There’s been a movement to save coffee’s bad reputation. For years, health experts considered coffee to be unhealthy.
Early studies showed coffee caused health problems. Recent studies prove that there are health benefits to drinking coffee. Why the change?
Frank Hu is the chairman of the Department of Nutrition at Harvard T.H. Chan School of Public Health.
He wrote why this might be the case. Early studies didn’t consider smoking a hazard. Smoking was probably the true cause when a subject developed heart disease.
This article discusses studies that researched the health benefits of drinking coffee.
From there, we can pinpoint how much coffee we should be drinking every day.
Benefits of Drinking Coffee
Coffee Lowers the Risk of Heart Disease
Three major studies say that coffee may play a role in lowering the risk of heart disease.
1. The Framingham Heart Study. They studied over 14,000 people from the town of Framingham, Massachusetts.
The study covered three generations of subjects. It showed a risk of heart failure dropping by 5 to 12% for each cup of coffee consumed daily.
The group that consumed no coffee showed no difference in their potential risk.
2. The Atherosclerosis Risk in Communities. This study reported that the risk of heart failure dropped by 30% in people who drank at least two cups of coffee daily. For those who consumed zero to one cup of coffee daily, there was no change in their risk.
3. The Cardiovascular Health Study. This study reported that the risk of heart failure dropped 5% to 12% per cup of coffee consumed. This was in comparison to those who had no coffee.
Those outsides of the study have pointed out two problems with the data.
The studies relied on self-reporting by the participants. And in each of these studies, the exact amount of coffee wasn’t controlled.
This means there’s no way to figure out exactly how much coffee each subject drank.
There was no difference if the participant drank decaffeinated coffee.
The conclusion is that the effects are the result of consuming caffeine. Drinking coffee itself isn’t the only way to get caffeine.
The consensus is there’s no harm in getting that caffeine by drinking coffee.
Coffee Can Lower the Risk of Type 2 Diabetes
Diabetes is a disease where there’s too much blood glucose in the bloodstream. Insulin is a hormone that’s stored in the pancreas. It’s needed to regulate glucose in the bloodstream and to convert glucose into fuel for cells.
There are two parts to type 2 diabetes.
- Insulin resistance occurs when the body has difficulty using insulin.
- Insulin deficiency occurs when the body doesn’t produce enough insulin.
In a study published in 2014, Harvard researchers looked at the diets of 100,000 people. This study took place over 20 years. Their report is significant.
Some subjects increased their intake of coffee by one cup per day. Those participants lowered their risk of developing type 2 diabetes by 11%.
Subjects that lowered their consumption by one cup a day increased their risk by 17%.
There’s no evidence that caffeine reduces the risk for diabetes. Notably, decaffeinated coffee increases a subject’s blood glucose level.
There was no discernible difference when the participants drank tea.
This suggests that drinking coffee lowers the risk of developing type 2 diabetes.
Drinking Coffee Can Reduce Body Fat
The Harvard T.H. Chan School of Public Health studied 126 non-insulin-sensitive adults.
Half of them drank four cups of coffee per day. The other half drank a placebo beverage. The study found those drinking real coffee reduced their body fat. The reported average fat loss was 4%.
This was a side note to the original study.
They attributed the loss to the fact that drinking coffee raises the metabolism.
Coffee Can Slow the Progression of Advanced Colorectal Cancer
Researchers studied 1171 patients with advanced or metastatic colorectal cancer. The study ran from October 27, 2005, to January 18, 2018. They wrote that consuming two to three cups of coffee daily slowed the progress of the disease and death.
Drinking four or more cups daily showed even greater benefits.
Researchers believe the anti-inflammatory and anti-oxidative properties of coffee contributed to the results.
It doesn’t matter if the coffee contains caffeine or not.
Drinking Coffee Can Slow the Progression of Alzheimer’s
There’s a stage of cognitive decline measured in normal aging contrasted with dementia.
This stage is Mild Cognitive Impairment or MCI. The Mayo Clinic studies this condition.
