Love Coffee, or Hate It? The Answer’s in Your Genes

Your metabolism may be fast — or slow
Love Coffee or Hate It? The Answer's in Your Genes

Can’t do without your daily espresso or can’t do coffee, period? The answer may lie in your genes.

Advertising Policy

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

A gene called CYP1A2 controls how fast you break down caffeine. If both your parents pass down the “fast” form of the gene, your liver clears caffeine from the body fast. But if one or both parents pass on the “slow” form, your liver takes four times longer to process it.

“If you drink a normal, filtered 8-ounce cup of coffee and, within an hour, you don’t get a headache, you don’t get abnormal heart beats, you don’t get anxiety, you don’t get gastric upset, then you’re most likely a fast metabolizer and will get a benefit,” says Michael Roizen, MD.

What a difference a gene makes

  • Focused vs. frantic. Drinking two to three cups of brewed coffee give fast metabolizers a calm sense of heightened focus. In contrast, just one cup can make slow metabolizers jittery or nervous, or trigger a headache or palpitations.
  • Heart-friendly or not? Coffee has heart-healthy plant nutrients, and caffeine helps open blood vessels. While drinking one to three cups a day decreases heart attack risk for fast metabolizers, it increases risk for slow metabolizers. Drinking coffee also lowers hypertension risks for fast metabolizers but raises them for slow metabolizers.
  • The competitive edge. That caffeine boosts athletic performance is well-known. But fast metabolizers experience a higher increase in muscle endurance. In a study of male cyclists, caffeine pills improved fast metabolizers’ time by 4.9 percent and slow metabolizers’ time by just 1.8 percent.

Coffee’s overall benefits

“For the over 80 percent of Americans who are fast metabolizers, the benefits of coffee generally outweigh the risks,” says Dr. Roizen.

Advertising Policy

To start with, coffee keeps you regular. Once coffee reaches your stomach, it stimulates gastric acid to break down proteins in food. Then it boosts hormones that set your digestion in motion.

Some studies suggest that drinking coffee also reduces risks of type 2 diabetes, many cancers, Alzheimer’s disease and Parkinson’s disease. But there is some conflicting data, so research to confirm these benefits continues.

Tips on making coffee

If you love your coffee, follow these tips to reap its benefits:

Advertising Policy
  • Always filter your coffee. Unfiltered coffee will wake you up in the morning but can raise your cholesterol. “You need to filter out the substance that raises ‘lousy’ LDL cholesterol levels,” says Dr. Roizen. “Whether you use a paper towel, or a napkin, or a formal filter, it’s got to be paper.”
  • Rethink sweeteners. Added sweeteners and flavorings can push you over your daily sugar intake limit (6 teaspoons for women, 9 for men). Too much sugar increases your risks of type 2 diabetes and heart disease.

Also, a word of caution: If you have certain medical conditions like acid reflux, urinary or bladder problems, or gallstones, coffee may cause problems.

Advertising Policy