Coffee is one of the most popular beverages today, and millions of people start their day with a warm cup of java.
People drink it for its taste, flavor, out of habit or truly rely on it for energy. Well, the reasons can be many. Some even drink for health reasons.
Coffee comes from a bean, so it contains phytonutrients and polyphenols, chemical compounds that are believed to have antioxidant benefits. It also has caffeine, riboflavin (vitamin B2), pantothenic acid (vitamin B5), manganese, potassium, magnesium and niacin.
When taken in moderation, coffee provides many benefits. It can improve liver health, stimulate adrenaline to make you more alert, fight free radicals, boost your mood, lower your risk of heart disease and much more.
But when you become addicted to coffee and find it difficult to go a day without it, you may be drinking excess amounts that can cause several potential health problems.
Here are the top 10 side effects of excess coffee intake.
1. Increases Cholesterol Levels
Coffee, particularly when unfiltered, may increase total cholesterol and low-density lipoprotein (LDL or ‘bad’ cholesterol) levels. Unfiltered coffee contains two cholesterol-raising substances, known as cafestol and kahweol.
In a 2001 study published in the American Journal of Epidemiology, researchers found that consumption of unfiltered, but not filtered, coffee increases serum levels of total and LDL cholesterol.
Another study published in 2007 in Molecular Endocrinology reports that cafestol elevates cholesterol by hijacking a receptor in an intestinal pathway critical to its regulation. In fact, cafestol is the most potent dietary cholesterol-elevating agent known.
If you have high cholesterol, limit or avoid unfiltered coffee and opt for filtered versions instead.
2. Causes Insomnia
If you drink your coffee later in the day, it can actually lead to insomnia or make it worse if you already have it.
Drinking coffee later in the afternoon or too close to bedtime can keep anyone up. The caffeine in coffee works as a stimulant and can result in increased alertness, cause nervousness and dizziness, and ultimately cause sleep disturbance and insomnia.
Plus, caffeine can interfere with normal REM sleep and make you feel exhausted.
A 2013 study published in the Journal of Clinical Sleep Medicine reports that having caffeine six hours before bedtime affects sleep. The study sheds light on the importance of refraining from substantial caffeine use for a minimum of six hours prior to bedtime.
Stop having coffee (and all other caffeine consumption) after mid-afternoon if you think it may be impacting your ability to sleep well at night.
3. Increases Anxiety and Panic Attacks
Caffeine can help make you more alert and focused, but high intake can impact your mood and cause anxiety and panic attacks.
When you drink coffee in excess, this can create dependence, resulting in withdrawal symptoms when you go without it. This can cause jitteriness and nervousness and increase anxiety and panic attacks.
A 2005 study published in Advances in Psychiatric Treatment found that caffeine increased anxiety, hostility and psychotic symptoms in psychiatric inpatients. The study emphasizes that assessment of caffeine intake should be a part of routine psychiatric assessments and should be carried out before prescribing medicines.
If you tend to become overstimulated after drinking coffee, then cut back or consider eliminating it completely from your daily diet.
4. Damages Kidneys
Being diuretic in nature, coffee stimulates the kidneys to excrete more fluid, making you urinate more often.
The caffeine interferes with the way fluid is reabsorbed into the blood, which is not a problem for those who have normal kidney function.
However, long-term consumption of coffee can affect your kidneys.
A 2002 study published in Kidney International reports that long-term caffeine intake can cause chronic kidney failure in obese and diabetic rats.
The oxalates in coffee are compounds that bind with calcium in the blood to create calcium oxalate, which is a major component of kidney stones. A 2004 study published in the Journal of Urology reports that caffeine intake may modestly increase risk of calcium-oxalate stone formation.
Coffee in moderate amounts will not cause any problem to your kidneys. Hence, drink no more than 1 to 2 cups of coffee per day.
5. Weakens Bones
Too much coffee consumption is also bad for your bone health. In fact, it raises your risk of developing brittle bones or osteoporosis.
