When it comes to weight management, counting calories may not always work, but there’s no doubt that calories count. Quite simply, to lose weight, you need to burn more calories than you absorb. If you’re counting calories, you probably are already considering your basal metabolic rate (how many calories you burn without doing anything) as well as the calories you burn during exercise.
In addition, we also burn calories with non-exercise activity thermogenesis (NEAT) and even while eating and digesting the foods we consume.
Indeed, any time you eat, your body will need to expend energy (i.e., burn calories) to digest, absorb, and metabolize the food. In addition, some of those calories will be burned off as heat. This process is known as “diet-induced thermogenesis” (DIT) or the thermic effect of food (TEF). While the general formula for calculating the number of calories for the TEF is about 10% (e.g., if you eat 2,000 calories during the day, you’ll burn about 200 just to digest the food), some foods increase this process more than others.
With two-thirds of American adults considered overweight, many of us are looking for effective ways to manage our weight. So, a big question is, if you eat more foods with a higher thermic effect, can they boost fat loss?
The answer, of course, can be complicated and nuanced as it depends on several factors. This can include not only what your meal is made up of (as far as macronutrients as well as the quality of the foods) and your lean body mass. For example:
- Fat has 9 calories per gram and has a thermic effect of about 0 to 3%.
- Carbohydrates, on the other hand, have just 4 calories per gram with a thermic effect of between 5 and 10%.
- Protein is the most thermogenic food. It also provides 4 calories per gram but has a thermic effect of 20 to 30%.
What Affects the Thermic Effect of Food?
Foods that are higher in protein and carbs (as opposed to fat) are more likely to increase the thermic effect. Large meals also increase thermic effect of food more than smaller, more frequent meals. And plant-based diets may also play a role as do age, activity levels, and body weight. 1 Sour overall metabolism can be influenced by:
- How many calories you eat at each meal as well as throughout the day. Energy expenditure increases for up to eight hours after you eat as the body digests and stores the food you eat. And this effect is even greater when a larger meal is consumed for breakfast. 2
- Your macronutrients; for example, if you eat more protein, your TEF will be higher. If you eat more fat, your TEF will be lower.
- What types of food you eat. Higher-protein foods and higher-fiber foods take longer to digest, and therefore, the TEF is higher. So, a diet that’s higher in whole, nutrient-dense foods will have a higher TEF than a diet that’s made up of more refined, processed foods. 3
- How active you are. Being more physically active combined with eating a higher-protein diet can increase TEF. 4 In addition, both cardiovascular and resistance training (weightlifting) can help increase TEF. 5
- Genetics as well as hormone levels.
- The amount of lean mass you carry (i.e., people who carry more muscle burn more calories than those with less).
Can You Increase TEF?
Unfortunately, if all you do to try to lose weight is influence the thermic effect of food, you aren’t likely to be successful in your endeavor. That said, when combined with other weight-loss behaviors, it could nudge it in the right direction, and you may be able to do so by:
- Eating a few larger meals throughout the day rather than smaller, more frequent meals. And make sure you are eating enough and not cutting calories too much. In addition, following a regular meal frequency helps increase post-meal energy expenditure. 6
- Slowing down as you eat to ensure you chew your food completely. 7 In addition to increasing TEF, chewing food well before swallowing can also increase satiety after eating. 8
- Exercising regularly and ensuring you add resistance training to your plan to build more muscle.
- Striving for more NEAT by using a standing desk, taking exercise or movement breaks throughout the day, and doing household chores.
- Finding reasons to laugh more. Laughing out loud can increase calorie burning by up to 20%. 9
- Ensuring you’re getting enough quality sleep. And while you’re at it, cool down the temperature to 66°F to help improve sleep quality and potentially enhance metabolic benefits (via activation of brown fat). 10
- Drinking enough water, especially cool water first thing in the morning to wake up your metabolism. 11 In one small study, participants who drank about 2 tall glasses of water (600 ml) increased their metabolic rate by about 24 to 30% for about an hour to an hour and a half. 12
- Consuming foods and beverages that can help boost fat loss.
Foods That Boost Metabolism
Speaking of foods that can increase the thermic effect of food and thus metabolism, yes, they do exist. Here are 19 foods to include in your TEF-enhancing diet plan:
1. Protein! Because protein can have a TEF as high as 30%, ensuring you eat a higher-protein diet can help optimize your metabolism. Include some protein, such as meat, poultry, fish, eggs, dairy, or protein-rich plants like legumes, lentils, nuts, and seeds, with every meal. Protein-rich foods may also help fight the natural drop in metabolism as seen during weight loss by helping the body maintain muscle mass. 13, 14
High-protein diets (with about 30 to 35% of calories from protein) have also been found to help reduce appetite, 15 body weight, fat weight, and triglycerides 16 as well as increase satiety, thermogenesis, sleeping metabolic rate, protein balance, and fat burning. 17
2. Legumes, such as beans, chickpeas, green peas, and lentils, provide both protein and fiber (including resistant starch and soluble fiber), which require more calories to digest. These fibers also feed the microbiome in the gut, which produce short-chain fatty acids in return. The body then uses these fatty acids to help burn fat for energy and maintain stable blood sugar levels.
