Coffee: exactly how much is too much?

We Aussies sure love our coffee. According to global business data platform Statista, Australians will consume around two kilograms of coffee per person this year. While most of us will usually only indulge in a cup or maybe two each day, McCrindle market research has found that 28 percent of Australians drink three or more cups a day.

While moderate amounts of caffeine may offer health benefits such as a reduced risk of heart failure and lower body fat, drinking too much of the stuff can do more than just give you the jitters. New University of South Australia research has found that drinking too much coffee could increase your risk of developing serious health conditions.

Caffeine cuts close to the bone

UniSA researchers have revealed that excess caffeine may be linked to an increased risk of developing osteoporosis. They investigated the effects of coffee on how the kidneys regulate calcium levels in the body. Results showed that high doses of caffeine consumed over a six-hour period almost doubled the amount of calcium lost in urine.

“While coffee has its perks, it’s also important to acknowledge its fallbacks,” says UniSA’s Dr Hayley Schultz. “One being how our kidneys handle calcium. Our research found that people who consume 800mg caffeine over a typical working day have a 77 percent increase in calcium in their urine. This creates a potential deficiency that could impact bones.”

According to the study’s co-researcher, UniSA’s Dr Stephanie Reuter Lange, the average daily intake of caffeine is about 200mg. That’s roughly two cups of coffee. While drinking eight cups may seem like a lot, there are groups who do fall into this category.

People at risk include teenagers who binge-consume energy drinks while their bones are still developing. It also includes professional athletes who use caffeine for performance enhancement, as well as post-menopausal women. After menopause, women often have low blood calcium levels due to hormonal changes. They also often aren’t getting enough calcium-rich foods in their diet.

Too much a bitter brew for brain health

While many of us turn to a cuppa for a boost, further UniSA research has found that too much coffee could be dragging us down rather than perking us up. Especially when it comes to brain health. The researchers discovered that high caffeine consumption is associated with smaller total brain volumes and an increased risk of dementia.

The study assessed the effects of coffee on the brain among 17,702 participants of large-scale biomedical database UK Biobank. They found that those who drank more than six cups a day had a 53 percent increased risk of developing dementia.

“Accounting for all possible permutations, we consistently found that higher coffee consumption was significantly associated with reduced brain volume,” says lead researcher Kitty Pham. “Essentially, drinking more than six cups a day is putting you at risk of brain diseases like dementia and stroke.”

Professor Elina Hyppönen, senior investigator and Director of UniSA’s Australian Centre for Precision Health, says while the news may be a bitter blow for coffee lovers, it’s all about finding a balance between what you drink and what’s good for your health.

“As with many things in life, moderation is the key,” she says. “Typical daily coffee consumption is somewhere between one and two standard cups.

“Of course, while unit measures can vary, a couple of cups of coffee a day is generally fine. However, if you’re finding that your coffee consumption is heading up toward more than six cups a day, it’s about time you rethink your next drink.”