Traditionally a nation of tea lovers, and now just as fond of our coffee, most of us kick-start our mornings with a hot brew. In fact, in the UK we drink 165 million cups of tea per day and 70 million cups of coffee! But how much (if any) caffeine is too much? And are tea and coffee are good or bad for you? This week I’m going to answer these questions and give you the facts on caffeine and your favourite drinks.
Caffeine – The Facts
Caffeine is a drug, its effects include boosting alertness, mental clarity and focus and improving our mood, helping us feel like we can take on the day. It does this by stimulating the central nervous system, blocking the action of adenosine, a chemical that makes us feel drowsy and sleepy. When it wears off however, the opposite effects can be experienced – lack of energy, difficulty concentrating and feeling low. This often prompts us to reach for a second cup, and then a third, a fourth and so on… Like any drug, caffeine has the capacity to be addictive and tolerance will build up over time meaning that you have to drink more to get the same ‘buzz’.
The effects of too much caffeine can be unpleasant including sleep problems, anxiety, nervousness, shaking, headaches, nausea, appetite changes and heart rhythm disturbances. In the long run, relying on caffeine to fuel you through the day tends to drain your body’s natural energy. Another affect of caffeine is that it is a diuretic, meaning that it makes us go to the loo and lose water from the body, which can lead to dehydration.
Tea
Black, green and white teas may taste different but they actually come from the same plant, camellia sinensis. The difference is due to the way the leaves are harvested and processed. Black tea is allowed to oxidise slightly, which increases the caffeine content as well as bringing out the richer flavour. Black tea is a good source of antioxidants along with folate, magnesium, fluoride and phosphorous. It also contains theaflavin, an antioxidant that lowers cholesterol levels (1) and encourages alpha (relaxing) brain waves – the reason that a ‘nice cup of tea’ has soothing effects, while at the same time the caffeine provides a ‘pick-me-up’.
Both green and white teas contain the powerful antioxidant EGCG (epigallocatechin-3-gallate), which has been shown to have many health benefits. Green tea is one of the healthiest foods you can add to your diet, being one of the richest dietary sources of antioxidants. Its well-studied health benefits include lowering cholesterol, helping weight loss by increasing energy burning and reducing fat digestion (2), protecting the heart, lowering the risk of several diseases, protection against the flu and even against sun damage to the skin. Green and white teas are less processed, higher in antioxidants and generally lower in caffeine than black teas, making them the healthier choice.
Coffee
Coffee contains the antioxidants chlorogenic acid and caffeic acid, which have several beneficial and protective effects in the body. Coffee also contains folate, magnesium, calcium and phosphorous.
Moderate consumption of 2-4 cups has been shown in various studies to help keep the heart healthy, reducing the risk of heart disease and possibly type 2 diabetes (3). A protective effect against diseases involving cognitive decline in the elderly has also been found. Coffee may also help keep the digestive system healthy as the different antioxidants it contains help protect the digestive system against disease (4). Compounds called melanoidins are believed to encourage colon motility and anything that helps things ‘move more quickly’ is health enhancing. These health benefits are seen even with decaffeinated coffee, so it is not the caffeine causing them.
Green Coffee is ‘raw’ coffee that hasn’t been roasted, the roasting process turns coffee beans brown and gives its characteristic flavour. Green coffee contains the beneficial compounds such as chlorogenic acid, but without the caffeine. It has been shown to help lower blood pressure, balance blood sugar levels and may even help people lose weight when on a diet (5-9).
A typical coffee shop coffee can be high in calories, caffeine, fat and sugar due to what comes with it – lots of full-fat milk, extra shots and sugar-laden syrups for example. The best options are therefore either black coffee or a small cappuccino with skimmed, almond or soya milk and no sugar, syrup, cream, flavourings or other add-ins. If you simply love the taste of coffee decaf is a good option, just check with your barista that the decaf they use has been processed by the natural water-extraction process as opposed to using chemicals.
