Out of the hundreds of messages I get in a day, there is always one question I get far more than any other – “how many calories should I take in and what should my macros be?”. Of course this is without knowing anything about the individual which makes answering that question nearly impossible. But even if it was possible, lets say hypothetically I could determine a perfect calorie and macronutrient ratio for anyone just by knowing their height, weight, etc. is that what really matters? This article is to help provide you with the knowledge to determine starting calorie and macronutrient guidelines but also provide a realization that the start is only half the battle.
Calculators Don’t Work By Themselves
If something is free it’s probably not worth much. This is true with most free online calorie calculators. The fact is no formula is perfect. Yes, there are some that do a decent job of estimating caloric needs based on finding your basal metabolism and then factoring in activity level but at the end of the day its all just guess work. Any diet calculator or formula is just a guess, its not fact and we need to understand that before moving forward. Everyone’s metabolic capacity is not the same despite what could be similar lean body mass and activity level.
The problem is not the calculators, its people that take arbitrary numbers they get from calculators or formulas and believe those numbers (calories / macronutrients) are one hundred percent on point, no questions asked. If you got those numbers by taking your height, weight and multiplying by 10, subtracting by 12, and finished by adding 6…ask yourself how accurate that can possibly be.
Also remember there is no ONE set of calories or macros that is one hundred percent right for you. Like previously mentioned its all a guessing game and you will need to be willing to make adjustments as you progress, and making the right adjustments at the right time is the most important factor in your success. I cant stress this enough.
Now with all that being said I am going to explain how to use these formulas or calculators in your favor. The truth is, if you use numbers generated by these as a starting point you can make them work.
Basal Metabolic Rate (BMR) – Your basal metabolic rate is the total amount of energy (calories) your body requires daily just to maintain normal bodily functions, including digestion, circulation, respiration, temperature regulation, cell construction and every other process in your body. BMR is the total of all the energy you use for basic bodily functions at REST. This does not include physical activity.
Here are a few formulas to help you determine Basal Metabolic Rate (BMR). After you find this out you will need to multiply by an activity factor to determine your maintenance caloric intake.
- Harris Benedict: This is the one you most likely have seen online or in old nutrition text books. By far the most used calorie formula. Despite being fairly complicated, its not very effective, and I wouldn’t recommend it.
MEN: BMR = 66.5 + (13.7 x weight in kg) + (5 x height in cm) – (6.76 x age in years)
WOMEN: BMR = 655 + (9.56 x weight in kg) + (1.8 x height in cm) – (4.68 x age in years)
- Mifflin: Slightly better then the Harris-Benedict but it doesn’t account for body fat/lean body mass so it is limited in how effective it can be. However, if you don’t know your body fat it can be serviceable.
MEN: BMR = (10 x weight in kg) + (6.25 x height in cm) – (5 x age in years) + 5
WOMEN: BMR = (10 x weight in kg) + (6.25 x height in cm) – (5 x age in years) -161
- Owen: Another option which requires a little less calculation. Its simple but I like it for that reason.
MEN: BMR = 879 + 10.2 (weight in kg)
WOMEN: BMR = 795 + 7.2 (weight in kg)
- Katch-McArdle: This one is pretty good if you have a good idea of where your body fat percentage is.
BMR = 370 + (21.6 x LBM) *LBM = (total weight in kg) x (100 – bodyfat %) /100
- Most Basic Formula Possible: This is overly basic but remember we are just looking for an estimated starting point. Obviously there is a lot of limitation to this method. This is for people who like simplicity. This will work A LOT better for the leaner athletic population.
MEN: BMR = (Body Weight in lbs x 8-10)
WOMEN: BMR = (Body Weight in lbs x 7-9)
Activity Factor Multiplier
The activity factor takes into account everything you do in a day not just training. After you find your BMR use one of these multipliers to find the amount of calories you need to stay at the same weight (maintenance calories).
Be honest with yourself here…this is where most people mess this process up.
