The Health Impact of Sugar. Sugar may affect our body. Most important function of sugar is to provide energy. The energy of the body gets from food, fruit and beverages. Although, sugar provides energy in term the body. But it has negative effect on the health and excessive amounts of sugar can cause many diseases such as heart disease, diabetes, obesity, and etc. Additionally, those primary diseases may lead to other chronic illnesses like hypertension, cardiovascular disease,etc. Moreover, sugar has effects on the brain. Our natural feel-good brain chemical is the neurotransmitter and serotonin and our bodies naturally make these in balanced amounts and sugar raises the serotonin level in our brain. Therefore, we can understand why we “feel good”eating sweets.However, We should turn to eat natural sugar and to avoid the possibility of the diseases.