Coffee, tea, and energy drinks fuel our mornings, our focus, and sometimes our entire lives.
But beneath the daily ritual lies a question few ever ask: is caffeine truly helping us… or just keeping us hooked?
In this episode of The Dr. Kumar Discovery Podcast, Dr. Ravi Kumar takes you deep into the biology, history, and modern science of caffeine, the most widely used psychoactive drug on Earth. You’ll learn how it sharpens the brain, enhances performance, and even supports long-term health, but also where it can quietly undermine sleep, anxiety, and blood pressure.
Episode Highlights
- The Origins — how plants evolved caffeine as both a defense and a memory enhancer
- From Kaldi to Coffeehouses — how caffeine shaped culture, creativity, and revolutions
- The Brain Effect — how caffeine blocks adenosine and amplifies dopamine and focus
- Performance Boosts — how caffeine improves endurance and reduces perceived exertion
- Memory & Motivation — the neuroscience of caffeine’s impact on learning and drive
- Long-Term Health — what studies reveal about caffeine and heart, liver, and brain outcomes
- The Polyphenol Advantage — why coffee, tea, and cocoa beat energy drinks
- The Downsides — anxiety, hypertension, reflux, and pregnancy considerations
- Caffeine Myths — the truth about “waiting 90 minutes” and afternoon crashes
- Practical Takeaways — how to find your personal caffeine “sweet spot”
Show Notes
The Science of Stimulation
Caffeine works by blocking adenosine receptors, lifting the “sleep pressure” that builds during wakefulness. This not only enhances alertness and concentration but also potentiates natural dopamine signaling—making motivation and focus feel effortless.
Beyond the brain, caffeine improves athletic performance, decreases perceived exertion, and even enhances the pain-relieving effects of common medications like acetaminophen and ibuprofen.
Long-Term Effects
Decades of epidemiologic research show that moderate coffee intake—two to four cups per day—is associated with lower all-cause and cardiovascular mortality, reduced risk of type 2 diabetes, and improved liver outcomes. These benefits may stem not just from caffeine, but from the polyphenols it comes packaged with, like chlorogenic acid and catechins.
When to Be Cautious
Caffeine can worsen anxiety, raise blood pressure in those with severe hypertension, and disrupt sleep if consumed too late in the day. In pregnancy, excess caffeine is linked with low birth weight and fetal growth restriction, so moderation is key.
And while caffeine withdrawal is real, tapering intake slowly can ease symptoms. Understanding your metabolism, and timing your last cup—is the key to using caffeine wisely.
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Cheers!
Transcript
[00:00 –> 00:29] On this episode of the Doctor. Kumar discovery, the central question is this, do the benefits of caffeine use outweigh the risks? In the right amounts, caffeine acts as a neurostimulant across the animal kingdom, including us humans. It enhances attention, sharpens recall, and tunes our neurobiology in ways that have made it the most popular psychoactive compound on earth. Social gatherings were mostly in pubs where alcohol often dulled conversation and led to chaos.
[00:30 –> 00:56] Coffee houses flipped that script. For the price of 1p, you could have a cup of coffee and join stimulating conversation. But here’s a big difference. You don’t get a big dopamine surge from caffeine like you would from nicotine or cocaine or some other addictive medication. Instead, the system becomes more responsive to the dopamine you naturally release, which makes work feel more doable and goals feel more attainable.
[00:56 –> 00:59] With the right amount of caffeine, you feel like a champion.
[00:59 –> 01:24] My name is Doctor. Ravi Kumar. I’m a neurosurgeon in search of the causes of human illness and the solutions that help us heal and thrive. I want you to join me on a journey of discovery as I turn over every stone in search of the roots of disease and the mysteries of our resilience. The human body is a mysterious and miraculous machine with an amazing ability to self heal.
[01:24 –> 01:32] Let us question everything and discover our true potentials. Welcome to the Doctor. Kumar discovery.
