Here’s how a typical morning for me used to go: Wake up, hit snooze several times, drag myself to the kitchen to make coffee, then wait for the sweet, sweet caffeine to hit my veins. I’m basically a walking but first, coffee cliché. But I mean, that phrase is all over T-shirts/mugs/café letter boards for a reason, right? So when I described my daily routine during a recent nutrition consult with Carlyn Rosenblum, MS, RD, I wasn’t expecting her first criticism to be about that particular habit. Here’s what she had to say about drinking coffee on an empty stomach before breakfast.
“There are a few reasons why coffee isn’t great first thing in the morning, especially for women,” says Rosenblum. “First, it increases cortisol, which can negatively impact ovulation, weight and hormonal balance.” The so-called stress hormone—which, among other things, helps regulate energy and makes you feel alert—fluctuates throughout the day, but is generally high in the morning and low in the evening. “Drinking caffeine first thing in the morning, when cortisol is high, blunts the hormone’s production and shifts the timing of the cycle,” Rosenblum explains. This can cause you to produce cortisol at times when it would normally drop (like at night). “Studies also show that consuming caffeine when cortisol is high can actually cause you to produce more cortisol,” she says. “While the reasoning behind this is not entirely understood, part of the reason could be related to coffee’s impact on certain vitamins and minerals.
“Cortisol is necessary for our health; however, the problem is when we are constantly stressed out, our body is continuously producing cortisol,” Rosenblum explains. “This can lead to increased blood sugar, which then leads to increased insulin hormone producing, leading to insulin resistance.” Excess cortisol can lead to effects like weight gain, sleep problems and compromised immune response.