As a personal trainer, one of the most common questions I get asked is “how many calories should I eat?” The answer to this question is not a one-size-fits-all as it depends on several factors such as age, weight, height, activity level and overall health. However, there are formulas that can give you an estimate of your daily calorie needs.
In this blog, I will be talking about the Harris-Benedict equation. The Harris-Benedict equation is one of many that is a wildly used formula to calculate an individual’s basal metabolic rate (BMR), which is the number of calories needed to maintain basic body functions such as breathing and digestion. The BMR can be estimated using the following formula:
For men: BMR = 66 + (13.7 x weight in kg) + (5 x height in cm) – (6.8 x age in years)
For women: BMR = 655 + (9.6 x weight in kg) + (1.8 x height in cm) – (4.7 x age in years)
Once you have your BMR, you can estimate your daily calorie needs by taking into account your physical activity level. If you have a sedentary lifestyle, multiply your BMR by 1.2. If you have a light activity level, multiply your BMR by 1.375. If you have a moderate activity level, multiply your BMR by 1.55. If you have a very active lifestyle, multiply your BMR by 1.725.
It’s important to note that these formulas are just estimates and offer you a baseline for your BMR and, subsequently, Total Caloric Expenditure. Unless you use a more advanced scientific devices and protocol for calculating these figures, a baseline is the best way to start. It is also very important not to take your calorie intake below your calculations for your BMR and if needed consult a doctor or a registered dietitian for personalized recommendations. A medical professional May prescribe diets that are below BMR, to fat loss patients; but this is not a safe method and should only be done with under a medical professional care.
Additionally, your calorie needs may change over time as your weight, height, and activity level change, so it’s important to periodically re-evaluate your calorie needs, but note that there are also differences in true value for your daily caloric intake need based on your activity from one day to the next.
It’s also important to note that simply counting calories isn’t enough to ensure a healthy diet. You also need to consider the quality of the food you’re eating. Focus on consuming whole, nutrient-dense foods like fruits, vegetables, lean proteins, and healthy fats. Avoid processed and junk foods, which are high in calories but low in nutrients.
Remember that weight loss and weight maintenance is a marathon, not a sprint. Rapid weight loss is often not sustainable and can lead to yo-yo dieting. Instead, focus on making small, gradual changes to your diet and exercise habits that you can stick to for the long term. This will help you reach and maintain your goals in a healthy and sustainable way.
In addition to counting calories, it’s also important to pay attention to portion sizes. Even healthy foods can lead to weight gain if you eat too much of them. Use a food scale or measuring cups to accurately measure your portions and avoid overeating.
In conclusion, determining how many calories you need per day is an important step in achieving optimal nutrition and maintaining a healthy weight. By using the Harris-Benedict equation and taking into account your physical activity level, you can estimate your daily calorie needs and make informed choices about your diet. There are many ways to get to your daily calorie needs and there will be differences between the results. These formulas are just a baseline for your BMR. There is also the Mifflin-St. Jeor (known simply as the “Mifflin formula”) that gives reflection of the Total Caloric Expenditures. There are also many online calculators available for this and other formulas which will provide quick and accurate results (however, it is beneficial to understand the method/formula that is used to find the resulting figure, not for memorization purposes, but for a personal understanding and benefit of knowledge). As always, it’s best to consult a healthcare professional for personalized recommendations.
REFERENCE:
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). (2021). Calculating Caloric Needs. Retrieved from https://www.niddk.nih.gov/health-information/weight-management/calculating-caloric-needs
- Academy of Nutrition and Dietetics. (2021). Understanding Energy Balance. Retrieved from https://www.eatright.org/health/weight-loss/calories/understanding-energy-balance
- Centers for Disease Control and Prevention (CDC). (2021). Physical Activity for a Healthy Weight. Retrieved from https://www.cdc.gov/healthyweight/physical_activity/index.html
- World Health Organization (WHO). (2021). Diet, Nutrition, and the Prevention of Chronic Diseases. Retrieved from https://www.who.int/nutrition/topics/diet-and-disease/en/
DISCLAIMER:
Nothing contained on this website, regardless of date, should be used as a substitute for direct medical advice from a physician or other qualified clinician.