[01:33 –> 01:48] My name is Doctor. Ravi Kumar, and welcome to the Doctor. Kumar discovery podcast. In this episode, we’re gonna take a deep dive into the most widely consumed drug in the world, caffeine. The central question is this.
[01:48 –> 02:04] Do the benefits of caffeine use outweigh the risks? And I wanna be upfront. I’m a big coffee drinker. I love coffee, and I have come into this investigation with a bias. My bias is that I want coffee and caffeine consumption to be a net benefit.
[02:04 –> 02:18] But I’m also open, open to the possibility that caffeine may not be worth the risk it carries. I’ve done the research. I know the data, and I know the conclusion I’ve come to. So here’s the spoiler. I’m gonna keep drinking coffee.
[02:18 –> 02:41] I didn’t find enough evidence to convince me that it’s not worth it. And honestly, the benefits seem to vastly outweigh the risks, but that’s my decision. The goal of this episode is to give you the same information laid out clearly so you can come to your own conclusions. By the end of this episode, you’ll have the following. You’ll know whether the benefits of caffeine outweigh the risks for you personally.
[02:42 –> 03:07] You’ll know which forms of caffeine and what amounts are best for reaching your goals, and you’ll be able to decide based on hard data whether caffeine deserves a place in your life. So before we dive into that, let me give you a quick disclaimer. I’m a doctor, but I’m not your doctor. This podcast is for informational purposes only. It’s not intended to diagnose or treat any medical condition.
[03:07 –> 03:29] The goal here is to give you knowledge that helps you make clear, rational, and unbiased decisions about your own health. Knowledge is power. And if I can give you that knowledge, you’ll be more empowered to make your own choices. That said, it’s always wise to work with a health care practitioner. Even if you’re a doctor like I am, you should still have a doctor to help guide you through many of these complex decisions.
[03:29 –> 03:39] And finally, one more note. This podcast is separate from my role as assistant professor at UNC. So let’s get into it. What is caffeine actually? We should know that before we start talking about it.
[03:39 –> 04:03] Caffeine is a compound called a methylxanthine. It has a couple cousins you might recognize, theophylline, which was once used as an asthma treatment, and theobromine, which is found in cocoa. Methylxanthines are made by plants, and here’s the key. They’re built to fit directly into adenosine receptors in animals. Think of it like a blank key that slides perfectly into the lock, but doesn’t open it.
[04:03 –> 04:20] That’s how caffeine works. It fits the receptor, but doesn’t activate it. We’ll come back to why that matters later. But here’s something that’s super fascinating. Around a 100 different plant species produce caffeine, and many of these plants are not even related in evolutionary terms.
[04:20 –> 04:48] Tea plants, cacao, coffee, they each evolve the ability to make caffeine independently. In fact, the genes that produce caffeine in tea are completely different from the genes in cacao. They built different enzymes through different genetic pathways, yet they ended up making the same chemical. That’s called convergent evolution, And it usually means the trait or chemical end product, in this case caffeine, is extremely useful. So why do plants keep reinventing caffeine?
[04:48 –> 05:12] Because it works. Caffeine fits directly into animal adenosine receptors, and that gives the plant a tool with multiple uses. One purpose is defense. If a plant packs enough caffeine into its leaves or seeds, herbivores that try to eat it can become overstimulated, even intoxicated. At high doses, caffeine is effectively a pesticide, but caffeine also has a more subtle role.
[05:12 –> 05:43] Some plants put just the right amount of it into their nectar, and at that level, caffeine doesn’t poison insects, it sharpens them. It improves a pollinator’s memory of the flower scent, which makes the insect more likely to come back again and again. In other words, the plant gives a little dose of a smart drug to recruit pollinators for its own survival. And this property doesn’t just stop with insects. In the right amounts, caffeine acts as a neurostimulant across the animal kingdom, including us humans.