Excess caffeine may interfere with absorption and metabolism of calcium, which in turn contributes to bone thinning (osteoporosis).
A 2001 study published in the American Journal of Clinical Nutrition reports that caffeine intake increases the rate of bone loss in elderly women and interacts with vitamin D receptor genotypes.
Another study published in 2006 in Osteoporosis International found that a daily intake of 4 or more cups of coffee may cause increased risk of osteoporotic fractures, especially in women with low calcium intake.
Do not drink more than 2 cups of coffee a day and also limit your intake of other kinds of caffeinated beverages.
6. Stains Your Teeth
If you drink a lot of black coffee, beware of the fact that it can stain your teeth.
The tooth enamel contains microscopic pits and ridges that can hold particles of food and beverages. The pigments from dark-colored drinks like coffee can become embedded in those pits and ridges and ultimately lead to yellow stains on your teeth.
Not just black, even white coffee will stain teeth but it is less concentrated, so the effect is less.
Rather than quitting coffee completely, just drink it in moderation. Also, after finishing your coffee, make sure to rinse your mouth with water or brush your teeth to remove the harmful pigments from your teeth.
7. Raises Blood Pressure and Heart Rate
Drinking large amounts of coffee can lead to an increase in blood pressure and heart rate, due to the caffeine’s impact on hormones and neurotransmitters.
A 2011 study published in the American Journal of Clinical Nutrition reports that caffeine intake in hypertensive individuals produces an acute increase in blood pressure for around three hours. However, current evidence did not shed light on long-term coffee consumption and increased blood pressure or habitual coffee consumption and an increased risk of cardiovascular disease in hypertensive subjects.
A 2014 study published in the International Journal of Scientific and Research Publications reports that the multiple effects of caffeine, such as being an adenosine receptor blocker and increasing levels of angiotensin II and catecholamines, leads to an increase in heart rate and blood pressure. In fact, caffeine increased systolic blood pressure as much as 17 percent and mean arterial blood pressure by about 11 percent.
As drinking coffee in moderation does not have a noticeable impact on healthy adults, you can enjoy your java but in limited amounts.
8. Causes Heartburn Problems
Acid reflux and heartburn can be caused by excess coffee consumption.
Coffee reduces pressure in the lower esophageal sphincter, contributing to gastroesophageal reflux. This in turn can either cause or exacerbate heartburn in susceptible individuals.
In normal conditions, the small muscles in the lower esophageal sphincter remain tightly closed after you’ve eaten to prevent your stomach contents from coming back into the esophagus and burning the lining with hydrochloric acid.
Also, coffee tends to speed up the process of gastric emptying, which may lead to highly acidic stomach contents passing into the small intestine more rapidly than normal.
If you have stomach problems like heartburn or acid reflux, it’s best to quit drinking coffee completely.
9. Gives You Bad Breath
Just 1 to 2 cups of coffee a day cannot cause bad breath, but if taken in excess, it can give you bad breath.
Heavy coffee drinking can dry out your mouth, due to its dehydrating nature. As the mucosal cells that line the inside of the mouth become dry, less saliva is produced.
Saliva helps kill bacteria found in your mouth and helps you digest food particles. Without enough saliva, the bacteria that cause bad breath will grow out of control.
Plus, coffee has sulfurous content, which certain bad breath-causing bacteria can break down to produce odor.
Drinking water with coffee or chewing sugar-free gum after coffee can help prevent bad breath.
10. Affects Unborn Babies
High amount of coffee intake during pregnancy is something every pregnant woman should avoid. Its high caffeine content works as a stimulant that can affect your baby’s heart rate.
Caffeine also raises the risk of miscarriage or of a baby being born with a low birth weight.
As caffeine increases your heart rate and metabolism, and makes you feel more alert, it can similarly affect your unborn baby. This means the unborn baby may become a bit unsettled after you’ve had a cup of coffee.
In addition, excess caffeine can cause dehydration, which is again not good for the unborn baby.
Drinking 2 cups of instant coffee or 1 cup of filtered coffee a day is fine during pregnancy but not more than that.