Nutrition Sources

Last updated: April 1, 2026

Alimenta uses established, peer-reviewed scientific formulas and guidelines to generate personalized daily nutrition targets. These recommendations are intended as general guidance and should not replace advice from a qualified healthcare professional.

Basal Metabolic Rate (BMR)

Daily calorie targets begin with a Basal Metabolic Rate estimate calculated using the Mifflin-St Jeor equation, one of the most widely validated predictive equations for resting energy expenditure:

• Male: (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
• Female: (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161

Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. “A new predictive equation for resting energy expenditure in healthy individuals.” The American Journal of Clinical Nutrition, 1990;51(2):241–247. doi:10.1093/ajcn/51.2.241

Activity Multipliers

BMR is adjusted for physical activity level using standard activity factors derived from the work of Harris, Benedict, and subsequent refinements:

• Sedentary (little or no exercise): BMR × 1.2
• Lightly active (light exercise 1–2 days/week): BMR × 1.375
• Moderately active (moderate exercise 3–5 days/week): BMR × 1.55
• Very active (hard exercise 6–7 days/week): BMR × 1.725

Goal-Based Calorie Adjustments

Total Daily Energy Expenditure (TDEE) is then adjusted based on the user’s selected goal, following widely accepted sports nutrition principles:

• Fat loss: TDEE − 500 kcal/day (approximately 1 lb/week)
• Maintenance: no adjustment
• Muscle gain: TDEE + 300 kcal/day

These adjustments align with guidelines from the International Society of Sports Nutrition (ISSN) and the American College of Sports Medicine (ACSM).

Macronutrient Distribution

Protein, carbohydrate, and fat targets are set as percentages of total calories, informed by position stands from the International Society of Sports Nutrition:

• Fat loss: 40% protein, 30% carbohydrate, 30% fat
• Maintenance: 30% protein, 40% carbohydrate, 30% fat
• Muscle gain: 35% protein, 40% carbohydrate, 25% fat

Jäger R, Kerksick CM, Campbell BI, et al. “International Society of Sports Nutrition Position Stand: protein and exercise.” Journal of the International Society of Sports Nutrition, 2017;14:20. doi:10.1186/s12970-017-0177-8

Fiber Recommendations

Daily fiber targets of 25–30 grams are based on the Dietary Guidelines for Americans, published jointly by the U.S. Department of Agriculture (USDA) and the U.S. Department of Health and Human Services (HHS).

U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020–2025. 9th Edition. dietaryguidelines.gov

Calorie Conversion Factors

When calculating calories from macronutrients, Alimenta uses the standard Atwater general factors:

• Protein: 4 kcal per gram
• Carbohydrate: 4 kcal per gram
• Fat: 9 kcal per gram

Merrill AL, Watt BK. “Energy Value of Foods: Basis and Derivation.” Agriculture Handbook No. 74, USDA, 1973.

Important Disclaimer

Alimenta provides general nutritional guidance based on established scientific formulas. Individual nutritional needs vary based on medical conditions, medications, and other factors not captured by these calculations. The recommendations provided by Alimenta are not medical advice. Consult a registered dietitian, physician, or other qualified healthcare professional before making significant changes to your diet, especially if you have any health conditions.