Over 180 million Americans start the day with coffee to get going. Some people enjoy their coffee and apparently have no health issues with drinking it. There are, however, some unfortunate side effects of coffee, particularly when it becomes so addictive that you find it difficult to go a day without it.
- Coffee and Hydrochloric Acid
Drinking coffee on an empty stomach, such as first thing in the morning, stimulates hydrochloric acid (HCI) production. This can be a problem because HCl should only be produced to digest meals. If your body has to make HCl more often in response to regular cups of coffee, it may have difficulty producing enough to deal with a large meal.
Protein digestion in particular is affected by a lack of hydrochloric acid in the stomach and protein based foods can pass into the small intestine before being properly broken down. Undigested protein is associated in a variety of health problems, from gas and bloating to IBS, diverticulitis and even colon cancer.
Given this, it’s important to limit anything that interferes with its proper functioning.
- Ulcers, IBS and Acidity
Many of the compounds in coffee like caffeine and the various acids found in coffee beans can irritate your stomach and the lining of your small intestine. It’s a known problem for those suffering from ulcers, gastritis, IBS and Crohn’s disease and doctors generally advise patients with these conditions to avoid coffee completely.
Ulcers are caused by the H. pylori bacteria. However, the acidic effect of coffee on the stomach may contribute to providing the weakened stomach lining necessary for H. pylori to take hold initially.
Drinking coffee can also irritate the lining of the small intestine, potentially leading to abdominal spasms, cramps and elimination problems, often alternating between constipation and diarrhea. This condition is known as irritable bowel syndrome (IBS) and more and more people are being diagnosed with it in recent years.
- Heartburn and Reflux
Coffee can lead to acid reflux and heartburn due to the way it relaxes the lower esophageal sphincter. This small muscle should remain tightly closed once you’ve eaten to prevent the contents of your stomach from coming back into the esophagus and burning its delicate lining with hydrochloric acid.
Caffeine is known to relax the esophageal sphincter, so while soda and caffeinated energy drinks can also contribute to heartburn; coffee is particularly problematic. Even decaf regularly causes heartburn for some people and researchers suspect other compounds in coffee also contribute to acid reflux.
- Coffee as a Laxative
Drinking coffee can stimulate peristalsis, the process in the digestive tract that makes us head for the bathroom. Some people use it deliberately as a laxative, but that can be problematic.
By stimulating peristalsis, coffee can promote increased gastric emptying, whereby the stomach’s contents are quickly passed into the small intestines, often before the digesting food has properly broken down.
In this partially digested state, it is much more difficult to absorb from your food. It also increases the chances of irritation and inflammation within the gastrointestinal tract.
- Mineral Absorption, Your Kidneys and Coffee
Heavy coffee drinkers may have difficulty getting enough minerals in their diet, even if they eat mineral rich foods or take supplements. This is because coffee affects iron absorption in your stomach and particularly your kidneys’ ability to retain calcium, zinc, magnesium and other important minerals.
While all of these minerals are vital for good health, from a digestive standpoint, any interference with magnesium absorption is particularly worrying as it is necessary to maintain bowel regularity and so many of us are already magnesium deficient.
6. Coffee, Stress and Tension
Drinking lots of coffee will promote the release of the stress hormones cortisol, epinephrine and norepinephrine. These chemicals increase your body’s heart rate, blood pressure and tension levels – the old ‘fight or flight’ response.
We often say we need to drink coffee to give us energy. But for many of us, it has gone further than just energy and turned into a kind of jittery tension that is always on and makes it difficult to relax. Maybe it pushes you to get through the paperwork, but longer-term the health implications of this kind of ongoing stress are significant.
Turning on the stress hormones with a cup of coffee when you’re eating also interferes with the digestive process. When you’re in ‘fight or flight’ mode, your body will divert its resources to being ready for a potential threat and digestion suffers as a result.
Finally, the caffeine in coffee is known to interfere with GABA metabolism. Gamma-aminobutyric acid is a neurotransmitter involved in regulating mood and stress levels. It should also have a calming effect on the gastrointestinal tract.
Your mood and your digestive system are surprisingly interrelated. Unfortunately, when you drink a lot of coffee the high levels of caffeine in it can negatively affect both of them.