How Coffee Affects Diabetes

Coffee is a popular beverage that many people enjoy in the morning and/or throughout the day. Studies have shown that coffee has a beneficial effect on certain illnesses such as cardiovascular disease, Alzheimer’s, Parkinson’s, and certain cancers.

Studies also suggest that increasing coffee consumption may lower the risk of developing type 2 diabetes. But for individuals who already have type 2 diabetes, drinking coffee or increasing the intake of the beverage could be harmful.

Learn more about how coffee affects diabetes.

couple drinking coffee

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Does Coffee Prevent Diabetes?

Known as an antioxidant-rich beverage, coffee also has:

  • Vitamins
  • Minerals
  • Caffeine
  • Bioactive substances

The antioxidant properties in coffee include:

  • Chlorogenic
  • Ferulic
  • N-coumaric acids

Studies have shown that the antioxidant properties in coffee are one of the reasons why it is beneficial to human health. One of the benefits includes reducing the risk of developing type 2 diabetes.

Epidemiological studies show moderate coffee consumption, such as consuming three to four cups of coffee per day, may lower the risk of developing type 2 diabetes by 25%. This is compared to consuming no coffee or less than two cups. The study also shared that the intake of both caffeinated and decaffeinated coffee may decrease type 2 diabetes risk.

Drinking Coffee When You Have Diabetes

Diabetes is a condition that causes blood sugar levels that are higher than normal and the body can’t properly create and use insulin.

  • With type 1 diabetes, the body doesn’t produce insulin. This is a hormone that helps glucose go from the bloodstream into the cells of the body.
  • With type 2 diabetes, which is most common, the body doesn’t produce insulin properly.

Diabetes can be controlled through proper diet, exercise, and medication or insulin that is prescribed by a healthcare provider.

Another type of diabetes is gestational diabetes. This can start when a woman’s body is not able to make and use all the insulin that it needs for the pregnancy. This diagnosis doesn’t mean that a patient had diabetes prior to pregnancy or a diagnosis will happen after conception. Gestational diabetes can be a temporary condition.

The best way to manage diabetes is through diet, exercise, and creating a plan with your healthcare provider to keep your blood sugar controlled.

Although caffeine may help reduce the risk of diabetes, for those who have diabetes, it could create an issue. Studies show that caffeine can impair glucose tolerance and decrease insulin sensitivity.

Effects of Caffeine

The chlorogenic acid and other phenolic compounds found in coffee are known to interfere with glucose transporters and decrease insulin sensitivity. Additionally, caffeine overall is known to impair glucose tolerance and also decrease insulin sensitivity.

In a study, seven trials were conducted. Five of the seven studies suggested that caffeine intake prolongs the period of high blood glucose levels and increases blood glucose levels. The study suggested that more clinical trials should be conducted to confirm the relationship between glycemic control with diabetes patients and caffeine intake.

Effects of Added Ingredients

Although coffee in its pure form is known to have health benefits, many individuals want to reach for the additives to perfect that cup of java. Whether it is cream or non-caloric artificial sweeteners, the added sugar is not the best option for individuals with diabetes.

Adding sugar, syrups, non-caloric artificial sweeteners, and creams can have a negative effect on diabetes patients due to the sugar and carbohydrate content.

One study concluded that non-caloric artificial sweeteners may induce glucose intolerance and alter the gut microbiome in humans.

It is important to have a conversation with your healthcare provider in regard to consuming coffee and adding sugar, sweetener, and other items to your drink. This is an important conversation to have so you can choose the right options. Your healthcare provider can give the best recommendation based on your individual specific needs.

Other Studies

Studies show that drinking green tea and coffee is associated with a lower death risk. Individuals who have type 2 diabetes are known to be at a higher risk for:

  • Circulatory diseases
  • Cancer
  • Bone fractures
  • Dementia

Due to the bioactive compounds in coffee and green tea, studies suggest that these beverages may have health benefits. Studies also show that drinking two or more cups of coffee along with four or more cups of green tea was associated with a 63% lower risk of death over a five-year period.

Yet, more research needs to be conducted to explore the impact of coffee and green tea both separately and combined.

Ask Your Healthcare Provider About Drinking Coffee

If you have diabetes, it is extremely important to talk to your healthcare provider about the consumption and amount of coffee, tea, and other beverages that may affect your condition. Have a list of questions prepared so you know what to include in your diet.

A Word From Verywell

Coffee is a beverage that is enjoyed by many people. Depending on preference, some love all the flavored additions that come with a cup of coffee. If you have diabetes, it is important to speak with your healthcare professional regarding the best options when it comes to consuming coffee. It is also important to have a conversation with your healthcare provider regarding lifestyle habits, diet, and exercise.

Diabetes can be managed with proper care, education, and choices. If an individual has a family history of diabetes, it is important to speak with your healthcare provider to learn about preventative lifestyle choices that you can make to stay healthy.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  7. Dewar L, Heuberger R. The effect of acute caffeine intake on insulin sensitivity and glycemic control in people with diabetes. Diabetes Metab Syndr. 2017 Dec;11 Suppl 2:S631-S635. doi:10.1016/j.dsx.2017.04.017

  8. Suez J, Korem T, Zilberman-Schapira G, Segal E, Elinav E. Non-caloric artificial sweeteners and the microbiome: findings and challenges. Gut Microbes, 6:2, 149 155, (2015). doi:10.1080/19490976.2015.1017700

  9. Komorita Y, Iwase M, Fujii H, et al. Additive effects of green tea and coffee on all-cause mortality in patients with type 2 diabetes mellitus: the Fukuoka Diabetes Registry. BMJ Open Diabetes Research and Care 2020:8:e001252. doi:10.1136/bmjdrc-2020-001252

By Yvelette Stines
Yvelette Stines, MS, MEd, is an author, writer, and communications specialist specializing in health and wellness.