Weight Gain Calculator

Weight Management Explanation

Our bodies require energy for anything we do. Whether that is thinking or moving, we need fuel to initiate and maintain the process of doing work. We get this energy from nutrition in the form of food and drinks, measured in kilocalories (kcal). The kcal we require to maintain our body weight is called the Total Daily Energy Expenditure (TDEE) and reflects how much energy we expend/use in a day. Over time, if we consume more kcal than our TDEE, we gain weight. If we consume less kcal than our TDEE, we lose weight.

Practically all the kcal come from three different groups of food called macronutrients: carbohydrates, protein and fats¹. Each have their essential role to play in maintaining a healthy body and mind. How much you should consume of these macronutrients depends on your lifestyle.

Whether you are interested in losing weight (cutting), gaining weight (bulking) or maintaining a healthy and balanced diet, this tool helps you calculate your macronutrient intake so that you can reach or maintain your desired weight.

¹ Alcohol also provides calories, but is not nutritional. Hence, we leave it out of any further text. Be aware that alcohol provides more calories per gram consumed than carbohydrates and protein.

Diet Types

We have read the science and have selected three lifestyles for which to calculate your macronutrient intake: a balanced diet, a diet for athletes, and one for body builders. Most people will need to select the balanced diet type. Note that, especially in nutrition, research can be divided on some topics. The body is very complex and unique; a schema that works for every human being simply does not exist. Nonetheless, for the diet types we list below, we provide guidelines with numbers that are quite stable across the articles we have read.

All Diets

No matter your diet type, whole, unprocessed and varied food is always healthiest to eat as a base for your nutrition. Of course, eating refined foods from time to time is no issue, especially if you are about to engage in a high intensity exercise. Generally however, the importance of a whole, unprocessed and varied diet cannot be stressed enough.

Balanced Diet

For most people, a healthy diet consists of roughly 50% carbohydrates, 20% protein and 30% fats (Espinosa-Salas & Gonzalez-Arias, 2023; Institue of Medicine, 2005). This means that 50% of the kcal you take in should come from carbohydrates, 20% from protein and 30% from fats. How much that is to grams per day depends partly on your Total Daily Energy Expenditure (TDEE), amongst other factors. The TDEE is the energy in kcal we use in a day. During weight loss, or cutting, we need to eat less kcal than our TDEE. During weight gain, or bulking, we need to eat more than our TDEE.

Athletes

The athlete lifestyle is characterized by intense, long workouts, 5-6 times per week. Because of their intense workout routines, athletes have a very high energy expenditure and thus need to eat a lot to maintain a healthy weight. This means that an athlete's diet requires a relatively higher carbohydrate intake. Carbohydrates are a fast and efficient energy source, which is desired when engaging in high intensity exercise. Note that it is not recommended to go into **a** calorie-deficit when you are an athlete, as it may lead to physical and mental issues (Kerksick et al., 2018). Depending on how intense the athlete works out, the macronutrient balance can be somewhat variable. On average however, a recommended intake consists of 60% carbohydrates, 15% protein and 25% fats.

Body Builders

The body builder is focused on gaining muscle mass and losing body fat. Suffice to say, a body builder's diet consists of an elevated protein intake and a lower fat intake (Roberts et al., 2020; Lambert, Frank & Evans, 2004). Again, the exact numbers vary slightly, depending on gender and intensity of training. Note that, due to higher participation of males in the physical sports, most research has been conducted on male body builders and may be slightly biased. A macronutrient balance we found to be somewhat consistent for body builders is 53% carbohydrates, 30% protein and 17% fats.

Example - how much to eat of each macronutrient per day?

References

• Espinosa-Salas, S., & Gonzalez-Arias, M. (2023). Nutrition: micronutrient intake, imbalances, and interventions. In StatPearls [Internet]. StatPearls Publishing.
• Hall, K. D., Sacks, G., Chandramohan, D., Chow, C. C., Wang, Y. C., Gortmaker, S. L., & Swinburn, B. A. (2011). Quantification of the effect of energy imbalance on bodyweight. The Lancet, 378(9793), 826-837.
• Hall, K. D. (2008). What is the required energy deficit per unit weight loss?. International journal of obesity, 32(3), 573-576.
• Heymsfield, S. B., Thomas, D., Martin, C. K., Redman, L. M., Strauss, B., Bosy-Westphal, A., ... & Nguyen, A. M. (2012). Energy content of weight loss: kinetic features during voluntary caloric restriction. Metabolism, 61(7), 937-943.
• Kerksick, C. M., Wilborn, C. D., Roberts, M. D., Smith-Ryan, A., Kleiner, S. M., Jäger, R., ... & Kreider, R. B. (2018). ISSN exercise & sports nutrition review update: research & recommendations. Journal of the international society of sports nutrition, 15(1), 38.
• Lambert, C. P., Frank, L. L., & Evans, W. J. (2004). Macronutrient considerations for the sport of bodybuilding. Sports Medicine, 34(5), 317-327.
• Roberts, B. M., Helms, E. R., Trexler, E. T., & Fitschen, P. J. (2020). Nutritional recommendations for physique athletes. Journal of human kinetics, 71, 79.
• Standing Committee on the Scientific Evaluation of Dietary Reference Intakes, Subcommittee on Interpretation, Uses of Dietary Reference Intakes, Subcommittee on Upper Reference Levels of Nutrients, Panel on the Definition of Dietary Fiber, & Panel on Macronutrients. (2005). Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids. National Academies Press.
• Wishnofsky, M. (1958). Caloric equivalents of gained or lost weight.