Are all calories made equal?
A calorie is quite literally a unit of measurement, like a centimetre or degree Celsius. In that sense, every single calorie is the same. You’ll be locked in a battle with the calories you consume and the calories you burn for all of time, when our weight is staying pretty much stable we call this Maintenance Calories, when our bodyweight is going up we call this a Calorie Surplus and when our weight is going down we call this a Calorie Deficit.
Weight loss & weight gain mathematically is incredibly simple. Unfortunately in real terms they are quite complicated and also the subject can be very emotional which leads to further poor decision making. BUT make no mistake, if your body weight is consistently not going down, you ARE NOT in a calorie deficit, despite what an app might tell you.
Here are some facts & myths about calories to help you understand the process:
Some calories have a different “Thermic Effect of Food” (TEF). For example a chicken breast might have a 25% thermic effect, this means that if you eat 100 calories (kcal) worth, it will cost 25 kcal for the body to digest it, thus resulting in a net gain of 75 kcal. Vegetables tend to have the highest TEF, shortly followed by Fruit, Lean Meat/Fish & some starchy Carb sources like potatoes and pasta have a decent TEF. Oils and sugars have the lowest possible TEF.
Some calories will produce a greater suppression in hunger. Starchy carb sources and Proteins tend to score really highly in rating for satiety. I’ll caveat that with sometimes something sweet tasting can also really curb hunger pangs.
Rapid changes in bodyweight are more to do with changes in total body water than calories in vs out. If you gained 2 kg (4 lbs) in one weekend, or if you lost 2 kg in one week of dieting, it’s likely at least 50% water weight gain or loss, not genuine fat gain/loss. Here’s why: 0.5kg of body fat is roughy 3500 kcal, so losing 1kg of fat across the week is roughy a deficit of 7700 kcal for the week (or 1100 per day) which is actually a really large deficit. So to gain 2 kg of actual body fat in 2 days you would have to overeat by nearly 15,000 kcal in 2 days, assuming your moving and burning some energy you have to eat nearly 20,000 kcal. Unlikely. So if you’re weight goes up or down rapidly, don’t get too upset (or too ambitious with weight loss targets). Unfortunately we start eating less, we also start eating less carbohydrate (which is stored with water in our muscles and liver), causing body water levels to reduce and body weight to drop quickly.
Our Resting Metabolic Rate (aka our metabolism) is the amount of energy we need for basic survival not including any movement (stuff like heart rate, digestion etc). On the whole, doesn’t change & and can be pretty accurately calculated with a formula. As we age it reduces gradually, and it’s lower when we are lighter. When we diet down, weight loss progress does slow down, this in small part is due to a lower metabolic rate when you get lighter. BUT - it’s more to do with the body trying to achieve homeostasis, unfortunately it wants to hold onto it’s excess energy stored within fat, so it will reduce things like fidgeting, blinking and other subconscious behaviours that reduce your overall calorie intake, thus shrinking the deficit that was originally bigger. The best way to counter this is to be mindful about your movement daily, track your steps, take breaks from sitting down, don’t overdo screen time.