Partially due to their high amino acid content (e.g., arginine and glutamine), in one eight-week study, participants who consumed a legume-rich diet enjoyed a higher metabolism and lost 1.5 times more weight than folks on a control diet. 18
Another study found that adults and teens who eat ¾ cup of beans daily can weigh 6.6 to 7.3 pounds less than those who avoid the musical fruit, despite eating more calories per day on average. They also had smaller waists and a reduced risk of being obese and enjoyed lower systolic blood pressure. 19
3. Chili Peppers, or more specifically, the capsaicin found in chili peppers as well as cayenne pepper. Capsaicin is the compound that brings the heat, and with that heat comes an increase in metabolic rate of about 50 extra calories per day. That may not seem like a lot, but capsaicin has been shown to significantly decrease belly fat and reduce appetite and energy intake when consumed regularly. 20
While not all research agrees on how effective capsaicin is for boosting metabolism, one study estimates that just 2 mg of the compound before meals may reduce the calories (especially carbohydrate calories) consumed. 21
4. If you don’t enjoy the heat from spicy peppers, there’s a “non-burning version of capsaicin called dihydrocapsiate (DCT) that could have the benefits of peppers without the pungency.” One study found that non-spicy peppers can nearly double the energy expenditure after a meal over a placebo. The research also found that fat burning was increased. 22
5. Caffeine and Catechins. Best known for helping us peel open our eyes in the morning via a big mug of coffee or tea, caffeine has also been found to boost thermogenesis by between 8 and 11%. 24 In fact, consuming at least 270 mg of caffeine (as found in about 3 cups of coffee) may burn an extra 100 calories each day. 25 And when caffeine is combined with catechin (as in green and oolong teas), it may help increase daily fat burning by up to 17%. 26
These effects, however, aren’t the same for everyone and may vary depending on age, body weight (for example, fat burning was found to be higher in leaner women in one study 27), and other individual characteristics.
6. Whole grains. Because the body has to work harder to digest whole grains vs refined or processed grains, this can also help elevate the metabolism. Research, for example, found that when whole foods are eaten, the post-meal energy burning rose by up to 50% over more processed foods. 28 Some good choices of whole grains include quinoa, old-fashioned or steel-cut oats, brown rice, and ancient grains like amaranth or kamut, and sprouted whole wheat.
7. Avocado provides metabolism-supporting monounsaturated fats along with fiber and powerful antioxidants. Another food high in monounsaturated fats that may help the body burn calories is olive oil. 29
8. Yet for an even higher thermic effect, the best choice of fat may just be medium-chain triglycerides, or MCTs. Including two tablespoons of MCT oil in your daily diet could increase metabolic rate by up to five percent. 30 Research has found these unusual fats may not only help you manage your weight, but they may also support cognitive functioning.
9. Broccoli provides both calcium and vitamin C, which both have been shown to support a healthy metabolism. It’s also high in fiber, which can support an increase in thermogenesis.
10. Another high-fiber food to include in your metabolism-boosting diet: the humble apple, which is a good source of soluble fiber. One study found that for every 10-gram increase of soluble fiber found in the diet per day, there was a 3.7% reduction in belly fat over 5 years. 31
11. Ginger is one of many spices that may be able to help boost metabolism. In fact, drinks providing ginger (about 2 grams) in hot water and served with a meal have been shown to help increase calorie burning, decrease hunger, and enhance satiety. 23
12. Skip the mayo and go with mustard instead. According to one study, a teaspoon of mustard adds just 5 calories but can boost the metabolism by up to 25% for hours. 32
Foods that Decrease Metabolism
On the other end of the spectrum are foods that can actually make your metabolism slower. If you want to keep your metabolism revved up, foods to avoid include:
- Refined grains and other processed and packaged foods like white bread and pastas.
- Sugary beverages like soda, fruit juice, and energy drinks.
- Alcoholic beverages, which can negatively affect blood sugar and lower inhibitions, so you’re more likely to make unhealthy food choices.
- Cereals, including granola.
- Refined oils like soybean, canola, corn, sunflower, and safflower oils.
- Diet sodas and other artificially sweetened beverages, which may mess with the body’s normal metabolic response to sugar and increase appetite. 33
Thermic Effect of Food: A Wrap Up
Can eating more foods that have a higher thermic effect really help you lose weight? Alone, in truth, probably not much. While they may help boost the metabolism, it’s by a small amount for a short amount of time. Yet if foods with a higher thermic effect are combined with other metabolic-supporting habits (like regular exercise, staying active, quality sleep, and staying hydrated), they could help nudge you in the right direction. This is especially true if they improve diet quality by displacing less healthy foods and improve appetite management.
Instead of focusing on just specific foods to boost metabolism, choose a wide variety of whole foods that provide taste as well as nutrition while supporting a strong metabolism.