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Metabolism Myths and Facts

Contributors: Esther Ellis, MS, RDN, LDN

Published: April 30, 2019

Reviewed: April 23, 2021

4 Metabolism Myths and Facts
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Why can one person eat like a growing teenager and not gain a pound, while another person's every indulgence shows up on the scale? Chalk it up to individual differences in metabolism, muscle mass and physical activity. Metabolism is the process by which our bodies convert what we eat into the energy we need to survive and function.Twitter Logo  It powers everything from breathing to blinking. A fast metabolism is like a hot furnace that burns through fuel (calories) quickly. A slow metabolism needs less fuel to keep a body running.

Claim: Our metabolic rates can't change.
The truth: While it's true that genetics help determine our metabolic rates, we can boost metabolism by increasing lean muscle mass. Muscle is metabolically active, which means that people with lean, muscular bodies need more energy to function than people with a higher percentage of body fat.

Our muscle mass decreases as we age, and this contributes to a slower metabolic rate. But you can counteract this process by picking up the weights to help lessen this decline.

Claim: A diet of green tea and chili peppers will boost metabolism.
The truth: No magic food will speed up metabolism. Some studies have shown that green tea and hot chilies temporarily boost metabolic rates, but the lift isn't very significant.

The path to a healthy lifestyle includes a balanced eating pattern filled with nutrient-rich foods.

Claim: Eating late at night slows metabolism.
The truth: There is little evidence to support the fact that eating after 8 p.m. causes weight gain. However, you may be more likely to snack mindlessly in the evenings while watching television.

Eat regular meals and snacks throughout the day to prevent extreme swings in hunger and fullness. If you're eating later in the evening, do so mindfully and put away the snacks when you're satisfied.

Claim: Very low calorie diets and skipping meals can jumpstart weight loss.
The truth: Creating a large calorie deficit in attempts to lose weight can backfire. Our bodies are smart and programmed for survival. Severely limiting calories can make your body think it's entering a famine, and that it needs to do more with fewer calories. Your body adapts to the restricted caloric intake, and uses fewer calories to perform the same tasks.

Resist the urge to diet and instead prioritize healthful foods, including whole grains, legumes, vegetables and fruits, and fun physical activity. Don't forget about stress management and proper sleep. These healthy lifestyle behaviors contribute to overall well-being.

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