Thursday 31 October 2013

Week 44 Nutrition Tip: Should You Count Calories?

"How many calories should I eat?" I chuckle inside every time I hear that question because 99% of the time it is asked by someone who should not be asking that question. I always want to respond to this question with one of the following questions: "What did you eat for breakfast this morning?" "How many calories are you currently eating?" Or are you willing to daily weigh and measure your food and consistently count your calories?" For the average person, calorie counting is not necessary - they are not at that level and they need to be focused on the basics. However, if you reading this, then chances are good that you are not training and eating to be an average person. As we near the end of this 52 Weeks to Better Nutrition and a New You series, let's look at calories. Is it true that a calorie is a calorie? And, should you be worried about counting them?

"A Calorie is a Calorie!"???
During my master's degree, I remember having an online discussion in our sports nutrition class. One my fellow students wrote, "a calorie is a calorie." Is that true? Well, it guess it depends on the context. Scientifically, this is true. If you measure calories in a food incinerator, then 100 calories of a donut (I guess that is about one bite) or 100 calories from broccoli are the same thing. However, in the human body it is not that simple. Different foods respond differently in the body and thus the outcome of 100 calories worth of food in the form of a donut will differ from a 100 calories in the form of broccoli. Here is an updated version of how I responded to my fellow classmate's statement of "a calorie is a calorie". 

Thermic effect of food
One aspect that contributes to about %10 of the total number of calories you burn each day is the digestion of food (yes, eating and digesting food burns calories). Different foods require a different amount calories to digest. For example, protein often require about double the amount of calories to digest as does fat or carbs. Therefore, even if you eat the same number of calories, by switching to less carbs and more protein you will burn a few more calories. (Note: while this is factor in the over-all calorie equation, it is a relatively small one, so do not get too excited about it).

Different foods also cause a different hormonal response in the body. Eating refined foods causes a greater increase in insulin which (from a body composition perspective) tells the body to store fat. This is not just a theory. Many studies comparing high carb to low carb diets show that even though calories are the same (and in some cases the low-carb subjects even ate more calories) fat loss is greater with a low-carb diet. So much for the calorie is a calorie in the human body.

Chronic low-grade acidosis
Back in week 3 of this series I wrote about the effects of this. Basically, when you eat a diet low in alkaline foods (i.e. fruits and vegetables), your body makes adjustments to regulate pH. The result of these adjustments is it slows down your thyroid and thus decreases metabolism. As a result, you burn less calories each day. Click HERE for more information on chronic low-grade acidosis.

Digestion speed
Refined foods digest quicker. This not only spikes your insulin levels more, it also leave you hungry again soon afterwards and thus you end up eating more. If you have eaten at a Chinese food restaurant (in North America), then you know what I am talking about.

Satiety rating
Some foods make you feel fuller than others. As a result, if you eat foods that do not fill you up as much, you will tend to over-eat and thus end up consuming more calories.

In North America, we have people who are both obese and deficient and key nutrients. When you eat a diet high in processed foods, your body will miss out on many important nutrients. As a result it crave more food to try to get what it is missing.

Another important consideration is context. For people who are overweight, a simple reduction in calories will make them less overweight. Often this will still happen even if food selection is not that great (though fat loss would be even better if food selection was addressed). An extreme example of this is nutrition professor Mark Haub's twinkie diet experiment. However, if you are looking to go from average body composition to athletic lean that is a whole different ball game.

Calorie Counting Considerations
Should I count calories?
If you are currently at or actively moving towards a good body composition, then do not bother counting calories. However, if you are consistently applying sound nutritional principles, training hard (and smart), yet are still struggling to gain lean muscle or lose body fat, then calorie counting may help (see the practical application section below for more details and an alternative).

How many calories should I eat?
The most accurate practical method of assessing caloric need is to weigh yourself and assess your body composition and then simply count calories for a week or two. At the end of this time, re-test your weight and body composition and calculate your daily average calories. If you maintained, then your average is likely your maintenance level. If your goal is to maintain, then stay at that average calorie level. If your goal is to gain or lose, then you will likely need to bring these levels up or down by about 300-500 calories per day.

If you want to get a general starting point, you can also crunch some numbers:

There are many equations that can be used. Here is an example with the  Harris-Benedict equation. To start, you calculate your resting metabolic rate (RMR):
Women: RMR = 655.1 + (9.56 x body weight in kg) + (1.85 x height in cm) – (4.68 x age)
Men: RMR = 66.47 + (13.75 x body weight in kg) + (5.0 x height in cm) – (6.76 x age)
Once you have have calculated your estimated RMR, you can estimate your total energy expenditure by multiplying your RMR by your physical activity factor:
RMR x Physical Activity Factor = estimated daily caloric needs
Sedentary 1.39
Low active 1.49
Active 1.75
Very active 2.06
Note: Always consider individual differences. Some people will need more or less than what these calculations show. If you are way above or below these numbers, avoid making drastic changes to your daily caloric intake, but rather make small, simple changes. Also, for many people training (and sport involvement) will fluctuate throughout the year and as a result, calorie levels and carb intake should change accordingly. For more information on this, check out Nutrition Periodization.

Problems with calorie counting
Calorie counting has a number of problems. For one, it is time-consuming to weigh and measure every single thing that goes in your mouth. Also, as nutrition expert Ryan Andrews of Precision Nutrition points out, calories counting and as well as energy burning calculation can both be off by up to 25%. This leaves a lot of room for error.

Another problem with counting calories is the temptation to play the numbers game. This can result in people eating less good, healthy food to make calorie room for their favorite tasty treats.

Practical Application
Yes, how much you eat matters, but so does what you eat. If you have been following this series and are making good food choices, yet still not moving towards your goals, then you need to start keeping better track of the amounts of what you are eating. A great way to do this is to regularly keep a food journal (click HERE for more details). You will also benefit from monitoring your weight and body composition on a biweekly basis. Then, you can make adjustments accordingly. If you are tracking calories, then you can look to increase calories by about 300-500 if you are trying to gain weight and it is not happening and decrease calories by about the same amount if you are trying to lose fat and it is not happening. An alternative to calorie counting is to simply make small adjustments in what you eat and portion sizes. For example, if you typically have 2 eggs and two pieces of toast for breakfast, you could simply adjust this meal. For fat loss, you could replace the toast with an apple. For muscle gain, you could add the apple and increase the number of eggs. Then, apply this same idea to the other meals. Bottom line: once you are making good and appropriate food choices for your goals, keep adjusting and monitoring your body composition until you find what works for you!

Antonio, J, et al (eds.). Essentials of Sports Nutrition and Supplements. Totowa, NJ: Humana Press; 2008.

Below are the links to the other weekly habits in this series:

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