human-energy

How Much Energy Do You Need Per Day?

A person’s daily energy needs consist of the basal metabolic rate and the activity metabolic rate. The basal metabolic rate refers to the amount of energy the body needs at rest to maintain vital functions. The activity metabolic rate includes the energy expended through physical activities.

Factors Influencing Energy Needs

Several factors determine individual energy requirements:

  • Age: Energy needs decrease with age due to a lower basal metabolic rate.
  • Gender: Men generally have higher energy needs than women, which is due to a higher muscle mass.
  • Body weight and size: Larger and heavier individuals require more energy.
  • Physical activity: The more active the lifestyle, the higher the energy expenditure.

Average Guidelines for Daily Energy Needs

The German Nutrition Society (DGE) provides the following average guidelines for daily energy requirements:

Women:

  • 19 to under 25 years: approx. 1,900 kcal/day
  • 25 to under 51 years: approx. 1,900 kcal/day
  • 51 to under 65 years: approx. 1,800 kcal/day
  • 65 years and older: approx. 1,600 kcal/day

Men:

  • 19 to under 25 years: approx. 2,500 kcal/day
  • 25 to under 51 years: approx. 2,400 kcal/day
  • 51 to under 65 years: approx. 2,200 kcal/day
  • 65 years and older: approx. 2,000 kcal/day

These values apply to individuals with primarily sedentary work and a relatively inactive lifestyle. As physical activity increases, energy needs increase accordingly.

Calculating Individual Energy Needs

To determine personal energy needs more precisely, the basal metabolic rate can be multiplied by the so-called PAL value (Physical Activity Level). The PAL value reflects the activity level:

  • 1.2–1.3: exclusively sitting or lying
  • 1.4–1.5: sedentary work with little or no physical activity
  • 1.6–1.7: predominantly sedentary work with occasional physical activity
  • 1.8–1.9: predominantly walking or standing activities
  • 2.0–2.4: physically demanding work or very active leisure activities

Example: A 30-year-old woman with a basal metabolic rate of 1,400 kcal and a PAL value of 1.6 has a daily energy requirement of 2,240 kcal (1,400 kcal × 1.6).

Conclusion

Individual energy requirements vary depending on age, gender, body size, weight, and activity level. It is important to consider these factors to ensure a balanced energy intake.