2023-10-13 00:30:02
New studies added to FAQs
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We added a bit more information to our FAQs on this page, largely related to isoleucine's relationship with glucose control.
Isoleucine
•Last Updated: October 13, 2023
Isoleucine is one of the three branched-chain amino acids (BCAAs). It is an essential amino acid. Isoleucine is required for muscle protein synthesis, and it may help to reduce post-exercise muscle soreness and markers of muscle damage when taken as part of a BCAA supplement. However, whether isoleucine holds any special merit as a supplement on its own is unclear.
Isoleucine is most often used for
Last Updated:October 13, 2023
Isoleucine is an essential branched-chain amino acid that must be consumed regularly and is found in dietary proteins such as meat, fish, soy, and dairy. It serves as a building block for proteins and plays a role in regulating protein, glucose, and lipid metabolism, as well as immune function.
Isoleucine is essential for muscle growth and protein synthesis, and it may aid in muscle recovery (when it is included in branched-chain amino acids supplements) by reducing soreness and muscle damage. However, its effectiveness in enhancing performance or providing additional benefits when it is taken alone at doses above the Recommended Dietary Allowance remains unclear.
Isoleucine is generally well tolerated, but some individuals may experience gastrointestinal issues like nausea and diarrhea, particularly if it is taken as part of a branched-chain amino acids (BCAAs) supplement. Additionally, higher blood levels of isoleucine have been associated with health conditions such as insulin resistance, type 2 diabetes, cardiovascular disease, and obesity, though further research is needed to clarify the relationship.
Isoleucine is an amino acid that is essential for protein synthesis, muscle growth, and recovery. It may also lower blood glucose levels by improving glucose uptake in skeletal muscle, increasing glucose breakdown for energy, and decreasing glucose production in the liver.
The recommended daily allowance (RDA) of isoleucine established by the Institute of Medicine is 19 mg of isoleucine per kilogram of bodyweight (mg/kg) daily. This is the average amount of isoleucine that meets the nutritional requirements of most people.[1]
Isoleucine can be supplemented individually, but it is more commonly taken as part of a BCAA or complete protein supplement (e.g., whey protein, soy protein). There is currently no strong evidence to support the use of isoleucine as a supplement alone and no well-established dosing.
In rat studies, dosages of 0.3–0.45 mg/kg were effective for reducing blood glucose and increasing muscle cell glucose uptake.[2][3] This could be extrapolated to a human dose of 48–72 mg/kg (for a 150 lb person, 3.3–4.9 g), but these beneficial effects have not yet been clearly established in clinical trials.
2023-09-12 17:02:58
Standard FAQ and database update
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We searched for new studies on isoleucine, analyzed them, and added their information to our FAQs and database.
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