By Dr. Colin Michie

Dr. Colin Michie has worked as a paediatrician in the United Kingdom, Africa, the Caribbean and the Middle East. He is specialised in nutrition, haematology and infectious diseases. Now the Associate Academic Dean for the American University of the Caribbean Medical School in St. Maarten, his enthusiasm is training medical students and healthcare teams to ensure they deliver better value healthcare.

Rituals often guide our choices. What do you repeat, repeat then repeat again every day?! Many of us share the vice of drinking coffee. Over 80% of American adults do this daily, each cup containing between 40 and 150 mg of caffeine. Caffeine is probably the most widely consumed psychoactive agent. And just that luscious coffee scent is sufficient to work for some on a Marigot morning! Right now, coffee is a leading indulgence and real gasoline in the lives of many St. Martiners.

Caffeine has a unique flavour profile, enhancing the hedonistic appeal of beverages. As a consequence, remarkably few sodas, for example, are now caffeine free. Caffeine is found in many over-the-counter medications from appetite suppressants to decongestants. A dose of 400 mg a day of caffeine is regarded as safe for healthy adults; a dose of approximately 10 grams is lethal.

Caffeine energises us, making us more alert, enhancing cognition. The term “nootropic”, invented in the 1970s, defines this effect. It might help your brain over the long-term too. Drinking coffee in moderation reduces degeneration of the synaptic connections between nerve cells. Coffee consumption is associated with lower rates of Alzheimer’s and Parkinson’s diseases, particularly in men. Therapeutic trials in the elderly are in progress. Caffeine enhances muscle performance, increases blood pressure and heart rate. It is a mild diuretic even when taken in moderation. In some, it can cause tremor and anxiety. Is coffee-drinking an addiction? It can certainly become a habit, and if a frequent user stops, they will notice withdrawal headaches. However, in humans generally do not become dependent on this substance as they might on alcohol or cocaine.

Caffeine is made by many different types of plants. Apart from coffee, tea and cocoa beans, there are kola nuts, yerba mate, yaupon holly, guarana, guayusa, damiana and yoco. Each of these plants has other distinctive phytochemicals with pharmacological effects too – they have their own consumer cultures. Of these botanical powerhouses, guayusa leaves achieve the highest caffeine concentration. Plants usually synthesise caffeine as an insecticide. Among the Coffea bushes, Arabica generally has less caffeine than Robusta, although levels will vary with the roasting conditions used to prepare the beans. Curiously, some citrus plants produce low levels of caffeine in their flowers: this has been found to give visiting bees an extra buzz that helps them remember to return to them!

Trade in coffee beans originated in Africa: They were exported from Ethiopia to the Yemen by Somali merchants in the late 15th century. Coffee was made by Turkish slaves in Malta in the 16th century. Coffee was served in Oxford with milk and sugar, by 1654. Women were often banned from the early English coffee houses. In 1674, women excluded in this way wrote in a paper “the Excessive Use of that New-fangled, Abominable, Heathenish Liquor called COFFEE ...has...Eunucht our Husbands, and Crippled our more kind Gallants, that they are become as Impotent”. A Swiss visitor to London in the 1720s noted social specialisation among many of London’s coffee houses. Some were for ‘learned scholars and for wits’; some were for ‘dandies’, ‘politicians’ and ‘professional newsmongers’, while ‘many others are temples of Venus.’ Today’s coffee houses might differ from this, but they market many products other than coffee – be careful of all that unnecessary sugar and calories!

Caribbean coffees

Our region is rich in distinctive coffees. Santiago Atitlan in Guatemala, Finca Santa Maria from the Honduras, Nicaraguan Ceocafen, Altura Tollan from Mexico, Medellin in Colombia, Bleu from Haiti, Blue Mountain from Jamaica, served alone or in blends, in pocillos, as cortados, cremes, tintos, breves, doppios or corettos. Delicious words that have become a lingua franca – and there are deeper aspects to the ritual – is your coffee Fair Trade? Organic? Blended? Decaffeinated? Flavoured? The Coffee Cultural Landscape of Colombia was declared a World Heritage site by UNESCO in 2011 because of international interests in preserving an agricultural structure that produces this valued commodity on traditional smallholdings.

So popular is coffee that shortages and sometimes religious recommendations have driven the manufacture of substitutes. These ersatz coffees have been made from acorns, roasted grains, okra seeds, sassafras pits, dandelion root and roasted chick peas. The “Camp” product was marketed in Glasgow, Scotland, in 1885 by Campbell Paterson, who based his recipe on roasted chicory root.

Caffeine the drug

If you survey the genes of large numbers of people, it becomes possible to find some genes that identify ardent aficionado coffee-drinkers! By contrast, genetic markers have not been found for those that are drinkers of soda, juices or tea! Further, there is a genetic link with bitter taste perceptions and caffeine use. Those that drink more coffee have a genetic predisposition to enjoy bitter flavours.

Caffeine has many actions at a cellular level. It blocks several receptors and influences an array of enzymes. This results in its multi-systemic effects. Its stimulatory effect is important for premature babies, in whom caffeine is carefully prescribed (and its levels are measured on blood tests) to ensure that they breathe regularly. A drink of coffee will contain more than just caffeine. There are those lovely oils that make the drink frothy. There are many other phenolic compounds, such as bitter trigonelline, and then there are the antioxidants! In some, dietary analyses show that over half the antioxidants in an individual’s diet are delivered by coffee, making this drink healthier than one might expect. Dietary antioxidants are most commonly found in plants and reduce the ravages of free radicals.

Caffeine is easily absorbed through the skin. This has resulted in many new cosmetic products, the precise merits of which are not always well established. Caffeine will increase local blood circulation. In some experiments, it also improves growth rates of hair. Any benefits of caffeinated creams or shampoos to those trying to thicken hair or reduce cellulite are not likely to be particularly strong, or the same for everybody!

Caffeine cautions

Caffeine-containing drinks, even in moderation, will reduce the ability to sleep in most people. Half of the caffeine you drink will be broken down in five to 10 hours, so it is wise not to indulge in the evenings. There is variation in this time – some are more sensitive! Caffeine can contribute to those midnight visits to the loo too...

Caffeine is not for everyone. For generations, Caribbean mothers have discouraged its use in pregnant and lactating mothers and children. This is wise, as caffeine persists for longer in their systems where it increases heart rates, blood pressures and alters fluid balances, causes weight gain. Caffeinated drinks upset sleep cycles crucial to children’s rest and normal development. These products will contribute to mood swings and bed-wetting in children. We need to be vigilant – it is estimated that 68% of American children under 12 years old consume 25 mg caffeine daily, mostly in the form of caffeinated drinks. Caffeinated alcohol drinks have been restricted in much of America because of their risks. Caffeine can reduce the depressant effects of alcohol so abusers are more likely to be involved in accidents. However, the traditions of “Irish coffees”, in which the caffeine dose tends to be low, show no signs of disappearing!

The final expresso

Coffee is a common pleasure. Its effects on our lives, culture and health are many, significant and potentially positive if taken in moderation. As with many items in our pantries and bathrooms, caffeine’s inclusion is not always supported by trustworthy science. However, its potential to benefit our minds is exciting – watch this space!