Busting the caffeine myth: Yes, you can drink your morning coffee on an empty stomach
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If, like me, you find yourself reaching for a cup of coffee as soon as you wake up, you may have been prompted recently to rethink your morning ritual.
Social media has been abuzz recently with warnings about a supposed link between drinking coffee on an empty stomach and a rise in cortisol levels, which in turn has been linked to everything from feeling stressed to gaining weight.
Don’t believe what you’ve heard about coffee and cortisol. iStock
But experts say there is not enough evidence to support the claim your early-morning coffee might be bad for your health.
Cortisol and coffee
According to the Australian Government’s Heathdirect website, cortisol is a naturally occurring steroid hormone made by the adrenal glands located on top of each of your kidneys.
When you feel stressed, your body releases more cortisol into your bloodstream.
It is also responsible for that ‘fight or flight’ feeling we get, which is why it has received the rather unfortunate moniker of the ‘stress hormone’.
Recently, social media posts warned that drinking coffee on an empty stomach caused a ‘spike’ in your cortisol level.
Among those to debunk the theory was Sydney-based endocrinologist and Conjoint Associate Professor in Endocrinology at UNSW Sydney Ann McCormack, who recently wrote a piece for The Conversation.
“Cortisol levels are affected by many factors including gender, age and genetics, as well as food, exercise, stress, light and illness,” she said in her piece.
“Understanding the effect of a simple cup of coffee in the morning depends on the intricate and complex nature of these dynamics. Importantly, there have been no randomised controlled studies comparing coffee consumption on an empty stomach to having it after food.”
Coffee can increase cortisol whether you have eaten or not. Getty Images/iStockphoto
While she said coffee had been linked to a rise in cortisol levels of up to 30 per cent according to one study, it did not prove a link between increased cortisol levels and drinking coffee on an empty stomach.
Canberra-based accredited practising dietitian and nutritionist Danielle Shine is completing her PhD research on social media nutrition misinformation, so is well-placed to comment on the latest health conspiracy theory doing the rounds on sites such as TikTok and Instagram.
“The idea that drinking coffee on an empty stomach is harmful because it causes a problematic spike in cortisol is a popular claim on social media, but current evidence doesn’t support it,” Shine said.
“Cortisol naturally peaks after waking, and while caffeine can cause a small, temporary increase in cortisol − particularly in people who don’t regularly consume caffeine − there’s no good evidence that having coffee before breakfast is inherently harmful for most healthy adults because of this.”
Not that it means it is necessarily a good habit to reach for a coffee as soon as you get up.
Shine said some people who were more sensitive to caffeine might experience symptoms such as reflux, stomach discomfort, increased anxiety or jitteriness when drinking coffee on an empty stomach.
She said this “caffeine sensitivity” varied from person to person, with some people noticing effects after small amounts of caffeine while others tolerated much higher intakes.
“While some people tolerate caffeine well, others suffer caffeine sensitivity,” Shine said.
So should I refrain from drinking caffeine on an empty stomach?
Not necessarily, according to Shine, who said there was “no blanket evidence-based recommendation” to support this, and it was really up to the individual.
The hit TV show Friends revolved around the Central Perk coffee house. Warner Bros/Stan
“Ultimately, there’s no ‘one-size-fits-all’ recommendation. If consuming caffeine on an empty stomach doesn’t cause you any discomfort, there’s no evidence-based reason to avoid it,” she said.
“If coffee first thing in the morning tends to upset your stomach or makes you feel jittery, having something to eat beforehand may help.
“There’s no specific food or drink you need to consume with coffee − a simple, well-balanced breakfast is perfectly fine.
“It’s also worth considering that caffeine may not always be the cause.
“Depending on the beverage, other ingredients, like added sweeteners or dairy or plant-based milks, may contribute to gastrointestinal symptoms or discomfort in some people. It’s important to consider the entire beverage rather than assuming caffeine is to blame.”
Busting the myths
“Unfortunately, there’s a significant amount of false and misleading information about nutrition and health online,” Shine said.
“It’s important not to make major dietary decisions based on a single social media post, especially when the advice involves fear, extreme restrictions, expensive supplements, or promises of quick fixes.
“This type of content often spreads widely and is very popular because it’s engaging, emotionally appealing, and rewarded by algorithms that prioritise content likely to generate attention and interaction.”
People are being urged not to get their health and nutrition advice from social media. iStock
Shine said instead of “chasing health trends that are often based on hype rather than strong evidence” she encouraged people to focus on the “foundational habits that have consistently been shown to support good health”.
This includes eating a well-balanced diet, staying hydrated, being physically active (including regular resistance training), getting adequate sleep, limiting alcohol, not smoking, and finding healthy ways to manage stress.
“If you’re unsure whether a nutrition claim is accurate, or need support navigating your own nutrition needs or goals, seeking advice from a qualified health professional, such as an Accredited Practising Dietitian, is a good place to start.”
Please note the information in this story is general in nature. Please always consult your GP or health professional for advice that is tailored to your specific health concerns.
