Negative effects of coffee: The ups & downs of caffeine
How you react to caffeine may be determined in part by how much caffeine you’re used to drinking. People who don’t regularly drink caffeine tend to be more sensitive to its negative effects. However, some people are just more sensitive to caffeine than others. If you’re susceptible to the effects of caffeine, just small amounts – even one cup of coffee or tea – may prompt unwanted effects, such as restlessness and sleep problems. Drink a lot of coffee and you may head to the bathroom more often. Caffeine is a mild diuretic – that is, it makes you urinate more than you would without it. Decaffeinated coffee has about the same effect on urine production as water.
Other factors may include body mass, age, medication use and health conditions such as anxiety disorders. Research also suggests that men may be more susceptible to the effects of caffeine than are women.
Most specialists and experts will say the recommended maximum amount of caffeine is 400 milligrams, approximately 4 cups of coffee. If you’re caffeine-sensitive, be careful with coffee. You are probably already aware what amount and what kind of coffee suits, or doesn’t suit you.
The amount of caffeine that is safe for human consumption is actually written in our DNA. Listen to your body and how it reacts.
Be cautious with caffeine consumption…
If you have health concerns
Adults as well as children with either diagnosed or undiagnosed medical conditions can have adverse health implications with even small amounts of caffeine. For those with certain health conditions, giving up caffeine may be recommended. Here are some conditions that usually warrant quitting caffeine or caution consuming the drug.
If you have heart conditions
Because caffeine is a stimulant, it increases heart rate as well as blood pressure. Therefore, those with heart arrhythmias³, murmurs, and hypertension should limit their caffeine intake.
Those with pre-existing arrhythmias, murmurs, and hypertension should limit caffeine to no more than 200mg daily and are advised to consult their physician before consuming caffeine.
If you have Type 2 Diabetes
The majority of the research shows that caffeine doesn’t increase the risk of someone developing type 2 diabetes, but actually decreases risk.
However, those already diagnosed with type 2 diabetes should limit caffeine consumption because it can impair glucose metabolism in diabetics.
Those with type 2 diabetes should restrict their consumption to around 200mg daily or follow their doctor’s instructions concerning caffeine intake.
If you are pregnant or nursing
There are several studies that have shown evidence for increased risk of miscarriage or early stillbirth delivery among pregnant women who consumed more than moderate amounts of caffeine (read more here).
Mothers consuming 200mg (2 cups) of caffeine or less a day results in very little risk for the developing fetus and nursing infant.
If you’re not getting enough sleep
Most adults need seven to eight hours of sleep each night. But caffeine can interfere with this much-needed sleep. Chronically losing sleep — whether it’s from work, travel, stress or too much caffeine — results in sleep deprivation. Sleep loss is cumulative, and even small nightly decreases can add up and disturb your daytime alertness and performance.
Using caffeine to mask sleep deprivation can create an unwelcome cycle. For example, you may drink caffeinated beverages because you have trouble staying awake during the day. But the caffeine keeps you from falling asleep at night, shortening the length of time you sleep.
So how much is too much?
Up to 400 milligrams (mg) of caffeine a day (4 cups) appears to be safe for most healthy adults. That’s roughly the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two “energy shot” drinks.
Although caffeine use may be safe for adults, it’s not a good idea for children. And adolescents should limit themselves to no more than 100 mg of caffeine a day.
Even among adults, heavy caffeine use can cause unpleasant side effects. And caffeine may not be a good choice for people who are highly sensitive to its effects or who take certain medications.
It’s difficult to assign an exact amount for everyone because people can have different sensitivities or reactions to caffeine based on age, medical history, and tolerance.
However, there is enough research available to make a recommendation based on an individual’s weight.
Heavy daily caffeine use (more than 500mg – 600mg p/day) or sensitivity to caffeine may cause side effects such as:
- Stomach upset
- Fast heartbeat
- Muscle tremors
So, should you be drinking coffee?
This depends on your current health, lifestyle and sensitivity to caffeine. Listen to your body. If you have any of the above side effects, perhaps switch to herbal tea or decaffeinated coffee.
If there are concerns about particular health aspects, you should consult your doctor.
For others, reasonable amounts (1-4 cups a day) coffee can be good for you. It can prevent serious diseases, boost your mind and muscles, and even help you with weight loss. Remember, as long as you drink toxin free, specialty coffee and brew it with care, you can and should be enjoying it knowing it’s good for you.
Read more on the importance of keeping health over 60 in volume 2.
Volume two: Looking after your health and well-being after 60
– WebMD, Coffee and Your Health. Osterweil, N. Read article
– Caffeineinformer. Caffeine During Pregnancy: How Much is Safe? Read article
– caffeineinformer, Caffeine Safe Limits: Determine Your Safe Daily Dose. Read article
– Mayo Clinic, Caffeine: How much is too much? April 14, 2014. Read article
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