Try the spicy mustard variety sold in Asian food stores, gourmet shops, or exotic food markets. Dr. Jaya Henry of Oxford Polytechnic Institute in England, discovered that the quantity of hot mustard generally used in Indian, Mexican, and Asian recipes, which is roughly one teaspoon, temporarily boosts the metabolism, in a similar way as caffeine and the ephedrine drug do.
However, according to Dr. Henry, mustard is natural, totally safe and is effective. He also adds that it can be used daily. He discovered that mustard can accelerate the metabolism by as practically 20 to 25 percent for several hours.
Peppers are also a rich source of vitamins A and C, abundant in calcium, iron and magnesium, phosphorus, fat-free, high in fiber, low in sodium and contain just 24 calories per cupful.