Average Caffeine Content
Espresso Shot 80mg
Cup Instant Coffee 100mg
Cup Black tea 50-80mg
Can of Red Bull 80mg
Can of Coke 30mg
Cup Green Tea 20-60mg
Cup Filter Coffee 120mg
These figures are averages but can vary quite a bit depending on variety, brewing methods etc.
My Advice
Like most things in life, balance is key where caffeine is concerned. In small amounts caffeine is fine for some people, but certainly too much will cause problems.
One of the issues is that caffeine affects everyone differently. Body size, physiology, metabolism, stress levels and how much you have eaten can all affect your reaction. This makes it hard to set safe or recommended guidelines. The Department of Health advises people not to drink more than five single espressos a day. For optimum health and energy however, I would recommend no more than 1 to 2 coffees or black teas per day. With green tea you can have more, up to about 4 or 5.
If you love your coffee, have the best quality you can, avoid instant coffee and stick to freshly ground. Decaffeinated coffee will give you the same taste and social ritual without the other effects.
Drinking an extra glass of water for every tea or coffee drunk is advisable to counteract the dehydrating effects. It is best not to drink caffeine first thing on an empty stomach and to avoid it after about 3pm to prevent sleep disturbances.
Stay away from sugar-laden energy drinks and colas and supplements containing caffeine, which can contain very high amounts. People who should avoid caffeine completely are pregnant women, anyone suffering from sleep problems or chronic fatigue and anyone with anxiety problems, as caffeine has been shown to make anxiety worse.
Cutting out caffeine suddenly can lead to ‘withdrawal’ symptoms such as extreme fatigue and drowsiness, headaches, irritability and low mood, so is not advisable. Luckily the symptoms are usually short-lived, usually lasting only a few days. If you want to reduce or cut out caffeine, do it gradually to avoid symptoms. I recommend reducing by one drink per week and if you do experience problems you can have a green tea or Beauty & Go Vitality to help you through any difficult moments. Beauty & Go Vitality contains green tea for a natural energy boost, along with other energising ingredients guarana, Ginkgo biloba, coenzyme Q10 and B vitamins to support natural energy production in the body.
References:
1. Stensvold I, Tverdal A, Solvoll K, et al. Tea consumption. Relationship to cholesterol, blood pressure, and coronary and total mortality. Prev Med 1992;21:546-53.
2. Nagao T, Hase T, Tokimitsu I. A green tea extract high in catechins reduces body fat and cardiovascular risks in humans. Obesity 2007;15:1473-83.
3. Huxley R, Lee CM, Barzi F, et al. Coffee, decaffeinated coffee, and tea consumption in relation to incident type 2 diabetes mellitus: a systematic review with meta-analysis. Arch Intern Med 2009;169:2053-63 [review].
4. Schmit, SL, Rennert HS, Rennert G, and Gruber SB. Coffee Consumption and the Risk of Colorectal Cancer. Cancer Epidemiol Biomarkers Prev April 2016 25; 634
5. Kozuma K, Tsuchiya S, Kohori J, et al. Antihypertensive effect of green coffee bean extract on mildly hypertensive subjects. Hypertens Res 2005;28:711-8.
6. Watanabe T, Arai Y, Mitsui Y, et al. The blood pressure-lowering effect and safety of chlorogenic acid from green coffee bean extract in essential hypertension. Clin Exp Hypertens 2006;28:439-49.
7. Thom E. The effect of chlorogenic acid enriched coffee on glucose absorption in healthy volunteers and its effect on body mass when used long-term in overweight and obese people J Int Med Res 2007;35:900-8.
8. Dellalibera O. Lemaire B, Lafay S. Svetol, green coffee extract, induces weight loss and increases the lean to fat mass ratio in volunteers with overweight problem. Phytotherapie 2006;4:194-7.
9. Vinson JA, Burnham BR, Nagendran MV. Randomized, double-blind, placebo-controlled, linear dose, crossover study to evaluate the efficacy and safety of a green coffee bean extract in overweight subjects. Diabetes Metab Syndr Obes 2012;5:21-7.