Many subjects identified as having MCI develop Alzheimer’s within a few years. This is why it’s important to track patients with this condition.
There was a study conducted in 2006.
Its goal was to see if high blood caffeine levels in patients with MCI are linked to a slower decline in dementia. Participants were from the Florida Alzheimer’s Disease Research Center (FADRC). The 124 participants ranged in age from 65 to 88 years old.
Researchers looked at subjects diagnosed with MCI and went on to develop Alzheimer’s.
Those subjects had a caffeine level in their blood 51% lower than subjects whose MCI did not progress.
The magic number of people who should reach the proper level of caffeine in their blood is 1200 ng/ml.
This is equal to drinking three cups of coffee that have an average of 95 milligrams of caffeine per cup.
How Drinking Coffee Protects the Liver
Jamile Wakim-Fleming, MD, is a liver specialist at the Cleveland Clinic. She recommends drinking at least three cups of coffee per day.
She believes coffee has components that help reduce inflammation in the liver. It does this by leveling out the enzymes needed to function without issues.
People living with chronic liver disease may see greater benefits by drinking up to six cups daily.
Those with a fatty liver or hepatitis should consider drinking up to six cups.
Drinking Coffee Reduces the Risk of the Formation of Kidney Stones
The National Kidney Foundation’s “American Journal of Kidney Diseases” published a study. They studied data from two different reports on the effects coffee has on kidney stones.
The participants were from the “FinnGen” study and the “U.K. Biobank” study. These two studies generated data from 571,657 participants with kidney stones.
Susanna C. Larsson, from the Institute of Environmental Medicine in Stockholm, was the co-author.
She wrote that drinking coffee daily lowers the risk of the formation of kidney stones. Raising the amount consumed from one cup to one and a half cups reduced the risk by as much as 40%.
Other Health Considerations When Drinking Coffee
It’s important to look at other factors before it can be determined how much coffee is needed to see health benefits.
Things to consider:
- Proper dietary guidelines.
- The threshold at which drinking coffee is excessive.
- How much caffeine is in each cup.
- What measure of liquid makes up one cup.
Several studies didn’t specify to their subjects how much liquid should be in their cup of coffee.
Also, many participants self-reported their consumption. In other words, there were no controls in place to measure exactly how much coffee each subject drank.
How Much Measured Liquid is in One Cup of Coffee
The Specialty Coffee Association says a standard cup of coffee is five ounces. The public considers 8 fluid ounces to be one cup.
The amount of coffee in a cup varies.
It is more beneficial to measure the amount of caffeine consumed.
How Much Caffeine is in a Cup of Coffee
The average cup of coffee has around 95 milligrams of caffeine. Lighter roasts have a little more caffeine.
There can also be a difference between Robusta beans and Arabica beans.
Be sure and check the package or at the roaster’s website for the amount of caffeine in one cup of coffee.
It’s important to determine the most coffee that should be consumed in a day.
Several groups need to track their caffeine intake.
They’re more susceptible to its effects than others.
Those groups include:
- Those on certain medications.
- Women who are pregnant or are breastfeeding.
- People who are more susceptible to the effects of caffeine.
People falling into one of these categories should limit their intake to less than 200 milligrams per day.
Besides heightened sensitivity, new research indicates that more is not better.
More than 17,700 participants between the ages of 37 and 73 participated in a study.
One test group drank more than six cups of coffee every day.
A second group drank one to two cups daily.
The group that drank six or more cups of coffee had smaller total brain volumes.
They also increased their risk of dementia by 53%.
This is enough to consider limiting consumption to less than six cups per day.
The general guidelines state that most women can drink three to five cups of coffee a day.
The total amount of caffeine consumed every day should not exceed 400 milligrams.
Drinking Coffee For Health Benefits
The amount of coffee to drink for health benefits mirrors DGA recommendations.
These guidelines suggest drinking three to five cups daily. The exact number of cups shouldn’t exceed 400 milligrams of caffeine.