The body needs a constant supply of food to break it down and produce energy. It is this energy that is the ‘fuel’ for all activity in the body even the life sustaining process when one is asleep. Energy needs often decrease in the senior years as a person becomes less active. Maintaining the same calorie intake in food as when younger may therefore lead to weight gain. However, consuming less calories than is needed can contribute to excessive weight loss, fatigue and other health complications. It is therefore important for the elderly to maintain a calorie intake that meets their needs.
Calories are a unit of measure for energy. Foods that are eaten can be broken down to produce energy and is therefore quantified in calories.Similarly any activity requires energy which is measured in calories. A single calories (cal) is too small a unit to quantify the intake and output of energy and therefore the kilocalorie (kcal) is used. For convenience, however, kilocalories are simply termed as calories when discussing the energy needs in humans.
The calorie needs of a person varies per individual, largely dependent on one’s physical activity. Furthermore the age, gender, height and weight of a person will also determine their daily calorie requirement. The average adult female requires about 1,800 to 2,000 calories per day while the average adult male needs about 2,200 to 2,500 calories per day. Most people depend on their appetite to determine when they need more calories or not. However, this is not always a reliable indicator of one’s calorie requirements in a person with an eating disorder, certain chronic ailments or those using certain medication.
The simplest indicator of a person’s calorie needs is one’s body weight. If a person eats sufficient calories as is needed for daily activity then there no weight loss nor gain and the body weight will be within the normal range. A net gain of calories by eating more than that which is utilized will result in weight gain. A person will be overweight or obese as the excess calories are stored as fat. Conversely, eating less calories than the daily requirement for activity will lead to weight loss. A person will therefore be underweight.
All food groups have calories. Most of the calories should be derived from carbohydrates and the least from fats. The calorie content ounce-per-ounce differs among the various types of food. However, fats have almost three times the amount of calories when compared ounce-for-ounce with carbohydrates. The problem in the elderly is that advancing age alters the appetite and this is further compounded by chronic diseases, poor dentition and the use of certain medication. Overall there is a decrease in appetite and therefore a reduction in calorie intake. Even in the absence of these predisposing factors, economic factors and ignorance about nutrition leading to eating patterns such as the tea and toast diet greatly affects the balance of calories.
Any activity, whether physical or mental, requires energy. This means that calories are consumed. The more strenuous physical activities like running, swimming and sports often utilize the most amount of calories. However, even at rest the body is consuming calories to sustain life processes like breathing and heart contractions. The muscle cells are the biggest consumer of calories, even at rest, mainly due to its larger number of mitochondria (energy producing components) than other types of cells. The elderly utilize less calories in this regard due to a more sedentary lifestyle. It is further compounded in those who are physically disabled, bed ridden or suffering with chronic conditions. Muscle loss in the elderly and other age related changes in the metabolism further reduces the calorie utilization even at rest.
A balanced eating plan and the ability to maintain a healthy body weight are the best approaches to ensuring a suitable calorie intake in the elderly. The body mass index (BMI) which is the ratio of height-to-weight is a simple indicator of whether the body weight is within the normal range. However, just maintaining a normal body weight in the absence of any physical activity is not helpful. Exercise has various health benefits in the elderly. Therefore one’s calorie intake should be sufficient for a person’s lifestyle with a healthy exercise regimen.