Almost every brand of energy drink now makes a sugar free diet version so sugar content is no longer an issue. Monster is a good one with many good flavors. Rock Star brand.... the one whos logo is "party like a Rock Star" makes a berry flavor that is really good.
Personally I find very little effects of drinking them. I'll drink one on the golf course rather than a beer cause like a gatorade it tends to quench thirst but I find no added energy... But I'm someone who can drink twenty espressos and not bounce off the walls.
I think the crap in the Red Bulls and some others that tastes like shit is the taurine. Its an amino acid found in plants.
http://www.thorne.com/altmedrev/fulltext/taurine3-2.html
Therapeutic Applications of Taurine
by Timothy C. Birdsall, ND
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Abstract
Taurine is a conditionally-essential amino acid which is not utilized in protein synthesis, but rather is found free or in simple peptides. Taurine has been shown to be essential in certain aspects of mammalian development, and in vitro studies in various species have demonstrated that low levels of taurine are associated with various pathological lesions, including cardiomyopathy, retinal degeneration, and growth retardation, especially if deficiency occurs during development. Metabolic actions of taurine include: bile acid conjugation, detoxification, membrane stabilization, osmoregulation, and modulation of cellular calcium levels. Clinically, taurine has been used with varying degrees of success in the treatment of a wide variety of conditions, including: cardiovascular diseases, hypercholesterolemia, epilepsy and other seizure disorders, macular degeneration, Alzheimer's disease, hepatic disorders, alcoholism, and cystic fibrosis. (Alt Med Rev 1998;3(2):128-136)
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Introduction
Taurine (2-aminoethanesulfonic acid, see Figure 1) is a conditionally-essential amino acid which is not utilized in protein synthesis, but rather is found free or in simple peptides. First discovered as a component of ox bile in 1827, it was not until 1975 that the significance of taurine in human nutrition was identified, when it was discovered that formula-fed, pre-term infants were not able to sustain normal plasma or urinary taurine levels.1 Signs of taurine deficiency have also been detected in children on long-term, total parenteral nutrition,2 and in patients with "blind-loop" syndrome.3 In vivo studies in various species have shown taurine to be essential in certain aspects of mammalian development, and have demonstrated that low levels of taurine are associated with various pathological lesions, including cardiomyopathy, retinal degeneration, and growth retardation, especially if deficiency occurs during development.4
Derived from methionine and cysteine metabolism, taurine is known to play an important role in numerous physiological functions. While conjugation of bile acids is perhaps its best-known function, this accounts for only a small proportion of the total body pool of taurine in humans. Other metabolic actions of taurine include: detoxification, membrane stabilization, osmoregulation, and modulation of cellular calcium levels. Clinically, taurine has been used in the treatment of a wide variety of conditions, including: cardiovascular diseases, epilepsy and other seizure disorders, macular degeneration, Alzheimer's disease, hepatic disorders, and cystic fibrosis. An analog of taurine, acamprosate, has been used as a treatment for alcoholism.
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Biochemistry and Metabolism
Although frequently referred to as an amino acid, it should be noted that the taurine molecule contains a sulfonic acid group, rather than the carboxylic acid moiety found in other amino acids. Unlike true amino acids, taurine is not incorporated into proteins, and is one of the most abundant free amino acids in many tissues, including skeletal and cardiac muscle, and the brain.5
In the body, taurine is synthesized from the essential amino acid methionine and its related non-essential amino acid cysteine (see Figure 2). There are three known pathways for the synthesis of taurine from cysteine. All three pathways require pyridoxal-5'-phosphate (P5P), the active coenzyme form of vitamin B6, as a cofactor. A vitamin B6 deficiency has been shown to impair taurine synthesis.6
The activity of cysteine sulfinic acid decarboxylase (CSAD), the enzyme which converts both cysteine sulfinic acid into hypotaurine, and cysteic acid into taurine, is thought to reflect the capacity for taurine synthesis.7 Compared to other mammals, humans have relatively low CSAD activity, and therefore possibly lower capacity for taurine synthesis.8 Much of the published research on taurine has involved studies done on cats, which do not synthesize taurine, but must consume it in their diet.5 Therefore, since humans have the capacity to synthesize at least some taurine, it is unclear to what extent feline studies can be extrapolated to humans.
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