Basic Nutritional Science

1. Macronutrients

Macronutrients are the essential nutrients that provide the body with energy and are required in large amounts. They are categorized into three main types: carbohydrates, proteins, and fats.

Carbohydrates

Carbohydrates are the body's primary source of energy. They are broken down into glucose, which is used by cells for energy. There are two types of carbohydrates: simple and complex. Simple carbohydrates, like those found in fruits and sugars, are quickly absorbed by the body. Complex carbohydrates, such as those in whole grains and vegetables, provide sustained energy and are rich in fiber.

Example: A slice of whole-grain bread contains complex carbohydrates that provide long-lasting energy, while a candy bar contains simple carbohydrates that provide a quick burst of energy.

Proteins

Proteins are essential for building and repairing tissues, making enzymes, and supporting immune function. They are made up of amino acids, some of which the body cannot produce on its own and must be obtained through diet. Animal sources like meat and dairy, as well as plant sources like beans and nuts, are rich in protein.

Example: Chicken breast is a high-quality protein source that helps in muscle repair and growth, while lentils provide plant-based protein that supports overall health.

Fats

Fats are crucial for energy storage, insulation, and protecting organs. They are also necessary for the absorption of fat-soluble vitamins (A, D, E, and K). Fats are classified into saturated, unsaturated, and trans fats. Unsaturated fats, found in olive oil and avocados, are generally healthier than saturated fats, which are found in butter and red meat.

Example: Olive oil is rich in unsaturated fats that support heart health, while a cheeseburger contains saturated fats that should be consumed in moderation.

2. Micronutrients

Micronutrients are essential nutrients required by the body in smaller amounts. They include vitamins and minerals, which play critical roles in various bodily functions such as metabolism, immunity, and bone health.

Vitamins

Vitamins are organic compounds that the body needs for growth, metabolism, and overall health. They are divided into two categories: fat-soluble and water-soluble. Fat-soluble vitamins (A, D, E, and K) are stored in the body's fatty tissues, while water-soluble vitamins (B and C) are not stored and need to be replenished regularly.

Example: Vitamin C, found in oranges and strawberries, is crucial for immune function and skin health, while Vitamin D, obtained from sunlight and fortified foods, supports bone health.

Minerals

Minerals are inorganic elements that are essential for various bodily functions, including bone formation, fluid balance, and nerve function. Major minerals include calcium, potassium, and magnesium, while trace minerals like iron and zinc are needed in smaller quantities.

Example: Calcium, abundant in dairy products and leafy greens, is vital for strong bones and teeth, while iron, found in red meat and spinach, is essential for blood health and oxygen transport.