Is Losing Weight Really as Simple as ‘Calories in vs. Calories Out’?

Is Losing Weight Really as Simple as 'Calories in vs. Calories Out'?

Many people believe that weight loss and weight gain are primarily down to the ratio of the number of calories coming into and out of the body. However, others believe that weight loss and gain are much more complex than this and that there are many contributing factors.

The concept of calories and weight loss can be confusing. You can learn more about here. We will also cover this important concept in detail in this article, focusing on whether weight loss is as simple as reducing your calories in vs. calories out ratio.

The Basics of Calories In vs. Calories Out

Calories in vs. calories out refers to the number of calories you consume through food compared with the number of calories you burn daily.

Your body uses energy (calories) to simply survive and perform basic functions, even when you’re at rest. You can increase your calorie expenditure by increasing your physical movement and raising your metabolic rate by building skeletal muscle.

For example, if you walk everywhere and eat a healthy diet, you’re likely to find weight loss easier than somebody who lives in a country where a sedentary lifestyle is the norm. This is because you’ll burn more calories on a daily basis and may have a higher metabolic rate.

The Complexity of Calories In vs. Calories Out

If you narrow it down to the bare minimum, eating fewer calories than you’re consuming is ultimately what will cause you to lose weight. However, as simple as the concept of calories in vs. calories out sounds when it comes to weight loss, it’s a little more complex.

There are multiple factors that contribute to the number of calories your body burns on a daily basis and how it uses the calories you consume in your diet. Let’s take a look at some of these factors.

Metabolic rate

Metabolic rate can vary depending on your age, genetics, body composition, and food intake. It’s a highly variable thing that quickly adapts to changes in your calorie intake. Reducing your calorie intake as an attempt to lose weight could cause your metabolic rate to slow down, meaning you burn fewer calories at rest.

Hormones

Several hormones influence your metabolic rate, including estrogen, progesterone, testosterone, and insulin. While these hormones naturally fluctuate over time, significant fluctuations, a lack of, or too much of these hormones can influence the way your body uses energy and make it harder for you to lose weight.

Leptin and ghrelin are the two main hunger hormones that influence how hungry and full you feel. Disruptions in leptin and ghrelin release in your body can cause you to feel hungrier, making weight loss more challenging.

Gut microbiome

The gut microbiome refers to all of the microorganisms that reside in your colon. The composition and diversity of your gastrointestinal microbiome influence your metabolism and nutrient absorption, thereby influencing how easy or difficult it is for you to lose weight.