Even if two foods share the same number of calories, there is a big difference in their effect on your body.
Calories are calories, at least from a thermodynamic point of view.This is defined as the amount of energy required to raise the temperature of 1 kilogram of water by 1 degree. Celsius (2.2 lbs x 1.8 degrees Fahrenheit).
But when it comes to health and your body’s energy balance, not all calories are equal.
For example, some studies have reported that a high-protein, low-carbohydrate, or combination of the two diets results in significantly more weight loss than diets containing other levels of fat, protein, and carbohydrates.
If all the calories in a food are the same, you cannot expect to see a difference in weight loss between people who eat the same number of calories consumed by different types of foods.
Nutritionists like me know that there are many factors that affect what calories mean to your body. So far, what we understand about calories and nutrition is:
The energy that is actually available to your body
In the late 1800s, chemist WO Atwater and his colleagues devised a system for understanding the amount of energy, or calories, contained in various foods. Basically, he burned food samples and recorded how much energy they released in the form of heat.
However, not all the energy of food that can burn in the laboratory is actually available to your body. What scientists call metabolizable energy is the difference between the total energy consumed by food and the energy that is excreted out of the body by feces and urine without being digested. Atwater devised the percentage of calories that can actually be metabolized for each of the three major nutrients: protein, carbohydrates and fat.
According to the Atwater system, 1 gram of each major nutrient is estimated to provide a specific calorie count. The USDA still uses these calculations today to calculate the official calorie count for all foods.
How much energy to use
What you eat can affect what scientists call your body’s energy expenditure. It’s the energy you need to stay alive-the energy you use to breathe, digest, maintain your blood flow, etc.-along with what you exercise and exert your body. You may have heard this called metabolism.
Dietary quality can alter the body’s energy expenditure, also known as the heat effect of food. For example, one study found that people eating the same number of calories per day, but eating either a low-carb diet or a low-fat diet, differed in their total energy expenditure of about 300 calories per day. did. Those who ate a very low-carb diet used the most energy, while those who ate a low-fat diet used the least.
In another study, a high-fat diet reduced total energy expenditure compared to a high-carbohydrate diet. Other researchers reported that using carbohydrates instead of fat did not change energy expenditure, but people who increased their protein intake to 30% to 35% of their diet used more energy. Did.
For good reason, nutrition labeling food labels aren’t just about calories.
In general, a diet high in carbohydrates, fats, or both increases energy expenditure by 4% to 8%, while a diet high in protein increases the resting metabolic rate by 11% to 14%. Protein is hard to break, so it has a high heat effect. Although these fluctuations are not large, they can contribute to the prevalence of obesity by promoting subtle average weight gain.
Quality of calories you eat
Dietitians pay attention to the glycemic index and glycemic load of foods, that is, how fast and how much they raise blood sugar levels. Elevated blood sugar causes the release of insulin, which in turn affects energy metabolism and the storage of excess energy as fat.
Foods such as white rice, cakes, cookies and chips all have a high glycemic index / load. Green vegetables, raw peppers, mushrooms and legumes all have a low glycemic index / load. There is some evidence to suggest that foods with a low glycemic index / load may be suitable for regulating glycemic levels, regardless of the calories they contain.
When people eat high glycemic index / high load foods, the reward center in the brain becomes brighter, highlighting the fun and addictive effects of foods such as candies and white bread.
Dietary fiber content should also be considered. Your body cannot digest the fiber contained in vegetable foods such as fruits, vegetables, whole grains and beans as energy. Therefore, foods high in fiber tend to have less metabolic energy and help you feel full with less calories.
Food provides more than calories.
Empty calories (calories from foods with minimal or no nutritional value) are another factor to consider. Things like white sugar, soft drinks, and many super-processed snacks do not offer many benefits in the form of proteins, vitamins, or minerals along with calories. Conversely, there are nutrient-rich foods that are rich in nutrients and fiber and relatively low in calories. Examples are spinach, apples and beans.
And don’t think of empty calories as neutral. Dietitians consider them harmful calories because they can have a negative effect on your health. The biggest contributors to weight gain are potato chips, potatoes, sugared beverages, and both processed and raw meat. On the other hand, foods that are inversely proportional to weight gain are vegetables, whole grains, fruits, nuts and yogurt.
More healthy than calories and weight
When it comes to weight loss, there is no doubt that the difference between the number of calories burned and the number of calories burned by exercise is the most important factor. But don’t be fooled. Weight affects health and longevity, but weight loss alone is not the same as health.
Yes, some high-protein diets seem to promote weight loss, at least in the short term. However, epidemics say that in the areas where people live the longest (nearly 100 years on average), they mainly eat plant-based diets, with very little or no animal-based protein, fats as mono and Fat that you know is low or moderate in the form of polyunsaturation.
I often hear friends and clients say, “It’s carbs that make me fat” and “I need a low carb diet.” But these complaints drive nutritionists like me. Carbohydrates include not only foods such as Coca-Cola and candy cane, but also apples and spinach. Reducing simple carbohydrates such as soft drinks, refined flour bakery items, pasta and sweets will definitely have a positive impact on your health. However, eliminating carbohydrates such as vegetables and fruits has the opposite effect.
A plant-based diet high in plant-based proteins and carbohydrates, primarily from vegetables, fruits, nuts and legumes, is for lifespan and prevention of chronic diseases such as heart disease, cancer, high blood pressure and many other conditions. It is the healthiest diet researchers know.
The modern Western diet suffers from an increase in the amount of calories burned and a decline in the quality of calories burned at the same time. And researchers know that the calories in different foods have different effects on satiety, the insulin response, the process of converting carbohydrates into body fat, and metabolic energy expenditure.
If your health is a concern, rely more on the quality of the calories you burn than on the calorie count.
Written by Terezie Tolar-Peterson, Associate Professor of Food Science, Nutrition and Health Promotion, Mississippi State University.
This article was first published in The Conversation.
