The “healthiest” coffee will vary between drinkers. Some relevant factors include caffeine content, the brewing technique, and whether the coffee contains anything extra.
ZOE runs the largest study of nutrition science in the world and has found that coffee could be good for your gut.
Our PREDICT1 program found a strong relationship between drinking coffee and having certain beneficial bacteria in your gut.
Through our research, we know that foods and drinks that support your gut microbiome can help you achieve your best health.
You can learn more about discovering the best foods for you by taking our free quiz.
What is a healthy coffee?
The “healthiest” coffee differs from person to person. It can depend on:
how sensitive you are to the effects of caffeine
your health goals
whether you’re trying to manage anxiety or sleep disturbances
The United States Food and Drug Administration (FDA) notes that drinking 400 milligrams of caffeine a day is safe for healthy adults. That’s around 4–5 cups of coffee.
But we all process caffeine differently. While 400 mg may not make some people jittery, it can cause unwanted effects in other people.
Caffeine content aside, adding lots of sugar to coffee, either by the spoonful or in syrups and flavorings, will make it less healthy.
Factors that affect the healthiness of coffee
Here are some things that could affect your coffee’s health impact.
The extent that you roast coffee beans changes the flavor and strength of the coffee:
Light roasts have more acidity and a milder taste.
Dark roasts are more bitter and contain more caffeine.
Medium roasts are somewhere in between.
If you’re sensitive to caffeine, you might want to opt for a light or medium roast.
Lighter roasts also have higher concentrations of compounds like chlorogenic acid. These polyphenols may help protect the body against inflammation — and lower the risk of type 2 diabetes and heart disease.
There are two main types of coffee beans:
Arabica beans have a sweeter and more complex flavor profile.
Robusta beans have a stronger, more bitter taste and more caffeine.
If you’re sensitive to caffeine, it’s worth noting that Arabica beans generally have less.
Studies have found that after drying, Arabica beans contain 0.9 to 1.5% caffeine, and Robusta beans contain 1.2 to 2.4%.
Black or with milk
The effect of milk on your coffee’s health profile depends on how much you add in.
Milk can give coffee a creamy texture and a hint of sweetness. A dash of milk does this while adding a minimal amount of fat.
Coffee drinks such as lattes, which mainly consist of milk, are a source of saturated fat.
If you're watching your saturated fat intake, you may want to see these drinks as an occasional treat and be mindful of the fat in your diet throughout the day.
Milk alternatives, like soy or almond milk, can also enhance coffee’s texture without increasing your saturated fat intake.
But it’s worth noting that many milk alternatives in stores are highly processed. Many of the beneficial parts of the plants break down during the manufacturing process.
Plant milks also typically lack the protein and calcium in dairy milk and contain extra ingredients with little or no nutritional value.
But overall, adding only a small amount of milk doesn't significantly change how healthy your coffee is for you.
There are various ways to brew coffee — including espresso, filter, French press, and AeroPress. Each method gives the drink a different flavor and strength.
One study compared the effects of different brewing techniques at a coffee shop on coffee’s antioxidant content.
Antioxidants can help repair and prevent damage to your cells and genetic material.
The researchers looked at the four techniques we mention above. Coffee from a French press or espresso machine had the lowest levels of antioxidants, while AeroPress coffee had the highest.
Still, the authors of the study concluded that the overall antioxidant levels were still “very high,” even after accounting for the brewing method.
The size of your coffee can affect how much caffeine you get and the flavor's strength.
A smaller serving size generally means less caffeine and a milder taste. So, if you're sensitive to caffeine or trying to cut back, a smaller coffee might be healthier for you.
Additions beyond milk
Having flavorings in your coffee can improve the taste, but it also tends to add sugar and saturated fat.
Cutting back on these extras can help make your coffee more healthy for you.
If you're watching your sugar intake but still want a sweet treat, you might opt for sugar alternatives, like honey or stevia. But these either contain sugar or lack research into their long-term effects.
Hot or cold brew
People make cold brew coffee by steeping coffee grounds in cold water for several hours. This can result in a smoother flavor.
But research has found that hot brewing coffee may extract more acids from the bean and increase polyphenol activity.
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General health benefits of coffee
Coffee boasts plenty of health benefits beyond a caffeine boost.
ZOE’s research, which we touched on earlier, found that coffee may support the range of beneficial bugs living in your gut.
