Serotonin – associated with control of mood, appetite, sleep, memory, learning, and temperature regulation.

Dopamine, norepinephrine and epinephrine (the catecholamines) – associated with control of movement, balance, motivation, addiction, focus, and the drive for reward.

Serotonin and the catecholamines cannot be directly administered to support normal brain health because they are unable to cross the protective layer around the brain known as the blood brain barrier. Thankfully, serotonin can be supported by 5-HTP. The catecholamines can be supported by L-tyrosine and L-dopa (naturally sourced from Mucuna), which cross the brain’s protective layer and convert into these crucial neurotransmitters.

5-HTP is the most direct way to support serotonin

5-HTP crosses the blood brain barrier
5-HTP is freely converted into serotonin without biochemical feedback inhibition
5-HTP is more efficient at supporting serotonin than tryptophan

For normal serotonin support, 5-HTP is superior to tryptophan because tryptophan hydroxylase, which converts tryptophan into 5-HTP, is limited in terms of enzymatic activity. Once tryptophan hydroxylase reached its threshold, additional tryptophan will not yield more 5-HTP. Therefore, tryptophan does not support serotonin as well as 5-HTP.
5-HTP is found in very trace amounts in a very small number of foods. Therefore, 5-HTP supplementation is the most direct way of administering additional 5-HTP.


L-tyrosine and L-dopa have an important role in providing normal support to the catecholamine system

L-tyrosine and L-dopa cross the brain’s protective layer.
When supplementing with L-dopa, L-tyrosine maintains normal L-dopa levels in the body without fluctuations. L-dopa is the intermediary molecule between L-tyrosine and dopamine. L-tyrosine’s ability to maintain normal L-dopa levels is essential for consistent normal catecholamine levels. Until recently, L-tyrosine’s importance was not well understood, making it an often overlooked nutrient for supporting catecholamine health.
L-dopa (naturally sourced from Mucuna) is more effective at supporting dopamine assuming that adequate levels of L-tyrosine are present. Therefore, many healthcare professionals choose to use L-tyrosine as a supporting base and increase Mucuna levels when they determine that addition dopamine support is needed.

Important: These statements have not been evaluated by the Food and Drug Administration (FDA). These products are not intended to diagnose, treat, cure, mitigate, or prevent any disease.

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