Coffee: The White, the Brown and the Black

–

Dr. Divya Samat

Intern,

K.J. Somaiya Hospital, Mumbai

As the cup reaches my mouth and the elixir glides down my throat, a sigh of relief and appreciation escapes my lips as I feel the threat of an impending headache dissipate. This is perfection in a mug-steaming hot, smooth and perfectly brewed. With each sip, it whispers its promises to carry me through another busy day on its beautiful brown angel wings. The caffeine recharges me, bridging the difference between the hours of sleep I managed to get last night and the energy I need to make it through this shift. I feel my eyes open wider, the gleam returning as I sip the last of my coffee and walk towards my first patient of the day, a spring in my step.

Through the years, coffee has been the subject of much debate with arguments being made for its harmful, potentially carcinogenic substance or likening its addictive potential to that of drugs. In 1991, coffee was included in a list of possible carcinogens by the World Health Organization. By 2016, it was exonerated, as research found that the beverage was not associated with an increased risk of cancer; on the contrary, there was a decreased risk of certain cancers among those who drink coffee regularly once the smoking history was properly accounted for. Additional accumulating research suggests that when consumed in moderation, coffee can almost be considered a ‘healthy’ beverage. Although the debate surrounding coffee and its possible merits and demerits can be complicated and often confusing, one thing has stayed constant through the years-the universal love for coffee.

If you’re an ardent coffee lover, as I consider myself to be, I’m sure you might have heard at least some of these remarks. Be it an Indian grandmother blaming ‘dark complexion’ on black coffee consumption, or a neighbourhood aunty warning that drinking coffee can cause stomach cancer (verified by Whatsapp University of course) or a concerned peer wondering out loud about the addictive nature of caffeine and the withdrawal symptoms of the same. Well, lucky for you, I am here to give you the latest research backing the health benefits of coffee and debunk at least some of those myths. 

So how many cups of coffee should one consume per day?

According to the Dietary Guidelines for Americans, it’s safe for most people to drink three to five cups of coffee a day with a maximum intake of 400 milligrams of caffeine. Caffeine content can vary depending on the type of coffee, but an average 8-ounce cup has 95 milligrams.

What are some of the health benefits of drinking coffee?

Well, for starters, you could live longer.

Recent studies found that coffee drinkers are less likely to die from some of the leading causes of death such as diabetes, coronary heart disease, stroke, etc

In a meta-analysis of 21 prospective studies of men and women looking at coffee consumption and death from chronic diseases, a link was found between moderate coffee consumption (3 cups per day) and a 21% lower risk of cardiovascular disease deaths compared with non-drinkers.

• Decreased risk of Type 2 Diabetes

Although ingestion of caffeine can increase blood sugar in the short-term, long-term studies have shown that habitual coffee drinkers have a lower risk of developing type 2 diabetes compared with non-drinkers.

In fact, one review of 30 studies found that each cup of coffee people consumed per day was linked to a 6% lower risk of developing type 2 diabetes.

There was found to be a 30% decreased risk of type 2 diabetes in those drinking the highest amounts of coffee and caffeine and a 20% decreased risk when drinking decaffeinated coffee

This is thought to be due to coffee’s ability to preserve the function of the beta cells in your pancreas, which are responsible for producing insulin to regulate blood sugar levels.

The antioxidants, polyphenols and minerals such as magnesium in coffee may improve the effectiveness of insulin and glucose metabolism in the body and decrease inflammation.

• Decreased likelihood of developing heart failure.
  Drinking one to two cups of coffee a day may help delay heart failure, when a weakened heart has difficulty pumping enough blood to the body.

However, keep in mind that caffeine could affect blood pressure levels. Therefore, people with unmanaged blood pressure may need to limit or moderate their caffeine intake

• Protective against certain cancers

1 in 23 women develop colon cancer, but researchers found that coffee drinkers were 26% less likely to develop colorectal cancer.

Dark roast coffee decreases breakage in DNA strands, which can lead to cancer or tumours if not repaired by your cells.

Coffee may affect how cancer develops, ranging from mitigating the effects of carcinogens to interfering with the spread of cancer cells. For example, coffee may stimulate the production of bile acids and speed digestion through the colon, which can lower the amount of carcinogens to which colon tissue is exposed.

Various polyphenols in coffee have been shown to prevent cancer cell growth in animal studies.

Caffeine itself may interfere with the growth and spread of cancer cells.

Coffee also appears to lower inflammation, a risk factor for many cancers.

Coffee has also been associated with decreased oestrogen levels, a hormone linked to several types of cancer.

• Decreased risk of stroke

For women, drinking at least one cup of coffee a day is associated with lowered stroke risk, which is the fourth leading cause of death in women.

Among 83,076 women in the Nurses’ Health Study, drinking 4 or more cups of coffee each day was associated with a 20% lower risk of stroke compared with non-drinkers. Decaffeinated coffee also showed an association, with 2 or more cups daily and a 11% lower stroke risk.

