What roles do nutritional deficiency and nutritional excess play in disease?

Nutritional deficiency and nutritional excess can both play a role in the development of various diseases. Nutritional deficiency is defined as an inadequate intake or impaired absorption of essential nutrients needed for health and normal body function (Nelson, 2019). A few common examples of these deficiencies include iron, iodine, zinc, Vitamin D, calcium, and Vitamin B12. On the other hand, nutrient excess occurs when people consume excessive amounts of energy-dense foods such as processed carbohydrates and fats that are high in calories but low in nutrients (Oyebola et al., 2017). Excess consumption from either type of food can lead to weight gain which increases the risk for chronic illnesses such as cardiovascular disease and diabetes.