BMR x 1.2: Sedentary (You don’t move much. No exercise, desk job, lots of TV
BMR x 1.3-1.4: Lightly Active (Active a few days a week, exercise 1-3 days)
BMR x 1.5-1.6: Moderately Active (Where I would assume most people are at. Train 4-5 days a week and active lifestyle)
BMR x 1.7-1.8: Very Active (Training hard for a specific sport or purpose 5-6 hours a week. Typically one with a hard labor job as well)
BMR x 1.9-2.2: Extremely Active (Endurance training or hard charging athlete who spends 10 or more hours training a week and/or lots of activity outside of training. Can require more calories than this as well depending on ones metabolic capacity)
Here is a tool You can use to make this process easier:
*Keep in mind, BMI is a flawed way to determine if someone is overweight. Only use this calculator as rough estimate for BMR.
This is where you need to decide if your goal is to gain or lose weight. As we all know to gain weight you need to be in a caloric surplus and to lose weight you need to be in a deficit. I’m not going to tell you exactly how many calories to add/subtract to gain or lose because it will be different for everyone. What I will say is that in both cases start small and go from there. Take your estimated maintenance calorie intake and adjust that number a little bit and see how you look, feel, and perform, and go from there.
Arguably more important than total calorie intake is the macronutrient breakdown. This could be an entire article itself so I will try and keep this brief. Macronutrients are what make up your calorie intake.
Protein – 4kcal/g
Carbohydrate – 4kcal/g
Fat – 9kcal/g
After you adjust your maintenance calorie intake in order to gain or lose weight depending on your goal, the next step is to figure out your macros. I would start with protein. The age old 1 gram of protein per pound of body weight is pretty accurate.
For this articles sake I am going to recommend the following:
Protein: .8g – 1.2g per pound of body weight
Again this is just an estimate and there could be a need to take this higher or lower. Someone with a high body fat (+ 30%) will not have the required LBM to need a protein intake of .8g per pound of body weight so you will have to go off from a LBM number. On the flip side someone who is on anabolic steroids may benefit from a higher protein intake due to increased protein synthesis rates. Calorie restriction especially low carb/keto dieting also causes protein demand to go up. In either case I don’t see any benefit in going over 1.4 x lb body weight.
After determining protein intake move on to the energy nutrients – Carbohydrates and Fats. These numbers are going to have a WIDE range of possibilities. Like protein, there are essential fatty acids which need to come from the diet. That combined with hormone issues that could come from too low of fat intake, I am going to recommend a minimum fat requirement. After you fulfill the recommended protein and minimum fat intake you are left with the remaining calories to divide up as you like. Personally I like to keep things pretty moderate with a slight shift in favor of carbs and the harder you train the more benefit I see in adding in more carbs. However, I am not trying to spoon feed you MY preferences, you can hire me for that ;)
*Total Calorie Goal – (Protein intake + Minimum Fat Requirement) = Calories left over for carb and fat intake.
Fat: Minimum (.25g) per pound of bodyweight.
This is not necessarily a researched number, just one I find to be effective as a bottom value. Also, I do recommend supplementing with fish oil to make sure you are getting in enough essential fatty acids.
Fish oil is one of the best sources of omega-3 fats which provide a variety of health benefits largely due to decreasing inflammation. Some of the benefits include: healthier blood vessels, a lower lipid count, reduced risk for plaque buildup as well as providing some benefits to a wide range of diseases including cancer, asthma, depression, cardiovascular disease, ADHD, and autoimmune diseases, such as rheumatoid arthritis.
The KEY to Dieting Success – Adjustments Over Time
If this all was as easy as it seems on paper, I probably wouldn’t have a job. The fact is, there actually is A LOT more to the nutrition puzzle then what we went over in this article. A favorite quote of mine is “any idiot can come up with starting calorie and macronutrient targets, a good coach earns their money with the adjustments”.
I ended the introduction by mentioning I wanted this article to provide a realization that the start is only half the battle. The human metabolism is never static. It is constantly changing and your nutrition intake needs to change with it. The real benefit I provide my nutrition clients is being able to look at their progress and make those important adjustments at the right time to avoid plateaus and make sure they reach their goals in a timely fashion.
Any Questions Contact Kyle at:
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