elissa - Glossary - Page 52 of 57

L-Tyrosine

A conditionally-essential amino acid synthesized from L-phenylalanine.  L-tyrosine is a precursor to the catecholamine neurotransmitters, l-dopa, dopamine, norepinephrine, and epinephrine – which are important contributors to mood and cognitive performance.  It’s also a precursor to the thyroid hormone thyroxine (also known as T4). In larger amounts, L-tyrosine has been shown to improve memory, psychomotor skills and...

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Lutein

A dietary carotenoid that concentrates within the human lens and retina and protects against age-related macular degeneration.  Unlike several other carotenoids, such as alpha and beta-carotene, lutein does not have pro-vitamin A activity.  Spinach and other dark green leafy vegetables are good sources of lutein. See the Linus Pauling Institute Micronutrient Information Center for more...

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L-Norvaline

An analog of the amino acid valine. L-Norvaline is an (in-vitro) inhibitor of the arginase enzyme, which breaks arginine down to ornithine and urea.  Thus, L-norvaline is sometimes added to NO (nitric oxide) supplements as a “nitric oxide amplifier,” on the theory that inhibiting arginine breakdown can will enhance NO...

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Inosine

A component of tRNA (transfer RNA) and is also a precursor to adenosine—a compound vital to energy production (as in ATP—adenosine triphosphate). Inosine was once promoted as a strength/power supplement, but several studies on cyclists and runners have concluded that inosine supplementation does not improve athletic...

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Huperzia serrata

Chinese club moss and source of Huperzine A.  Standardized extracts of Huperzia serrata are often used in pre-workout supplements to enhance focus/concentration.

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Huperzine A

An alkaloid isolated from a Chinese moss (Huperzia serrata) that has neuroprotective and cognitive effects.  Huperzine A is often added to pre-workout supplements to enhance focus/concentration.

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