Bright red berries that look like solid raisins are gaining popularity for their rejuvenating and toning properties. One tablespoon of berries contains one gram of protein, 36% of the daily dose of vitamin A and only 18 calories. Goji berries contain a record-breaking amount of vitamin C (hundreds of times greater than citrus) as well as essential amino acids and polysaccharides. They grow mainly in Asia, Mongolia and Central America.