From espresso to energy drinks to supplements, caffeine comes in many forms, Rula notes. And if you're like most people, you probably enjoy a cup of coffee each morning or a late-afternoon soda to ...

Caffeine helped yeast cells live longer, especially under stress. The benefits depend on specific internal proteins and pathways. In some cases, caffeine made DNA damage worse by disrupting repair.

Whether you drink it for the taste or the energy boost, it's hard to resist a smooth cup of coffee. However, it can often leave you feeling jittery and craving more once the initial boost wears off.

We love a quick fix and a new swath of coffee-inspired diets is making the rounds — or grounds, as it were — promising a lean ...