[05:43 –> 06:26] It enhances attention, sharpens recall, and tunes our neurobiology in ways that have made it the most popular psychoactive compound on earth. This story of caffeine’s rise to ubiquity begins, at least in legend, in the Ethiopian Highlands in the fourteen hundreds. A goat herder named Kaldi noticed that his goats, after chewing the red berries of an evergreen bush, became lively, prancing, and full of energy. Curious, Caldy tried the berries himself and felt a sharpening of his senses, a mild but noticeable stimulant effect. He shared them with his community, and before long, people discovered that when the beans were roasted and infused in hot water, the drink produced a wakefulness that was unlike anything else.
[06:26 –> 06:52] From Ethiopia, coffee traveled into the Sufi communities of Yemen. The Sufis practiced all night prayer sessions called dikirs, which were grueling without stimulation. Coffee became the perfect companion, allowing them to stay awake, focused, and devoted throughout the night. By the fifteen hundreds, coffee had migrated to Istanbul, where coffee houses spread rapidly. These weren’t just places to drink coffee, they became social hubs.
[06:52 –> 07:21] Inside, people exchanged poetry, debated the news, played chess, and even discussed political dissent. In many ways, these coffee houses acted like the social media of their day, energizing conversations and spreading new ideas. Because of that power, rulers alternated between tolerating coffee and banning it. From the Ottoman Empire, coffee moved along the Levantine trade routes through Venice and into Europe. In London, the first coffee house opened in 1652.
[07:21 –> 07:46] Until then, social gatherings were mostly in pubs where alcohol often dulled conversation and led to chaos. Coffee houses flipped that script. For the price of 1p, you could have a cup of coffee and join stimulating conversation. They were soon nicknamed penny universities because for that small fee, you could walk in and leave more enlightened. Coffee changed the tempo of public life in England.
[07:46 –> 08:17] At the same time, tea was shaping culture in Asia. From the Camellia sinensis plant, tea also contained caffeine, balanced by another compound called L Theanine, which smoothed out caffeine stimulation and brought focus. Tea entered Europe in the mid sixteen hundreds. In 1658, Londoners saw the first newspaper advertisement for tea, sparking a national obsession. The British quickly moved to establish their own supply, breaking dependence on Chinese tea by developing plantations in the Assam region of India.
[08:17 –> 08:57] They marketed tea as a sober, healthful drink, which again was the opposite of ale. Meanwhile, on the other side of the world, yerba mate had been a cornerstone of South American culture for centuries. Indigenous communities of Argentina, Uruguay, Paraguay, and Brazil brewed the leaves of the Ilex perguensias plant into a communal drink. Colonists and Jesuit missionaries adopted the practice in the sixteenth century, and to this day, mate is consumed from a shared gourd rich in caffeine, theobromine, and other polyphenols. So before we can understand how these drinks fit into our life and affect us, we need to understand how much caffeine they actually have in them.
[08:57 –> 09:22] The most common source is brewed coffee. One cup usually has somewhere between 70 and a 170 milligrams, depending on how strong the brew is. If you’re making drip coffee at home, a safe rule of thumb is to assume that there’s a little over a 100 milligrams in an eight ounce cup. Espresso has less caffeine per serving than drip coffee, around 60 to a 100 milligrams per shot. So a cappuccino with a single shot is usually around 80.
[09:22 –> 09:46] French pressed coffee lands in the same range as drip coffee. Tea comes in lower, usually around fifteen to sixty milligrams per cup, with most brewed green or black teas falling in the forty to fifty milligram range. Energy drinks often print their caffeine content on the can, but it can be tricky. Most are north of a hundred milligrams, and some have two servings in one can, so it’s important to read those labels carefully. Caffeinated sodas are lower.
[09:46 –> 10:10] A can of Coke has around thirty four milligrams of caffeine. Diet Coke has forty six milligrams, and Mountain Dew comes in around fifty five milligrams. Yerba mate sits closer to coffee, typically in the sixty five to a hundred and thirty milligram per cup if brewed traditionally. If you’re using tea bags instead of the gourd in infusion style, the caffeine is usually much lower. So those are the typical numbers, but the more important question is this, how much is safe?
