Coffee Caffeine - Angel or Demon?
Updated: Dec 12, 2019
Coffee is one of the most popular drinks in the world. But what is it about coffee that makes it so appealing? Some say taste, some say the caffeine, some say both. In this post I want to focus on the effects of caffeine on the body, weight management, and some dietary considerations when choosing how to drink your coffee.
The Caffeine Fix
Caffeine is a psychoactive stimulant that raises the rate at which neurons in the brain fire, stimulating the central and sympathetic nervous systems. As the brain stimulates our nervous system, our adrenal glands release the hormone cortisol. Cortisol elevates the heart rate and blood pressure, increasing our sense of alertness. Glucose releases from the liver and the pancreas releases insulin so that the glucose can make its way into our cells for fuel. It's quite a domino effect.
So now we're feeling great, pumped up, energised and ready to take on the world. The caffeine has literally put us into "fight or flight" mode. But too much caffeine can put our adrenal glands under undue stress as they are being constantly stimulated to produce hormones. This in turn can contribute to adrenal fatigue syndrome (AFS) that I recently wrote about in another blog post.
Morning coffee, habit or necessity?
Our cortisol production is naturally elevated in the morning because one of its functions is to help us wake up by countering the effect of the melatonin we produced to help us sleep. When our adrenals are fatigued, our natural cortisol production cycle can suffer. We respond by having a morning coffee that basically kick-starts the cortisol production off for us.
I often hear the phrase "I can't function without my morning coffee" - it is actually very true for some people. Likewise, in the afternoon, once the caffeine has worn off and we experience a bit of crash due to low blood sugar, we reach for another coffee, or have a sugary snack, or both. It can become a vicious cycle. Our intake of caffeine can in itself become our own worst enemy if we don't pay attention to how it affects us.
Caffeine is also known to block the neurotransmitter called adenosine. Adenosine is used in various body functions including making us feel sleepy and drowsy. Therefore in the evening when our body is releasing chemicals and hormones to ready us for sleep, caffeine's stimulatory effects and ability to interfere with adenosine may lead to poor night's sleep or even insomnia. In the morning though, a fresh cup of coffee will fix all that as we start the caffeine-cortisol cycle off again.
Some people are more sensitive to caffeine than others. We also become more tolerant to it over time; meaning we need more caffeine to get that kick we're chasing. I myself am sensitive to caffeine. I can literally feel it kick in after about 10-15 minutes. If I were to have two cups back to back, I will get heart palpitations and start to sweat. I stopped drinking coffee for several years and have only just this year reintroduced it to my diet. I limit my caffeine intake to just a couple of times a week and only when I want to use the caffeine's effects to my advantage.
Caffeine and Weight Loss
There is inconclusive evidence if caffeine aids weight loss. As a stimulant however it provides us more energy that can be used to burn more calories via physical activity. Caffeine also stimulates thermogenesis (thermogenics) in the body. Thermogenics burns calories to produce heat but it is unlikely sufficient to cause significant weight loss.
I have heard people say they only have a coffee for breakfast. I see coffee for breakfast as skipping one of the day's most important meals, unless you are fasting. It also might result in a lower calorie intake for the day which is helpful in managing weight; but is not an ideal approach and one I would not like to see a client practice.
I have also heard people say they gain weight when not drinking coffee. The gain is unlikely due to the caffeine helping to keep weight off. It is more in my experience that the coffee is replaced with something else that gives the desired boost; typically a carbohydrate heavy, sugary snack which only serves as a short-term energy boost. Once the sugar crash hits, another snack is needed to give that boost again. This is most likely where the weight gain is coming from.
A good food swap out for a sugary snack when you need some energy is a piece of fruit (not fruit juice) - eat the fruit.
Dietary & Weight Management Considerations
How we drink coffee is mostly personal taste; but it can be impacted by dietary intolerances (e.g. lactose intolerant) or choices. I drink black coffee for example because I choose not to drink milk.
We also need to consider our weight management goals. For example, if you have a few milky coffees (e.g. cappuccino, latte, iced coffee etc.) a day, this could add up to a few hundred calories. Whilst I don't like to count calories, we still need to be aware of what we are consuming and its impact. Some people might counter that argument by choosing low fat or skim milk as they may contain less than half the calories of full fat milk. This is a logical swap out and totally fine, just keep the number of cups per day in perspective; if not for calories, for the caffeine and your overall well being.
Swapping out milk with milk alternatives (e.g. soy milk) may have little effect on weight management so do your research and plan ahead. Here is a blog I did comparing milk alternatives to get you started.
Avoid adding sugar (or flavoured syrups) to coffee is something I recommend. The caffeine is already going to release energy into our system and adding sugar will cause more insulin to be released and potentially contribute to our sugar crash later on. Our taste buds will get used to the reduced sweetness over time so if you habitually add a sugar to your coffee, try weening yourself off it over a few weeks. I used to add one sugar to my black coffee, now most of the time I don't add any.
Until Your Next Coffee Break...
Having a coffee a day is not a bad thing. It's a delicious drink that has spawned a new era of cafe society and it's an incredibly social way to catch up with friends and work colleagues; so why not enjoy it.
Too much though is rarely a good thing so be aware of how caffeine affects you and keep your caffeine intake in check.
If you can't go a day or two without a coffee caffeine fix, then it likely has a stronger hold on you than you do on it.