Camu camu

Camu camu is a small, tart berry from the Amazon rainforest, and it's one of the richest known food sources of vitamin C. You'll usually find it as a freeze-dried powder, since the fresh fruit is very sour and doesn't travel well. Vitamin C is an antioxidant that supports normal immune function and helps your body absorb iron from plant foods.

A little goes a long way:

• Start with 1/4 to 1/2 teaspoon in a smoothie, yogurt or a glass of water
• Add it after cooking, since heat breaks down vitamin C
• Store it airtight, away from light and moisture

Because it's so concentrated, check with your doctor or practitioner if you take medications or other supplements. Try this: stir a pinch into your morning smoothie and enjoy the bright, citrusy tang.