Drinking Coffee Can Improve Energy Levels and Make You Smarter
Coffee can help people feel less tired and increase energy levels because it contains a stimulant called caffeine — the most commonly consumed psychoactive substance in the world. (1, 2).
After you drink coffee, the caffeine is absorbed into your bloodstream. From there, it travels to your brain. (3).
In the brain, caffeine blocks the inhibitory neurotransmitter adenosine.
When this happens, the amount of other neurotransmitters like norepinephrine and dopamine increases, leading to enhanced firing of neurons. (4, 5).
Many controlled studies in humans show that coffee improves various aspects of brain function — including memory, mood, vigilance, energy levels, reaction times and general mental function. (6, 7, 8).
Drinking Coffee Can Help You Burn Fat
Caffeine is found in almost every commercial fat-burning supplement — and for good reason. It’s one of the few natural substances proven to aid fat burning.
Several studies show that caffeine can boost your metabolic rate by 3–11%. (9, 10).
Other studies indicate that caffeine can specifically increase fat burning by as much as 10% in obese individuals and 29% in lean people. (11).
Drinking Coffee Can Drastically Improve Physical Performance
Caffeine stimulates your nervous system, signalling fat cells to break down body fat. (12, 13).
But it also increases epinephrine (adrenaline) levels in your blood. (14, 15).
This is the fight-or-flight hormone, which prepares your body for intense physical exertion.
Caffeine breaks down body fat, making free fatty acids available as fuel. (16, 17).
Given these effects, it’s unsurprising that caffeine can improve physical performance by 11–12%, on average. (18, 19).
Therefore, it makes sense to have a strong cup of coffee about half an hour before you head to the gym.
Coffee Contains Essential Nutrients
Many of the nutrients in coffee beans make their way into the finished brewed coffee.
A single cup of coffee contains (20):
Riboflavin (vitamin B2): 11% of the Reference Daily Intake (RDI).
Pantothenic acid (vitamin B5): 6% of the RDI.
Manganese and potassium: 3% of the RDI.
Magnesium and niacin (vitamin B3): 2% of the RDI.
Though this may not seem like a big deal, most people enjoy several cups per day — allowing these amounts to quickly add up.
Drinking Coffee May Lower Your Risk of Type 2 Diabetes
Type 2 diabetes is a major health problem, currently affecting millions of people worldwide.
It’s characterised by elevated blood sugar levels caused by insulin resistance or a reduced ability to secrete insulin.
For some reason, coffee drinkers have a significantly reduced risk of type 2 diabetes.
Studies observe that people who drink the most coffee have a 23–50% lower risk of getting this disease. One study showed a reduction as high as 67%. (21, 22, 23, 24, 25).
According to a large review of 18 studies in a total of 457,922 people, each daily cup of coffee was associated with a 7% reduced risk of type 2 diabetes. (26).
Drinking Coffee May Protect You From Alzheimer's Disease and Dementia
Alzheimer's disease is the most common neurodegenerative disease and the leading cause of dementia worldwide.
This condition usually affects people over 65, and there is no known cure.
However, there are several things you can do to prevent the disease from occurring in the first place.
This includes the usual suspects like eating healthy and exercising, but drinking coffee may be incredibly effective as well.
Several studies show that coffee drinkers have up to a 65% lower risk of Alzheimer's disease. (27, 28).
Drinking Coffee May Lower Your Risk of Parkinson's
Parkinson's disease is the second most common neurodegenerative condition, right behind Alzheimer's.
It’s caused by the death of dopamine-generating neurons in your brain.
As with Alzheimer's, there is no known cure, which makes it that much more important to focus on prevention.
Studies show that coffee drinkers have a much lower risk of Parkinson's disease, with a risk reduction ranging from 32–60%. (29, 30, 31, 32).
In this case, the caffeine itself appears to be beneficial, as people who drink decaf don't have a lower risk of Parkinson's. (33).
Drinking Coffee May Protect Your Liver
Your liver is an amazing organ that carries out hundreds of important functions.
Several common diseases primarily affect the liver, including hepatitis, fatty liver disease and many others.
Many of these conditions can lead to cirrhosis, in which your liver is largely replaced by scar tissue.
Interestingly, coffee may protect against cirrhosis — people who drink 4 or more cups per day have up to an 80% lower risk. (34, 35, 36).
Drinking Coffee Can Fight Depression and Make You Happier
Depression is a serious mental disorder that causes a significantly reduced quality of life.
It’s very common, as about 4.1% of people in the US currently meet the criteria for clinical depression.
In a Harvard study published in 2011, women who drank 4 or more cups of coffee per day had a 20% lower risk of becoming depressed. (37).
Another study in 208,424 individuals found that those who drank 4 or more cups per day were 53% less likely to die by suicide. (38).
Drinking Coffee May Lower Risk of Certain Types of Cancer
Cancer is one of the world's leading causes of death. It is characterised by uncontrolled cell growth in your body.
Coffee appears to be protective against two types of cancer: liver and colorectal cancer.
Liver cancer is the third leading cause of cancer death in the world, while colorectal cancer ranks fourth. (39).
Studies show that coffee drinkers have up to a 40% lower risk of liver cancer. (40, 41).
Similarly, one study in 489,706 people found that those who drank 4–5 cups of coffee per day had a 15% lower risk of colorectal cancer. (42).