What the research says — and doesn't say — about caffeine and what comes after.
Coffee drinkers have less liver disease than non-drinkers, and that finding keeps turning up across very different studies. It is one of the more consistent ...
If you’ve ever been told to go easy on coffee because of your eyes, you may have wondered whether that’s real. I read five papers on caffeine and eye pressur...
If you have gout, or a parent who does, someone has probably told you to cut back on coffee. I wanted to see whether that advice rests on anything. I read fi...
If you have ever had a kidney stone, you have probably been told to drink more water, and someone may have told you to cut back on coffee. I wanted to see wh...
Ask around about caffeine and you’ll hear that it “leaches calcium” and weakens bones. I wanted to know how much of that holds up, so I read four papers that...
When people hear that a ringing in their ears has started, one of the first pieces of advice, from friends, forums and sometimes clinicians, is to cut the co...
A reader emailed after her psychiatrist mentioned, almost as an aside, that her new prescription might make her “feel her coffee more than usual.” She asked ...
A reader wrote in last month after a genuinely unsettling appointment: her son’s psychiatrist asked, almost in passing, whether he’d had any caffeine that mo...
You felt it mid-sip: a flutter, a thud, a beat that seemed to skip and land wrong. Your hand goes to your chest. You google “does caffeine cause heart palpit...
A reader wrote in after reading our piece on why the afternoon crash hits some people harder than others, which mentions in passing that “pregnancy and certa...
Someone in a hypothyroidism forum asks a version of this question every few weeks, usually right after they’ve made a change they were proud of: I switched f...
If you’re up at 2am with the sheets kicked off and the fan going, “does my coffee habit have anything to do with this” is a reasonable question to be asking ...
A patient told me recently that she’d switched from drip coffee to a French press “because it’s healthier — less processed, less paper waste.” I understood t...
Someone told me about this years ago like it was a magic trick — drink your coffee, then go straight to sleep for twenty minutes, and you wake up hit twice a...
A reader named Marisol wrote in after our piece on coffee, tea and iron with a sentence that has been sitting with me since: her haematologist was far more e...
I want to start by narrowing this question, because it arrives as one question and it is actually three, and the three have completely different answers. Two...
Someone asks me some version of this question almost every week, and it usually arrives already half-answered: I’ve cut out coffee because of my iron — herba...
Walk down the functional-drink aisle and count how many packages say the word cortisol. Mushroom coffees, evening blends, “stress support” lattes, adaptogen ...
The most common thing I hear from people defending their afternoon coffee is some version of: “caffeine doesn’t affect my sleep — I’m out cold by eleven.”
There’s a small, common assumption tucked inside the word “decaf” — that the caffeine has been taken out, full stop, and what’s left is a coffee you can drin...
If you’ve ever tried to get a straight answer on caffeine and migraine, you’ve probably come away more confused than when you started. One source tells you c...
Most of what you’ll read on this site is a case against leaning on caffeine — the wrecked afternoons, the tolerance treadmill, the sleep you don’t realize yo...
“Coffee dehydrates you, so drink an extra glass of water for every cup.” You have almost certainly heard some version of that, probably delivered with total ...
Every few months a headline reminds you that coffee raises your blood pressure, and every few months another one tells you coffee is good for your heart. Bot...
Every few weeks someone forwards me the same claim, usually with an exclamation point: chocolate doesn’t have caffeine, it has theobromine, and theobromine i...
A reader emailed me a screenshot of a supplement label — caffeine and L-theanine, in a tidy 1:2 ratio — and asked the question I get more than almost any oth...
A patient in her second trimester asked me this one recently, and she asked it the way a lot of people do — already half-relieved, because a wellness article...
If you’ve cut back on coffee and then found yourself lying awake after an evening square of 85 percent dark, you’ve probably wondered the obvious thing: how ...
A patient brought her two-week-old to a visit recently and asked, almost apologetically, whether she had to give up her morning cup entirely now that she was...
Of all the questions readers send me, “should I switch from coffee to matcha?” is the one I most consistently answer with another question: what part of coff...
Patients ask me a version of this question every week. They are on a 16:8 or an 18:6 schedule, they have figured out that plain coffee is fine, and they want...
A friend of mine started drinking yerba mate last fall on the recommendation of a trainer who told her it had “more caffeine than coffee but cleaner.” She la...
About a third of the patients who come to me asking for “a nutrition plan” are really there because they’ve started to suspect that their coffee is hurting t...
I see the same question in clinic three or four times a month. A patient sits down, pulls out a bag of chicory coffee, and asks why something so frequently r...
The question lands in my inbox at least once a week, usually from a reader who has just been diagnosed with prediabetes or who is tracking glucose with a con...
A friend texted me last spring with a screenshot from an Instagram wellness account claiming that “decaf coffee is one of the worst things you can drink.” Sh...
People lump them together — “coffee without the caffeine” — and then get confused when they don’t taste the same, or when the decaf still gives them heartbur...
A couple of years ago, the big claim in the coffee-adjacent internet was that a morning cup could make you productive. Now the pitch has flipped. Every third...
When a pregnant client asks me whether they can drink mushroom coffee, there are really two questions tangled together: one about caffeine, and one about the...
This question comes up in my clinical practice more than almost any other coffee-alternative question. Pregnant clients have usually already cut caffeine (or...
When I was reporting on addiction medicine a decade ago, I was surprised to learn that caffeine withdrawal was a formal diagnostic entity. I had thought of c...
One of the most common questions I get from clients cutting caffeine is the most practical one: how long is this going to last?