Digesting and processing food, including carbohydrates, proteins, and fats, also requires energy. In the world of nutrition, many foods and drinks are claimed to speed up metabolism, the reactions in the body that provide energy. In this article, we explore how our diet affects our metabolism and whether certain foods and drinks really do have a significant impact on metabolic rate.
A reliable source of metabolism is the sum of the reactions in our cells that provide the necessary energy for functions such as movement, growth, and development.
Many factors can affect metabolism, including age, diet, biological sex, physical activity, and health status. Basal metabolic rate is the energy needed to maintain vital body functions, such as breathing, at rest. It is the largest contributor to the number of daily calories burned – also known as total energy expenditure.
Digesting and processing food, including carbohydrates, proteins, and fats, also requires energy. This is known as the thermal effect of food (TEF). Some foods take more energy to break down than others, and this can increase your metabolism slightly.
For example, fat requires less energy to digest than proteins and carbohydrates. Proteins have the highest TEF of the three macronutrients.
Can certain foods speed up metabolism?
A person may think that certain foods and drinks can “speed up” metabolism, but this is not always the case. Some foods require more energy to digest than others, and some foods can slightly increase the rate of basal metabolism, but not by much.
What matters most is the total amount consumed with food. For example, the TEF, the energy required to digest food, varies depending on the macronutrient content of the food.
Here is the energy needed to digest macronutrients:
- Protein: 10-30% of the energy value of the protein consumed.
- Carbohydrates: 5-10% of the carbohydrates consumed.
- Fat: 0-3% of the fat consumed.
The body uses the most energy to break down and store proteins, so it has the highest TEF.
TEF accounts for about 10% of reliable sources of total daily energy expenditure. For this reason, a diet high in protein can help us burn more calories.
In addition, research shows that highly processed foods require less energy to digest than whole foods. This is likely due to the low fiber and protein content of highly refined foods.
Studies have also shown that a high-protein diet can increase resting metabolic rate (RMR), the number of calories burned at rest.
A study conducted in 2015 by a reliable source found that in people with a high-calorie diet, consuming high amounts of protein significantly increased 24-hour resting energy expenditure compared to low amounts of protein.
A study conducted in 2021 found that a high-protein diet consisting of 40% protein yielded higher total energy expenditure and increased fat-burning compared to a control diet containing 15% protein.
Other studies have also shown that high-protein diets increase daily energy expenditure compared to low-protein diets.
Do certain foods increase metabolism?
It’s clear that a high-protein diet can help people burn more calories each day, but what about specific foods? For example, compounds in chili peppers, green tea, and coffee can increase metabolism slightly.
A reliable source of caffeine can increase energy expenditure, so drinking caffeinated beverages such as coffee and green tea can slightly increase metabolism.
Studies show that consuming foods with green tea catechin extract can increase daily calorie intake by 260 calories when combined with weight-bearing exercise. It’s important to note that most studies in this area involve high doses of green tea extract, and the results may not apply to people who just drink green tea.
Some studies show that EGCG, a catechin found in green tea, can increase energy intake at doses of 300 milligrams (mg). For reference, green tea contains about 71 mg of a reliable source of EGCG per 100 milliliters serving.
Meanwhile, capsaicin in chili peppers can increase metabolic rate when taken in concentrated supplements. But the amount of this compound in a typical chili dish is unlikely to significantly affect metabolism.
Similarly, one study found that drinking a hot drink containing ginger powder with a meal can slightly increase TEF by about 43 calories per day. But this will not have a significant impact on overall energy expenditure or weight loss.
How to promote a healthy metabolism and body weight
To maintain and sustain a healthy body weight, it is important to focus on the overall quality and content of macronutrients in the diet rather than including or excluding certain foods.
As mentioned above, research shows that a diet rich in protein and whole foods significantly increases energy expenditure compared to diets low in protein and high in ultra-pasteurized foods.
Although consuming moderate amounts of foods and beverages designed to improve metabolisms, such as spicy foods, ginger, and green tea, will likely not cause harm, it is unlikely to have a significant effect on energy expenditure or body weight.
A well-balanced diet with plenty of protein and fiber, such as vegetables, fruits, nuts, seeds, and beans, will support a healthy metabolism and improve overall health.
Getting enough physical activity and maintaining healthy muscle mass can also help improve overall energy expenditure.
Weight training can be particularly effective. A 2015 study found that weight training for 9 months can increase RMR by as much as 5% in healthy adults. And a 2020 review found that weight training increases RMR, leading to an average calorie increase of about 96 calories per day compared to the control group.