Food for Life

Food for Life

Food is essential for life, providing the fuel the body needs to function and the building blocks that make up cells, tissues, and organs. The energy provided by food is expressed in terms of calories. The body requires a certain number of calories simply to carry out its basic metabolic functions such as respiration and maintenance of body temperature. Additional calories are needed to support physical activity, fight infection, and rebuild damaged tissues.

If a person does not take in enough calories, fat is broken down to provide fuel. Once the fat is consumed -- or if an individual's metabolism is disrupted due to illness -- lean body mass (muscles and organs) is then used for fuel and raw materials. Conversely, if a person takes in more calories than needed, the extra energy will be stored as fat. The average person needs about 10-20 calories per pound (depending on physical activity level and other factors) to maintain a stable body weight; this requirement is likely to be higher for people with HIV, especially those with advanced disease.

But all food is not equal. While all contain calories, different foods vary widely in the nutrients they provide. A balanced diet is comprised of the following components.

Protein: Protein provides the building blocks of lean body mass. When a protein-rich food is consumed, it is broken down into amino acids, which are reassembled to create enzymes, hormones, and bodily tissues. Most nutrition experts recommend that protein should contribute about 15-20% of the total calories in a person's diet. Good sources include meat, poultry, fish, eggs, dairy products, tofu, nuts, and legumes (e.g., dried beans, lentils).

Carbohydrates: Carbohydrates, which are converted to glucose in the body, are a primary source of energy. Carbohydrates are classified as simple or complex; complex carbohydrates take more time to break down, and thus provide fuel over a longer period of time. Despite the recent popularity of "low carb" diets, most nutrition experts recommend that carbohydrates -- primarily complex ones -- should make up at least 50% of one's total daily calorie intake. Simple carbohydrates are found in processed sugar, honey, fruit and juice, and lactose (milk sugar). Complex carbohydrates are found in grain products such as bread, pasta, and rice; legumes; and starchy foods such as corn, potatoes, winter squash, and root vegetables.