Not All Calories Are Equal - How Food Types Affect Your Body

A calorie is a calorie, at least from a thermodynamic standpoint

But when it comes to health and your body's energy balance, not all calories are created equal

For example, some studies report that diets high in protein, low in carbohydrates, or a combination of the two do lead to better weight loss than diets containing other fats, proteins, and carbohydrates

If every calorie in the food is the same, you wouldn't expect to see a difference in weight loss in people who eat the same number of calories from different types of food

Here's what we know about calories and nutrition so far

your body can get energy

In the late 1800s, chemist WO Atwater and his colleagues devised a system to calculate how much energy—that is, how many calories—in different foods

However, not all the food energy that can be burned in a lab can be absorbed by your body

According to the Atwater system, one gram of each macronutrient is estimated to provide a certain number of calories

how much energy do you use

What you eat affects what scientists say is your body's energy expenditure

Diet quality can alter the body's energy expenditure, which is also known as the thermic effect of food

In another study, a high-fat diet resulted in lower total energy expenditure than a high-carb diet

Nutrition Facts food labels contain more than just calorie counts—and for good reason

In general, a diet high in carbohydrates and fat, or both, increases energy expenditure by 4%-8%, while a diet high in protein increases metabolic rate by 11%-14%

the quality of the calories you eat

Nutritionists look at a food's glycemic index and glycemic load -- that is, how quickly and how much a food increases your blood sugar levels

Foods such as white rice, cakes, cookies, and chips are all high on the glycemic index/load

When people eat high-glycemic/high-load foods, reward centers in the brain activate, highlighting the pleasurable and addictive effects of foods like candy or white bread
.

The fiber content of the food is another factor to consider
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Your body can't digest fiber -- found in plant foods like fruits, vegetables, whole grains, and legumes -- for energy
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As a result, high-fiber foods tend to contain less metabolic energy, making you feel full while consuming fewer calories
.

"Empty heat" is another factor to consider
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Like white sugar, soft drinks, and many ultra-processed snacks, even if they do, they don't provide much protein, vitamins or minerals and their calories
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The opposite is nutrient-dense foods that are high in nutrients or fiber but relatively low in calories, such as spinach, apples, and beans
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Don't think of empty heat as neutral
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Nutritionists consider them harmful calories because they can negatively impact health
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Potato chips, chips, sugar-sweetened beverages, processed and unprocessed meats are the biggest contributors to weight gain
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On the other hand, foods that were inversely associated with weight gain were vegetables, whole grains, fruits, nuts, and yogurt
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Better Health than Calories and Weight

Needless to say, the difference between the number of calories burned and the number of calories produced through exercise is the most important factor when it comes to weight loss
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But don't deceive yourself
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While weight plays an important role in health and longevity, losing weight by itself does not equate to good health
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Yes, some high-protein diets seem to promote weight loss, at least in the short term
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But epidemiologists know that in regions with the longest lifespans (average lifespans approaching 100 years), people's diets are largely plant-based, with very low or no animal protein and low or moderate levels of monounsaturated fats and polyunsaturated fats.
Unsaturated fats
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I often hear friends or clients say "carbs are making me fat" or "I need a low-carb diet
.
" But these complaints drive dietitians crazy
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Carbohydrates include Coca-Cola and candy canes, but also apples and spinach
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Cutting back on simple carbohydrates like soft drinks, refined flour baked goods, pasta and sweets will definitely have a positive effect on your health
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But skipping carbohydrates like vegetables and fruits can have the opposite effect
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A plant-based diet is rich in plant-based proteins and carbohydrates, mainly from vegetables, fruits, nuts, and legumes
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As far as researchers know, this is the healthiest diet for longevity and protection against heart disease, cancer, high blood pressure and many other diseases
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What the modern Western diet suffers from is an increase in caloric expenditure accompanied by a decrease in the quality of caloric expenditure
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Researchers now know that calories in different foods have different effects on satiety, insulin response, the conversion of carbohydrates to body fat, and the expenditure of metabolic energy
.

When it comes to your health, think more about the quality of the calories you consume than the number of calories
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By Terezie Tolar-Peterson, associate professor of food science, nutrition and health promotion at Mississippi State University
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