Caffeine is a natural stimulant found in coffee, carbonated sodas, tea, and energy drinks. Coffee—the most common source of caffeine—may have anti-inflammatory effects. However, caffeine alone doesn’t appear to have the same effect against inflammation.
Research is mixed on how caffeine affects inflammation. Inflammation occurs when your immune system releases chemicals to fight off harmful substances. Chronic (long-term) inflammation can lead to asthma, heart disease, and some cancers.
People often get caffeine from coffee, which is generally believed to have anti-inflammatory effects. One study found that consuming more coffee was associated with lower inflammatory markers (blood tests that detect inflammation).
Another study found that, compared to non-coffee drinkers, those who drank at least 4 cups of coffee daily had reduced inflammatory markers, including C-reactive protein (CRP). These results were consistent in people drinking caffeinated and non-caffeinated coffee.
However, some studies have found coffee and caffeine to increase inflammation, depending on the person. Caffeine alone, not necessarily in the form of coffee, may contribute to some inflammation.
While caffeine alone can either increase or decrease inflammation, other factors can influence its role in inflammation, including:
- The amount of antioxidants in a drink: The antioxidant compounds in caffeinated teas can vary widely depending on the type of tea and its production. For instance, studies show that green tea is more anti-inflammatory than black tea.
- The type of coffee: Coffee’s anti-inflammatory effects can vary depending on the type of coffee and how the beans are processed or roasted. Green coffee (made from unroasted beans) contains more chlorogenic acid, an anti-inflammatory compound, than roasted black coffee.
- The added ingredients: Cream, sugar, or milk are often added to coffee and tea, which can contribute to inflammation.
Besides its potential to decrease or increase inflammation, caffeine can have these other effects on your health:
- Increased alertness: This is the most common effect of caffeine. Caffeine stimulates the central nervous system, making you feel more awake. However, consuming too much caffeine can lead to restlessness, excitement, shakiness, and insomnia (trouble sleeping).
- Improved exercise: There is evidence that caffeine can improve muscular endurance, movement velocity, muscular strength, and other sport-specific actions. Caffeine may also be beneficial for aerobic endurance.
- Better digestion: Caffeine increases the movement of food through the digestive tract, which may support regular bowel movements and help prevent constipation.
- Protection against damage: Caffeine has antioxidant properties, meaning it helps counteract the harmful effects of compounds called free radicals to protect cells from oxidative stress and damage. It can also reduce skin damage from ultraviolet (UV) radiation.
- Changes to heart health: A review of studies found that higher coffee intake resulted in a lower risk of heart failure. However, research has also shown that caffeine consumption may increase your blood pressure and raise your risk of an irregular heart rhythm.
There is also evidence that caffeine may decrease the risk of depression, increase pain threshold, and boost immune and respiratory health.
Consuming more than the recommended amount of caffeine can cause a wide range of symptoms. These include:
- Increased heart rate
- High blood pressure
- Insomnia
- Anxiety
- Jitters
- Stomach upset
- Headache
- Nausea
- Heart palpitations
Keep in mind that caffeine’s effects vary by person, and you may be more likely to experience side effects if you’re sensitive to caffeine.
The U.S. Food and Drug Administration (FDA) considers 400 milligrams of caffeine (about two or three 12-ounce cups of coffee) safe daily. This amount is generally not associated with negative effects. There are a few ways to ensure your caffeine consumption stays within the recommended range:
- Read product labels: Caffeine may be in products you don’t expect, such as protein bars, chewing gum, and certain over-the-counter medications. If caffeine is added as a standalone ingredient, it will be on the list of ingredients.
- Drink energy drinks cautiously: The amount of caffeine in energy drinks varies widely. Drinks can contain 54-328 milligrams of caffeine per 16 ounces. In some cases, you can almost reach the maximum daily amount of caffeine after one drink.
- Switch to decaffeinated drinks: Decaf coffees and teas have less caffeine than their regular counterparts, so if you’re trying to lower your caffeine intake, these may be a good option. Decaf coffee and teas still contain some caffeine, and the amount varies depending on the drink.
Various environmental factors are involved with inflammation. The following diet and lifestyle changes may help prevent or manage symptoms related to inflammation:
- Reduce consumption of processed or packaged foods.
- Increase intake of anti-inflammatory foods, such as blueberries, apples, and broccoli.
- Avoid or quit smoking.
- Avoid alcohol.
- Limit stress.
- Reduce exposure to toxic chemicals.
- Get adequate sleep.
- Engage in regular exercise.