“We saw a very strong correlation between drinking coffee and the composition of the gut microbiome,” says Prof. Nicola Segata, one of the study’s authors. “We noticed that people who drank coffee tended to have higher microbiome diversity.”
Researchers often agree that the more diverse your gut microbiome is, the healthier it is.
ZOE’s personalized nutrition program can tell you which “good” and “bad” bugs live in your gut. Take our quiz to learn how it works.
Meanwhile, other research hints that coffee might support your health in different ways. For example:
There are promising signs that caffeine may benefit cognition, though scientists need to do more research.
Research in rats suggests that other compounds in coffee may also help improve your long-term cognitive function and memory.
Some observational studies have spotted possible links between drinking coffee and having a lower risk of heart disease, diabetes, and stroke.
These effects might stem from coffee reducing inflammation throughout your body. Long-term, uncontrolled inflammation has links to chronic conditions, like type 2 diabetes and heart disease.
Polyphenols in coffee, such as chlorogenic acid, may reduce cell damage and help repair cells.
Coffee may help people who are managing their weight maintain long-term weight loss. Drinking more caffeine has possible links to lower body mass index, body weight, and overall fat mass. But remember to be mindful about what you add to it.
Drinking coffee every day is associated with a higher likelihood of exercising, according to the results of one study.
If you’d like to dig deeper, you can find our article on coffee’s health benefits here or watch the video of our podcast on coffee below.
What about decaf?
Decaffeinated coffee has similar potential health benefits to regular coffee. They contain the same plant compounds and fiber.
Still, most research into coffee has either looked at caffeinated coffee alone or failed to distinguish between the two types.
Special types of coffee
Some places sell coffee with ingredients aimed to provide an extra health kick. But there’s been very little research to confirm any of these purported health benefits.
This coffee, of course, contains turmeric, a spice known for its anti-inflammatory and antioxidant properties.
Some claim that the drink helps improve digestion, boost immune function, and even relieve depression.
Research has demonstrated that turmeric itself can benefit our health. But we still lack research into turmeric coffee. It’s unclear whether it will help.
Bulletproof coffee combines coffee, unsalted butter, and medium-chain triglyceride oil. Some followers of the keto diet drink it because it's high in fat and low in carbs.
Fans claim that the drink provides sustained energy, increased focus, and weight loss benefits.
A small 2021 study found no evidence of cognitive benefits but suggested that the fat content increased feelings of fullness and reduced snacking between meals.
Overall, there’s limited research on bulletproof coffee. And the high saturated fat content may have unfavorable health effects for some people.
Egg coffee is a traditional Vietnamese brew with egg yolks and condensed milk. Its creamy richness comes from the yolks being whipped into the milk.
Some people say that egg coffee provides a protein boost and can help with digestion, but no scientific evidence currently supports this.
Some coffee contains an infusion of medicinal mushrooms, like chaga or Cordyceps. People claim that mushroom coffee can boost energy, improve mental clarity, and support the immune system.
A 2020 study looked at coffee containing Cordyceps, chaga, and Phellinus mushrooms.
The researchers found that the drink had higher levels of antioxidants called polyphenols than raw mushrooms, but only slightly higher levels than regular coffee.
The amount of beta-glucans, a type of fiber than can help with blood sugar control, was lower in the mushroom coffee than in the mushrooms.
While people have eaten mushrooms medicinally for centuries, there’s limited research on their health benefits in coffee.
This drink contains nootropic compounds, substances that may enhance cognitive function.
Nootropics include L-theanine, taurine, and choline. The producers of some specialty coffees use these as ingredients.
Supporters of nootropic coffee say that it can improve focus, memory, and mental clarity. However, there’s limited relevant research.
This coffee has a cannabidiol (CBD) infusion. CBD is a non-psychoactive compound in cannabis. It may have various health benefits, including reducing anxiety, improving sleep, and relieving pain.
While cannabis compounds might help treat chronic pain, anxiety, nausea from chemotherapy, epilepsy, and appetite loss in people with HIV, there’s limited research on CBD coffee.
It's also important to note that the legal status of CBD varies by location.
The healthiest coffee for you depends on your nutritional needs, health goals, and caffeine sensitivity.
If you don’t experience unwanted effects, like jitteriness, all coffee is pretty healthy before things like cream and syrup enter the picture.
Overall, lighter roasts generally have less caffeine and more antioxidants than darker roasts. The type of bean can affect the caffeine content, but both Arabica and Robusta beans can give you the full health benefits of coffee.
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