http://www.berkeleywellness.com/html/ds/dsArginine.php
the Federal Trade Commission stopped the company from making such unsubstantiated medical claims. (Only drugs are allowed to make explicit medical claims, after stringent testing for safety and efficacy.) Other types of arginine supplements include Herc Vitality Drink Mix and Niteworks. The latter is made by Herbalife, which not only claims that the product is based on Nobel Prize-winning research (several arginine products make this claim), but also boasts that one of the Nobel winners has actually collaborated on its supplement. That doesn’t mean that Niteworks is better than any other arginine supplement. The ads for these products avoid explicit medical claims, but they still make it sound like the products are drugs, not dietary supplements. And they sometimes cost as much as drugs—$90 a month for Niteworks, for instance.---------- In theory, all this is promising, but arginine’s benefits are uncertain and its long-term safety unknown. Briefly boosting nitric oxide may not actually benefit people with cardiovascular disease, let alone those hoping to avoid it. ------------And no one really knows what large doses of this isolated amino acid do in the body over the long haul. Increased amounts of isolated amino acids can create imbalances with other amino acids and thus have adverse effects. ---------Increased nitric oxide might be dangerous for people with certain medical conditions, such as kidney failure or cancer. And no one knows what’s the right dose or when it should be taken.