Coffee Consumption, Genetics, and Prediabetes

Does coffee increase or decrease your risk of prediabetes? What if you add sugar to your morning cup o’ joe? Do your genes matter here?

A study that included almost 8,000 people in South Korea sought to answer this question.[ref]

Coffee, genes, and diabetes:

The study looked at the incidence of either type 2 diabetes or prediabetes in the participants over the course of 12 years. Researchers found that almost 12% of the participants were diagnosed with diabetes and over 60% became prediabetic during that time.

Overall, consuming 2 or more cups of coffee each day decreased the risk of diabetes or prediabetes.

Surprisingly, even drinking sugar-sweetened coffee reduced that risk of diabetes/prediabetes, but the risk reduction was not quite as much as in the black coffee group.

What is interesting, though, is that the decrease in risk varied quite a bit, depending on which genetic variants a person carried. Some people had a 13% risk reduction while others had up to a 64% risk reduction.

The researchers used a genetic risk score based on 5 genetic variants (SNPs). The people with a higher number of variant alleles had the greatest decrease in the risk of diabetes

Genetic variants to check:

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Interested in how your genetic risk stacks up? Three of the five variants are available in 23andMe or AncestryDNA data.

The researchers found that these variants didn’t have statistical significance on their own, but added together, the variants made a difference.

C12orf51 gene: 

Check your genetic data for rs2074356 (23andMe v4, v5)

  • G/G: typical
  • G/A: adds to the decrease in diabetes risk for coffee drinkers
  • A/A: adds to the decrease in diabetes risk for coffee drinkers[ref]

Members: Your genotype for rs2074356 is .

ACAD10 gene: part of the acyl-CoA dehydrogenase family of genes that is important in beta-oxidation in the mitochondria. This is the same gene that is important in impaired lipid metabolism in Pima indians.

Check your genetic data for rs11066015 (23andMe v5; AncestryDNA )

  • G/G: typical
  • G/A: adds to the decrease in diabetes risk for coffee drinkers
  • A/A: adds to the decrease in diabetes risk for coffee drinkers[ref]

Members: Your genotype for rs11066015 is .

MYL2 gene: encodes a protein that regulates the expression of skeletal and cardia muscle myosin.

Check your genetic data for rs12229654 (23andMe v5; AncestryDNA)

  • T/T: typical
  • G/T: adds to the decrease in diabetes risk for coffee drinkers
  • G/G: adds to the decrease in diabetes risk for coffee drinkers[ref]

Members: Your genotype for rs12229654 is .

Additionally, two more variants also impacted the decreased risk score: rs11065828 (A allele) and rs79105258 (A allele)

Keep in mind that this study was conducted on people with an Asian genetic background. It hasn’t been replicated yet in other population groups.


Caffeine vs polyphenols in coffee:

Is it the caffeine in the coffee that decreases diabetes risk? A meta-analysis that combined information for over 1,000,000 study participants found that both decaffeinated and regular coffee decreased the risk of type 2 diabetes. The greater the number of cups of coffee correlated to a greater decrease in diabetes risk.[ref]

The main polyphenol in coffee is chlorogenic acid, which inhibits glucose-5-phosphatase production in the liver. This may cause decreased glucose output by the liver, thus reducing blood glucose levels.[ref][ref]

Other ways to decrease blood glucose levels:

There are many ways that you can work towards lowering your blood glucose levels and preventing or reversing prediabetes. Coffee is just one possibility. If you are interested in how your genes influence blood glucose levels, check out these articles:

Hate coffee? You may want to check out your taste receptor genes. Some people can detect the bitter flavors in coffee much more strongly than others.

Related Articles and Genes:

Coffee: Is it right for your genes?
Coffee — is it good or bad for you? Coffee is one of the most popular drinks in the world, second only to tea. It is sometimes controversial due to its caffeine content.

CYP1A2 – Breaking down caffeine and more
The CYP450 family of enzymes is responsible for breaking down and getting rid of all the various toxins that we come in contact with on a daily basis. CYP1A2, a part of the CYP450 family, is of interest to many due to its impact on caffeine.


Top 10 Genes to Check in Your Genetic Raw Data
Wondering what is actually important in your genetic data? These 10 genes have important variants with a big impact on health. Check your genes (free article).

Author Information:   Debbie Moon
Debbie Moon is the founder of Genetic Lifehacks. She holds a Master of Science in Biological Sciences from Clemson University and an undergraduate degree in engineering from Colorado School of Mines. Debbie is a science communicator who is passionate about explaining evidence-based health information. Her goal with Genetic Lifehacks is to bridge the gap between the research hidden in scientific journals and everyone's ability to use that information. To contact Debbie, visit the contact page.