Calories In Vs Calories Out

By James Tsitas on 23 February 2021

Calories In Vs Calories Out
 
For weight loss, one thing I preach to my clients is to make sure their calories ingested (food/drink intake) are lower than their calories expended (Basal Metabolic Rate [BMR], Non-exercise Activity Thermogenesis [NEAT], Exercise Activity Thermogenesis [EAT], Thermic Effect of Food [TEF]). 

If their goal is to gain weight, then the opposite applies and calories in should be greater than calories out. This is the nuts and bolts of the weight loss/weight gain conundrum and this calorie balance counts, more than anything else. 

Protein and carbs have different calories per gram (4.0), compared with fats (8.9). But, when total calories are matched people lose weight; despite the macronutrient composition of the diet. This is also true when comparing low sugar diets and sugar containing diets. In the referenced study [1], participants were allocated to either a low-sugar diet (LSD) or a sugar-containing diet (SCD). Each participant was in a calorie deficit of approximately 600 calories per day. There were no statistically significant differences in fat loss at the end of weight loss programme 2.2 kg per person in the LSD vs. 3.0 kg per person in the SCD. 

Markers of inflammation, blood pressure, blood lipids are also similar when comparing high-sugar diets vs. low-sugar diets, when calories and protein are matched [2,3]. So, once again, it is the total caloric and total protein intake that matters for fat loss AND health, not so much the ratio of carbohydrate/fat/sugar makeup in the diet.

You can keep calories ingested, lower than calories out in a variety of different ways. Limit portion sizes, eat less calorie dense foods, diet through low-fat or low-carb diets, juice cleanse and every other fad diet you can think of. However, they all work due to the fundamental principle of lowering the amount of calories you are eating.

However, there are regulatory bodily changes that can make attaining a calorie deficit a bit tricky. Some of these regulatory changes include:

The desire to not move around as much and/or not exercise as intensely (NEAT and EAT are lowered), when dieting. Causing a decrease in calories burned. 

Your hunger levels will also rise in response to weight loss, causing an overriding feeling to refeed.

Your BMR i.e your metabolism, will also lower in response to weight loss, causing you to burn less calories at rest.

These are all things you need to account for when attempting to lose weight and are all things that will effect the calories in vs. calories out equation 

If you’re eating in a caloric deficit and not losing weight, your body may also be retaining water. This can happen due to the stress accompanied by dieting (and exercising), the stress hormone cortisol can build up and cause fluid retention. Additionally, creatine supplementation pulls water into the muscles and can cause scale weight to increase. An increase in carbohydrate intake can also increase fluid retention (not true fat gain, but scale weight will increase). Plus, merely drinking more water per day, can cause the body to retain more water! 

Certain health issues and medications can also affect weight loss, so a solution to this is discuss it with your doctor to see if there are any other options. If there isn’t, then accept that your certain situation may make fat loss a bit harder, and work on the things you can control.

With all that in mind, regular tracking through body composition scans, checking your scale weight, taking progress photos and following some sort of nutrition plan can help you make sure you're kept accountable and can overcome the challenges in manipulating the calories in vs. calories equation for weight loss, weight gain or weight maintenance. 
 
 [1] West, J. A., & De Looy, A. E. (2001). Weight loss in overweight subjects following low-sucrose or sucrose-containing diets. International journal of obesity, 25(8), 1122-1128.
[2] Saris, W. H., Astrup, A., Prentice, A. M., Zunft, H. J., Formiguera, X., Verboeket-van de Venne, W. P. H. G., ... & Vasilaras, T. H. (2000). Randomized controlled trial of changes in dietary carbohydrate/fat ratio and simple vs complex carbohydrates on body weight and blood lipids: the CARMEN study. International Journal of Obesity, 24(10), 1310-1318. 
[3] Surwit, R. S., Feinglos, M. N., McCaskill, C. C., Clay, S. L., Babyak, M. A., Brownlow, B. S., ... & Lin, P. H. (1997). Metabolic and behavioral effects of a high-sucrose diet during weight loss. The American Journal of Clinical Nutrition, 65(4), 908-915.