• Doing away with the Monday Blues

Caffeine may affect mental states such as increasing alertness and attention, reducing anxiety, and improving mood.

A moderate caffeine intake of less than 6 cups of coffee per day has been associated with a lower risk of depression and suicide.

• Boosting Energy Levels

Coffee contains caffeine, a central nervous system stimulant. Caffeine blocks the receptors of a neurotransmitter called adenosine, and this increases levels of other neurotransmitters in your brain that regulate your energy levels, including dopamine.

.

• May promote weight management

According to some research, coffee could alter fat storage and support gut health, both of which may be beneficial for weight management.

Furthermore, one study found that people who drank one to two cups of coffee per day were 17% more likely to meet recommended physical activity levels, compared with those who drank less than one cup per day. These higher levels of physical activity could help promote weight management as well.

• Decreased chances and slower progression of Parkinson’s disease.
  Caffeine is not only linked to a lower chance of developing Parkinson’s disease, but it may also help those with the condition better control their movements.

People who regularly consumed caffeine were found to have a significantly lower risk of developing Parkinson’s disease. What’s more, caffeine consumption also slowed the progression of Parkinson’s disease over time.

Additionally, several studies have demonstrated that moderate coffee consumption could be associated with a lower risk of dementia and cognitive decline

This all sounds good but, what’s the catch?

How is it that some people can consume 3-4 cups of coffee and sleep peacefully at night while a single cup of coffee might keep another person on edge throughout the day?

Human response to coffee or caffeine can also vary substantially across individuals due to a complex relationship between genes and caffeine metabolism and how different populations have evolved to tolerate more or less caffeine.

Low to moderate doses of caffeine (50–300 mg) may cause increased alertness, energy, and ability to concentrate, while higher doses may have negative effects such as anxiety, restlessness, insomnia, and increased heart rate.

While coffee consumption may impart a number of health benefits over time, certain groups such as pregnant women and children should approach consumption carefully. Additionally caffeine consumption may cause anxiety and other untoward effects in susceptible populations such as those with diagnosed anxiety and panic disorders.

Is it correct to refer to coffee as a drug?

Coffee is in a somewhat unusual position. On one hand, it has clearly defined withdrawal symptoms, like headache, fatigue, trouble concentrating, and can lead to tolerance and cravings. On the other hand, other hallmarks of substance abuse and dependence, like absence from important social or work situations, use in physically dangerous situations or legal issues are absent.  However, to equate caffeine dependence with more serious substance use issues would serve to minimise them. While the consequences that come with any habit-forming substance shouldn’t be discounted, experts say that people generally tend to successfully moderate caffeine use by drinking less coffee when they experience negative effects.

In conclusion, tertiary education often requires students to study for extended hours, especially prior to examinations. Medical students, who have to master a very large volume of academic work in a limited period of time, are no exception. In these circumstances, coffee serves as the crutch to get us to the other side. While coffee is a pleasurable part of your lifestyle, there are other factors that make a bigger impact on your health such as eating a balanced diet, exercising and maintaining a healthy weight. But drinking coffee is certainly a delightful addition to those key health factors.

References:

1. https://www.hsph.harvard.edu/news/hsph-in-the-news/is-coffee-good-or-bad-for-your-health/
2. https://www.hopkinsmedicine.org/health/wellness-and-prevention/9-reasons-why-the-right-amount-of-coffee-is-good-for-you
3. https://www.healthline.com/nutrition/top-evidence-based-health-benefits-of-coffee#The-bottom-line
4. Carlström, M., & Larsson, S. C. (2018). Coffee consumption and reduced risk of developing type 2 diabetes: a systematic review with meta-analysis. Nutrition reviews, 76(6), 395–417. https://doi.org/10.1093/nutrit/nuy014
5. Stevens, L. M., Linstead, E., Hall, J. L., & Kao, D. P. (2021). Association Between Coffee Intake and Incident Heart Failure Risk: A Machine Learning Analysis of the FHS, the ARIC Study, and the CHS. Circulation. Heart failure, 14(2), e006799. https://doi.org/10.1161/CIRCHEARTFAILURE.119.006799
6. Wang, L., Shen, X., Wu, Y., & Zhang, D. (2016). Coffee and caffeine consumption and depression: A meta-analysis of observational studies. The Australian and New Zealand journal of psychiatry, 50(3), 228–242. https://doi.org/10.1177/0004867415603131
7. Sirotkin, A. V., & Kolesárová, A. (2021). The anti-obesity and health-promoting effects of tea and coffee. Physiological research, 70(2), 161–168. https://doi.org/10.33549/physiolres.934674
8. Hong, C. T., Chan, L., & Bai, C. H. (2020). The Effect of Caffeine on the Risk and Progression of Parkinson’s Disease: A Meta-Analysis. Nutrients, 12(6), 1860. https://doi.org/10.3390/nu12061860