[10:10 –> 10:36] Well, the answer isn’t the same for everyone. Each of us metabolizes caffeine differently. Variations in our adenosine receptors and liver enzymes mean that the same amount of caffeine can feel very different from one person to the other. Still, health authorities generally agree that up to four hundred milligrams per day appear safe for most nonpregnant adults. For pregnancy, the recommendation is to stay below two hundred milligrams of caffeine per day.
[10:36 –> 11:02] So to put that in perspective, four cups of coffee a day or many more cups of tea is within that limit. But if you’re someone who drinks five or six cups of coffee and barely feels it, well, that’s just your biology, and it’s a perfect example of how there isn’t a blanket rule that fits everyone. So now we come to the good stuff. We get to ask, what does caffeine actually do in the body? Remember, caffeine is a methylxanthine that fits into adenosine receptors without turning them on.
[11:02 –> 11:27] Adenosine itself builds up in the brain as we burn ATP. And remember, ATP is the main form of usable energy in your cells. When ATP gets spent, it breaks down into AMP and then into adenosine. Rising adenosine binds to the adenosine receptors in the brain, telling the brain that most of your energy has been spent and you need some rest to create more energy. This essentially creates sleep pressure.
[11:27 –> 11:57] More adenosine means more adenosine receptor activation and more sleepiness and a overall stronger push towards rest. Adenosine hits two key receptor families in the brain called a one and a two a. When they are active, they dampen alertness. They also churn down other systems that keep us on task. In several circuits, adenosine reduces the release of acetylcholine, which supports attention and wakefulness, and it restrains dopamine signaling, which supports motivation and goal directed behavior.
[11:57 –> 12:18] Adenosine receptors, when activated, are essentially off switches. So here’s where caffeine comes in. Caffeine is a competitive antagonist of those adenosine receptors. Think of the blank key in the lock analogy that I gave you earlier. It fits into the adenosine receptor without activating it and blocks adenosine from creating sleep pressure.
[12:18 –> 12:46] With that break removed, acetylcholine release is less suppressed, and dopamine signaling works more efficiently. But here’s a big difference. You don’t get a big dopamine surge from caffeine like you would from nicotine or cocaine or some other addictive medication. Instead, the system becomes more responsive to the dopamine you naturally release, which makes work feel more doable, and goals feel more attainable. With the right amount of caffeine, you feel like a champion.
[12:46 –> 13:04] There’s nothing you can’t do. This shows up in movement systems too. In the basal ganglia, there are two main pathways. The direct pathway, which helps you initiate movement, and the indirect pathway, which acts like a brake on movement. Blocking adenosine receptors with caffeine here churns that brake down.
[13:04 –> 13:27] The dopamine receptors become more active. They, in turn, don’t inhibit the thalamus, which coordinates movement. And when the thalamus is less inhibited, movement initiation feels easier, and both mental and physical activation improve. Adenosine also sits on cortical terminals that release glutamate, which is an excitatory neurotransmitter. When adenosine is high, glutamate release falls.
[13:27 –> 13:57] Block the adenosine receptors with caffeine, and glutamate release rises, which further supports motor drive and attention. Subjectively, this often feels like a lower rating of perceived exertion. The same workout feels a little less hard, so you can push a little further. These effects come in very useful in sports and physical activity. Caffeine is an ergogenic aid, which simply means performance enhancing drug, and its use is ubiquitous throughout the world of sports and physical performance.
[13:57 –> 14:26] The most supported way to use it is a dose of about three to six milligrams per kilogram of body weight taken roughly sixty minutes before training or competition. That dose consistently lowers perceived exertion and improves time to exhaustion. Caffeine also touches memory systems. In the hippocampus, adenosine tone normally pulls down acetylcholine release. When you block adenosine receptors, acetylcholine signaling rises and memory circuits work more efficiently.
