Caffeine: How much is too much?
Caffeine has its perks, but it can pose problems too. Find out how much is too much and if you need to curb your consumption.
By Mayo Clinic StaffIf you rely on caffeine to wake you up and keep you going, you aren't alone. Caffeine is used daily by millions of people to increase wakefulness, alleviate fatigue, and improve concentration and focus.
How much is too much?
Up to 400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults. That's roughly the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two "energy shot" drinks. Keep in mind that the actual caffeine content in beverages varies widely, especially among energy drinks.
Although caffeine use may be safe for adults, it's not a good idea for children. Adolescents should limit caffeine consumption. Avoid mixing caffeine with other substances, such as alcohol.
Even among adults, heavy caffeine use can cause unpleasant side effects. And caffeine may not be a good choice for people who are highly sensitive to its effects or who take certain medications.
Women who are pregnant or who are trying to become pregnant and those who are breastfeeding should talk with their doctors about limiting caffeine use.
Read on to see if you may need to curb your caffeine routine.
You drink more than 4 cups of coffee a day
You may want to cut back if you're drinking more than 4 cups of caffeinated coffee a day (or the equivalent) and you're experiencing side effects such as:
- Migraine headache
- Insomnia
- Nervousness
- Irritability
- Restlessness
- Frequent urination or inability to control urination
- Stomach upset
- Fast heartbeat
- Muscle tremors
Even a little makes you jittery
Some people are more sensitive to caffeine than are others. If you're susceptible to the effects of caffeine, just small amounts — even one cup of coffee or tea — may prompt unwanted effects, such as restlessness and sleep problems.
How you react to caffeine may be determined in part by how much caffeine you're used to drinking. People who don't regularly drink caffeine tend to be more sensitive to its negative effects. Other factors may include genetics, body mass, age, medication use and health conditions, such as anxiety disorders.
- Share
- Tweet
Products and Services
- Book: The Mayo Clinic Diet
- The Mayo Clinic Diet Online
- Book: Mayo Clinic on Digestive Health
- Book: The Mayo Clinic Kids’ Cookbook
See also
- Healthy-eating habits
- 5 strategies to improve eating habits
- Reduce sugar in your diet
- Acai berries
- Add flax to your diet
- Added sugar
- Alcohol use
- Alkaline water
- Are energy drinks bull?
- Art of Healthy Eating
- Artificial sweeteners
- 2015-2020 Dietary guidelines
- Breast-feeding nutrition: Tips for moms
- Butter vs. margarine: What's healthier?
- Is caffeine dehydrating?
- Can whole-grain foods lower blood pressure?
- Carbohydrates
- Chart of high-fiber foods
- Cholesterol: Top foods to improve your numbers
- Coffee and health
- Diet soda: Is it bad for you?
- Dietary fats
- Dietary fiber
- Do you drink enough water?
- Prickly pear cactus
- Don't go cuckoo for coconut water
- Make healthy snack choices
- Eat more of these key nutrients!
- Eggs: Bad for cholesterol?
- Energy drinks
- Fat grams
- Fiber: How to get your fill
- Fit more fiber into your diet
- Flaxseed for breakfast? You bet!
- Foods for healthy skin
- Grape juice health benefits
- Health-boosting nutrients
- Is chocolate healthy?
- Healthy eating: What are legumes, anyway?
- Healthy heart for life: Avoiding heart disease
- Mayo Clinic Healthy Weight Pyramid tool
- High-fructose corn syrup
- High-protein diets
- Alcohol during the holidays: 4 ways to sip smarter
- Takeout containers
- Is sea salt healthier than table salt?
- Is there more to hydration than water?
- Juicing
- Depression and diet
- Monosodium glutamate (MSG)
- MUFAs
- Multigrain vs. whole grain
- Need a snack? Go nuts!
- Need more fiber? Do it the easy way
- Nutrition Facts label
- Nuts and your heart: Eating nuts for heart health
- Olive oil
- Omega-6 fatty acids
- Phenylalanine
- Protein: Heart-healthy sources
- Healthy eating plans
- Reduce sugar in your diet
- Health foods
- High-fiber diet
- Portion control
- Planning healthy meals
- Social eating can be healthy and enjoyable
- Sodium
- Sodium: Look beyond the saltshaker
- Stevia
- Tap water or bottled water: Which is better?
- Taurine in energy drinks
- Time to cut back on caffeine?
- Trans fat: A double whammy
- Trans fat
- Trans fat substitutes: Not always better
- Underweight: Add pounds healthfully
- Daily water requirement
- Water softeners and sodium
- Functional foods
- What's considered moderate alcohol use?
- What to know before you juice
- What's the difference between added sugars and total sugars?
- What's the difference between juicing and blending?
- Yerba mate