Negative Caloric Balance (Caloric Deficit)

If energy expenditure exceeds caloric intake, a person is in negative caloric balance and a caloric deficit exists. The example given is a person who consumes 2,500 kcal per day while expending 3,000 kcal per day. The resulting 500-kcal caloric deficit leads to weight loss as the body primarily uses stored adipose tissue to meet its daily energy needs.

A negative caloric balance can be attained three ways: by decreasing caloric intake, by increasing energy expenditure through exercise, or by combining a decrease in caloric intake with increased participation in regular physical activity. A combination of restricted caloric intake and exercise is the recommended approach.

The source emphasizes as a KEY POINT that a negative caloric balance of 3,500 kcal is required to lose 1 lb of adipose tissue, and that the deficit is best achieved through a combination of caloric restriction and increased physical activity.

• Negative caloric balance: expenditure > intake.
• Worked example: 2,500 kcal in − 3,000 kcal out = −500 kcal/day deficit → weight loss.
• The body primarily uses stored adipose tissue to make up the deficit.
• 3,500-kcal negative balance = 1 lb of adipose tissue lost.
• Best achieved by combining caloric restriction with increased activity.

• caloric-balance — the parent concept.
• positive-caloric-balance — the opposite state.
• adipose-tissue-rule — the 3,500 kcal = 1 lb rule.
• safe-deficit-rate — limits on how large a daily deficit should be.