Rasam contains tamarind that is rich in dietary fibre or non-starch polysaccharides, such as mucilage, pectin, hemicellulose, tannin and gums. It adds bulk to food and eases bowel movement. The black pepper content of rasam is what helps the body lose weight. It promotes removal of toxins by making the body sweat and produce more urine. Thus, the body’s metabolism is kept working properly.