Ginseng—a popular ingredient in teas and energy drinks—may pack purported powers. In a study at the Mayo Clinic, chronically-fatigued patients who took 2,000 milligrams of ginseng experienced less fatigue than those who didn’t. The effects seemed to last up to eight weeks!

This doesn’t give you the green light to rely on energy drinks for your energy, that’s a whole other story. Discuss with your doc before taking ginseng in its herbal form, because supplements can interact with prescriptions. But who knows, it might give you an edge in feeling younger—and looking more bright-eyed than ever.

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