Do you love your coffee? And if you do, do you feel guilty about it? After all, coffee seems to be bad for you and many health experts discourage its consumption. But as with most things concerning health and nutrition: It’s not black and white. We all know people who can guzzle a “venti” (20 fl oz = 600 ml) and still have a nap afterwards, when others only so much as sniff an espresso and are wired all day long. That’s because how you respond to caffeine - coffee’s most predominant active compound - is governed by your genes, some of which affect the way your liver processes caffeine, others influence how the brain reacts.
Coffee and Blood Sugar Levels If you are stressed - and who isn’t these days - or are struggling with your weight, you should learn how to control blood sugar levels. You need to avoid sudden spikes, because high blood sugar levels stimulate the release of insulin, which in turn contributes to weight gain. Caffeine, a stimulant, does raise blood sugar levels. However, a Finnish study found that coffee increases insulin sensitivity (that’s a good thing) and lowers the risk for diabetes II. This is effect is attributed not to caffeine, but chlorogenic acid, an antioxidant in coffee. Chlorogenic acid is also responsible for many of the other beneficial properties of coffee.
So, coffee does raise blood sugar levels to some extent. We all love a biscuit or even a slice of cake alongside a cup of coffee, but combining coffee with sugar triples it's effect on blood sugar. Bad news, I know. So on to the good news …
Coffee and cardio-vascular disease Coffee is often thought to adversely affect the heart. However, according to an article published in Current Vascular Pharmacology in 2014, it is actually beneficial when consumed in moderation. Coffee lowers the risk for stroke and it does not even affect blood pressure to any great degree, but patients suffering from arrhythmia should avoid it. A word of warning though: Some people’s genetic make-up causes them to metabolise caffeine more slowly, and for them, there is indeed an increased risk of non-fatal heart attacks. (Fast caffeine metabolisers, on the other hand, actually lowered their risk of heart attack through coffee consumption.) Also, even if blood pressure is not greatly affected in healthy people, you should exercise caution and steer clear of coffee if you know that you suffer from hypertension.
But coffee does hurt the stomach. Doesn't it? It appears that even the most stubborn rumours about the ill effects of coffee are being overturned. A 2013 cross-sectional study in Japan found no correlation between coffee consumption and stomach ulcers, upper intestinal ulcers, or heartburn.
More good news Coffee has been found to protect from Alzheimer’s and Parkinson’s disease, depression, liver cirrhosis and liver cancer. Moreover, higher coffee consumption was found to significantly reduce the risk of recurrence of colon cancer, and reduces the overall risk of mortality meaning: Coffee makes you live longer - at least as long as you do not overdo it.
Who should avoid coffee? If your genes have not equipped you to tolerate coffee well, you very likely already noticed. If it makes you feel jittery, wired, causes tremors and gives you palpitations - avoid. You won’t need me to tell you that. Also, coffee is undoubtedly an addictive substance, as anyone who has ever gone through withdrawal will know, and that in itself will put a lot of people off who would rather not go there.
Pregnant and breastfeeding women and those trying for a baby should avoid coffee as it has been linked to miscarriage, stillbirth, premature delivery and lower birth weight. If you can’t live without the stuff, do not have ore than one cup a day.
If you are not sure whether or not you are a slow metaboliser - whose risk for heart disease, if you remember, is increased when they drink coffee - and would like to find out, you could do a gene test, which have recently become available at very affordable prices. (Note: The tests look at a number of health genes, not just the way you metabolise coffee.)
How to make your coffee The way you make coffee can change its properties: Boiled and unfiltered coffee may raise cholesterol and triglycerides, and paper-filtered coffee appears to contribute to inflammation. A possible reason for this is that with this method, the beneficial polyphenols in coffee are filtered out.
Consider what you’re adding Much of what gives coffee a bad reputation is not so much the coffee itself, but ingredients we like to add to it: Coffee as such has 0 calories. It may contribute to weight gain by raising blood sugar levels, but all by itself, it won’t do much damage. Consider, however, what you add to it: sugar, including syrups, lead to much greater blood sugar spikes and thus greater insulin excretion. Sugar also has powerful pro-inflammatory properties, and avoiding it is generally a good idea. Milk and cream (and sugar) all increase the calorie content of your coffee. And need I even mention marshmallows?
On the other hand, you can improve on the properties of coffee by adding either cinnamon or ginger to it. Both substances have been tested in combination with coffee - albeit only in vitro - and were found to have enhanced anti-radical and anti-inflammatory properties. Other spices that go well with coffee are cardamom, cloves, or saffron.
Is decaf a good alternative? No, is the short answer.
First of all, be aware that “decaffeinated” does not mean that the caffeine content is zero. Processing usually removes 97% of the caffeine. Most commercial brands use chemical solvents to remove caffeine from the green coffee beans, and although the industry ensures us that there will be no residues when we drink it, I personally just don’t like the thought, and it will still impact on the environment.
How much coffee is ok? It appears that coffee consumption “in moderation” is not only harmless, but even healthy for most people. But how much is “moderate”? I’ve seen recommendations that say up to 600 mg of caffeine daily is ok, but most are lower, 400 - 500 mg. Translated into cups of coffee this is approx. 4 - 5 cups. That amount of coffee is also associated with the lowest risk of death (meaning: people drinking less than that are at a higher risk of death!).
So, that’s the lowdown on coffee. If you would like to read more on coffee, click here. Or - better still - sign up to my newsletter. Tomorrow morning's edition has more on antioxidants and a recipe for cinnamon almond latte.