In the “Big Leap,” psychologist Gay Hendricks calls it the “upper-limit problem.” “Millions of people are stuck on the verge of reaching their goals, can’t seem to scale the wall ...

Recommended level for eye health: 10 mg/day for lutein and 2 mg/day for zeaxanthin. Safe upper limit: Researchers have not set an upper limit for either. Potential risks: In excess, they may turn ...

It has recently been proposed that the true upper normal limit of serum alanine aminotransferase (ALT) is much lower than that listed by the manufacturers of commercially available assays.