By Steve Blechman

A new study on branched-chain amino acids (BCAAs) published May 8th, 2022, in the journal Aging Cell reported that “specific composition of dietary protein may be a previously unappreciated driver of metabolic dysfunction and that bcaa restricted diets may be a promising new approach to delay or prevent diseases of aging.”

The report says that “over 50 years ago, it was discovered the plasma levels of BCAAs are positively correlated with insulin resistance and obesity in humans. This has been expanded upon in recent studies of obese and insulin resistant humans around the world.” Insulin resistance occurs when the body becomes resistant to the hormone insulin. According to the Mayo Clinic, “Glucose can’t enter the cells as easily, so it builds up in the blood. This can eventually lead to type 2 diabetes.” High BCAA levels in the blood are present in diabetics. Also “more recently, elevated BCAAs have been associated with negative cardiovascular outcomes.”

This new report says that the catabolite of valine, 3-hydroxyisobutyrate (3-H1B), can enhance fat accumulation in skeletal muscle. 3-H1B can create fatty muscles – a contributor to insulin resistance. Also “elevated BCAAs are specifically associated to poor health outcomes in humans overall, and higher blood levels of isoleucine are associated with increased mortality” and “higher dietary levels of isoleucine are associated with body mass index” and obesity.

The report says that “there are many factors that need to be considered in the application of experimental diets to human patients, mainly safety and feasibility. BCAA restricted diets could conceptually be used as a weight loss and insulin-sensitizing intervention or promote healthy longevity,” and that “feeding and isoleucine restricted diet and testing the effects on longevity is the logical next step.”

A new study published February 19th 2022 in the journal Diabetes, Metabolic Syndrome and Obesity reported that the BCAA valine is strongly linked and correlated to insulin resistance and diabetes. The study involved a Chinese population of 816 individuals. The conclusion of the study found that “L-valine is an independent risk factor of oxidative stress and that high valine levels with oxidative stress could be a significant risk factor for increased type 2 diabetes.”

It has been implicated that the branched-chain amino acids isoleucine and valine, but not leucine, are positively associated with increase of insulin resistance, diabetes and obesity in animals as well as humans. Over 70% of Americans are overweight. Medical researchers have projected that by 2030, one in two adults will be obese. A major health concern!

It was reported May 13^th, 2022 by MedicalXpress that “A new study from Pennington Biomedical Research Center, published in the journal Nature Communications found that reducing the amount of protein in the diet produced an array of favorable health outcomes including an extension of lifespan, and that these effects depend on a liver-derived metabolic hormone called fibroblast growth factor 21 (FGF-21).”

This study goes on to say that “it has long been known that the reducing the amount you eat improves health and extends lifespan, and that there has been increasing interest in the possibility that reducing protein or amino acid intake contributes to this beneficial effect.”

“This groundbreaking research has implications for extending the health and lifespan of people. If scientists can better understand how diets and nutritional hormones like FGF-21 act to extend lifespan, these discoveries could offset many of the health issues that occur in the middle age and later,” said Pennington Biomedical Executive Director John Kerwin, Ph.D.

The new study published May 8th 2022, in the journal Aging Cell says that isoleucine restriction in the diet strongly raised FGF-21! “The molecular mechanism by which FGF-21 levels are increased by isoleucine restriction, and the molecular processes by which dietary isoleucine restriction promotes glucose tolerance and reduces adiposity, remains to be determined.”

This new breakthrough research is essential for the metabolic benefits and lifespan extension of protein or isoleucine restriction. In conclusion, research has shown that limiting BCAAs valine and isoleucine, but not leucine, in the diet may delay aging and promote healthy longevity.

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