Coffee is one of the most popular beverages in the world.

However, the effects of coffee on weight management are slightly mixed.

Black coffee — without any additional ingredients — is very low in calories and may help you achieve a healthy weight.

Coffee is low in calories

When trying to lose weight, you have to create a calorie deficit. You can do this either by increasing physical activity or consuming fewer calories.

An easy way to reduce calorie intake is to choose lower-calorie beverages. For example, replacing just 1 cup (240 ml) of a high-calorie, sugar-sweetened beverage with the same amount of water may lead to over 4 pounds (1.9 kg) of weight loss over 6 months .

By itself, coffee is a very-low-calorie beverage. In fact, 1 cup (240 ml) of brewed coffee has only 2 calories.

However, coffee only contains this minuscule number of calories if you drink it black — without adding sugar, milk, or any other ingredients.

If you’re attempting to reduce your total calorie intake, replacing high-calorie beverages — such as soda, juice, or chocolate milk — with plain coffee may be a good place to start.

Caffeine may boost metabolism

Caffeine is a natural stimulant commonly found in coffee, tea, and soda. Per serving, coffee typically contains the highest amount of caffeine of these three beverages.

One cup (240 ml) of brewed coffee offers about 95 mg of caffeine. Still, the caffeine content varies depending on the type of bean, roasting style, and preparation .

Caffeine may improve your metabolism — a measure of how many calories your body burns each day. This is one reason why caffeine is included in many weight loss supplements.

However, large doses of caffeine may be required to significantly influence metabolism.

For example, one study found that a caffeine dose of 4.5 mg per pound of body weight (10 mg per kg) increased metabolism by up to 13%. This would equal 680 mg of caffeine — a whopping 7 cups (1,660 ml) of coffee for someone who weighs 150 pounds (68 kg).

Still, some research shows that regular caffeine intake may improve body weight maintenance and weight loss.

In one study, an increase in caffeine intake was associated with less weight gain over 12 years. Yet, the participants who consumed the most caffeine were only about 1 pound (0.4–0.5 kg) lighter than those with lower caffeine intakes

A different study looked at people who successfully lost weight. Those who consumed the most coffee and caffeine were more successful at maintaining their weight loss over time

Caffeine may reduce your appetite

Caffeine may also help reduce your appetite.

Appetite is controlled by many different factors, including nutrient composition of meals, hormones, and activity levels. Drinking caffeinated coffee may reduce levels of the hunger hormone ghrelin .

Additionally, studies show that drinking caffeinated coffee may reduce the number of calories you consume throughout the day, compared to not drinking it .

However, the research surrounding caffeine as an appetite suppressant is conflicting, and some studies report that caffeine has little to no effect on feelings of fullness .

Thus, more studies are necessary.