Person about to take a sip of coffee while wondering if caffeine makes you gain weight

Does Caffeine Make You Gain Weight?

Written on June 18, 2023 by Sendra Yang, PharmD, MBA. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

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The smell of freshly brewed coffee in the morning is something many people look forward to every day. Around 154 million United States adults report drinking coffee, and 49% drink coffee daily. [1] Caffeine is the main component in coffee that makes it so widely consumed, especially in the mornings, to help people wake up. Teas, chocolates, and soft drinks also contain caffeine. [2] Every day, up to 80% of adult Americans consume caffeine. [3]

People drink coffee in the mornings because caffeine can increase alertness. [4] Frequently people sip their coffee without thinking about how it can affect their bodies. But one of the questions to consider is, “Does caffeine make you gain weight?” To better understand how caffeine can impact your body, it’s a good idea to start with what caffeine is and some of its other effects before diving into caffeine and weight gain.

About Caffeine

The scientific name for caffeine is methylxanthine or, more specifically, 1,3,7-trimethylxanthine. [4] Caffeine is metabolied in the liver and absorption is mostly complete 45 minutes after consumption.[4] Caffeine can cross over from the blood to the brain and spread throughout the body, peaking in the blood at 15 minutes to two hours post-consumption. [4]

Natural caffeine exists in coffee beans, tea leaves, cacao pods, and kola nuts. [2] Caffeine can also be made in the lab and added to some medicines, foods, and drinks. [2] The U.S. Food and Drug Administration considers 400 milligrams of caffeine a safe amount for daily consumption in healthy adults. [5] Here are some sources of caffeine and the varying amounts in each [5]:

  • Coffee: A freshly brewed 8-ounce cup of coffee has around 95 milligrams of caffeine, whereas an instant cup contains close to 60 milligrams, and a decaffeinated cup has 4 milligrams.
  • Tea: A cup of black tea has about 47 milligrams of caffeine, and a cup of green tea has around 28 milligrams.
  • Soda: A regular or diet 12-ounce can of soda can have up to 40 milligrams of caffeine.
  • Chocolate: An ounce of dark chocolate has around 24 milligrams of caffeine, and milk chocolate has one-quarter less the amount.
  • Energy drinks: An 8-ounce cup of an energy drink contains around 85 milligrams of caffeine.
  • Supplements: Caffeine supplements have around 200 milligrams in each tablet.

Caffeine's Effects on the Body

Caffeine is commonly referred to as a stimulant because of its numerous stimulatory effects on the body. [2,4] The effects of caffeine on various organs and systems in the body are as follows [4]:

  • Brain: increases mental performance and alertness, can lead to anxiety and insomnia, may enhance the effect of medicines like acetaminophen for headache and pain, may reduce risk of depression and Parkinson’s disease
  • Lungs: used for apnea treatment in premature infants with minimal lung function improvement in adults
  • Liver: may decrease changes of liver fibrosis, cirrhosis, and cancer
  • Kidneys and urinary tract: increases urine in high doses
  • Cardiovascular system: increase in blood pressure with some tolerance over time
  • Endocrine system: decreases insulin sensitivity, but tolerance may develop
  • Reproductive system: may diminish the growth of the fetus and increase pregnancy loss

Everlywell Weight Loss Support

Caffeine and Weight Gain

So, does caffeine make you gain weight? This is an interesting question because the answer is not as simple as it may seem. Based on the stimulatory effects of caffeine, you may conclude that caffeine will make you lose weight. Some studies have reported that caffeine can reduce appetite and increase metabolism. [6-8] Additionally, a large prospective study examined the relationship between long-term weight change and caffeine intake for men and women. [9] The study found that increases in caffeine consumption in the long term were associated with slightly less weight gain. [9]

However, a different effect of caffeine may lead to weight gain. Caffeine is also found to decrease insulin sensitivity. [10] As you become less sensitive to insulin and more insulin resistant, your chance of developing diabetes rises. [11] The increased levels of sugar and insulin in your blood send the message to your liver to store the excess blood sugar as fat, leading to weight gain. [11] Though a study found that coffee intake for six months does not impact insulin sensitivity. [12] The polyphenols in coffees and teas are thought to potentially offset the harmful effects of caffeine. [13]

Something else to consider is that high-calorie soft drinks and the sugar added to teas and coffee may lead to weight gain [4] A study further reports that caffeine may have mildly addictive properties associated with weight gain when added to sugar-sweetened beverages. [14]

Weight Management with Everlywell

If you are concerned about gaining weight and want to discuss your weight loss goals with a healthcare provider, consider telehealth via Everlywell. You can schedule a meeting with a certified clinician to help you manage your weight through a telehealth weight loss option.

Conditions That May Have Weight Gain as a Symptom

Genetic Obesity: What Does It Mean?

Can Undiagnosed Diabetes Cause Weight Gain?


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  2. Caffeine. MedlinePlus. Accessed June 12, 2023.
  3. Too much coffee? American Psychological Association. Accessed June 12, 2023.
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  10. Keijzers GB, De Galan BE, Tack CJ, Smits P. Caffeine can decrease insulin sensitivity in humans. Diabetes Care. 2002;25(2):364-9. doi: 10.2337/diacare.25.2.364.
  11. Insulin resistance and diabetes. Centers for Disease Control and Prevention. Last reviewed June 20, 2022. Accessed June 12, 2023.
  12. Alperet DJ, Rebello SA, Khoo EY, Tay Z, Seah SS, Tai BC, Tai ES, Emady-Azar S, Chou CJ, Darimont C, van Dam RM. The effect of coffee consumption on insulin sensitivity and other biological risk factors for type 2 diabetes: a randomized placebo-controlled trial. Am J Clin Nutr. 2020;111(2):448-458. doi: 10.1093/ajcn/nqz306.
  13. Cherniack EP, Buslach N, Lee HF. The Potential Effects of Caffeinated Beverages on Insulin Sensitivity. J Am Coll Nutr. 2018;37(2):161-167. doi: 10.1080/07315724.2017.1372822.
  14. Keast RS, Sayompark D, Sacks G, Swinburn BA, Riddell LJ. The influence of caffeine on energy content of sugar-sweetened beverages: 'the caffeine-calorie effect'. Eur J Clin Nutr. 2011;65(12):1338-44. doi: 10.1038/ejcn.2011.123.
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