[14:27 –> 14:49] In one study, a single two hundred milligram dose given right after a learning session improved memory discrimination when tested twenty four hours later. In plain terms, memory storage got a boost. Another common reason people reach for caffeine is for headaches. There’s a reason for that. Adenosine signaling in the brain promotes vessel dilation and can contribute to headache pain.
[14:49 –> 15:29] If you block adenosine receptors with caffeine, you shift tone towards vasoconstriction, which can reduce headache symptoms for some people. A single two hundred to two hundred and fifty milligram dose of caffeine can lower cerebral blood flow by about 20 to 30%, which lines up with the relief that many people feel. Because of this vasoconstrictive quality, you may also see small transient bumps in systolic and diastolic blood pressure, especially if you’re not a regular caffeine user. Caffeine’s vascular effects also vary across the body. It tends to constrict cerebral vessels at rest, but during exercise, local metabolic signals in working muscle dominate and drive vasodilation.
[15:29 –> 16:00] So muscle perfusion is maintained or improved by higher cardiac outputs when caffeine is used with exercise. Another effect of caffeine on the body is that if you’re new to caffeine, you might notice that you need to urinate soon after drinking it. Caffeine reduces sodium and water reabsorption in the proximal tubule of the kidney, which increases urine output. With regular use, the kidneys adapt and the diuretic effect fades. For habitual users, coffee and tea contribute meaningfully to daily hydration just as much as water.
[16:00 –> 16:23] So if you drink coffee or tea every day, they are the equivalent to water in their ability to hydrate your body. Caffeine also enhances pain relief. Adding about one hundred to two hundred milligrams of caffeine to an analgesic like acetaminophen, ibuprofen, or aspirin increases the effectiveness of these drugs. That’s why products like a sedger migraine include caffeine. So those are the short term effects of caffeine.
[16:23 –> 16:54] But what are the long term effects of drinking coffee and tea habitually? Every day for years. Observational research links coffee intake of roughly two to four cups per day with lower all cause mortality and lower cardiovascular mortality. Large US cohorts found similar patterns, including the NIH AARP study of about 400,000 adults, where higher coffee intake was associated with lower total and cause specific mortality. Tea shows more modest associations at around one and a half to two cups per day.
[16:54 –> 17:29] Coffee intake is also associated with a lower risk of type two diabetes on the order of six to eight percent per additional daily cup. Decaf trends in the same direction, which suggests that non caffeine compounds in coffee, such as chlorogenic acids, may contribute to this effect. Liver outcomes are another consistent signal. Higher coffee intake has been linked with lower risk of hepatocellular carcinoma, chronic liver disease progression, and nonalcoholic fatty liver disease. Finally, there is a robust association between caffeine or coffee intake and lower Parkinson’s disease risk.
[17:29 –> 18:06] Mechanistically, this fits with what we discussed. By blocking adenosine receptors that sit alongside dopamine receptors in the indirect pathway, caffeine makes dopamine signaling more effective. Even with lower dopamine output, those circuits can function a bit better, which may explain the epidemiology and some of the symptom benefits seen in these studies. Another thing to consider is that many of the long term benefits we see with coffee, tea, cocoa, and yerba mate are not just from caffeine itself, but from polyphenols that come packaged with it. In the American diet, coffee is the single largest source of polyphenols.
[18:06 –> 18:37] Analyses from the NHANES surveys suggest that coffee accounts for nearly 40% of all dietary polyphenol consumption in The US. The main one in coffee is chlorogenic acid, the most abundant molecule in brewed coffee. Chlorogenic acids have been linked to lower blood pressure, better endothelial function, and improved handling of blood sugar after meals. Tea is another major polyphenol source. Its key compounds are catechins, especially EGCG, the most abundant and best studied catechin in green tea.
[18:37 –> 19:11] Catechins have been shown to lower LDL cholesterol, improve blood pressure, enhance glycemic control, support endothelial function, reduce inflammation, and even improve certain aspects of working memory. Cocoa has its own set of compounds called flavonols. Cocoa flavonols improve endothelial function and are associated with reduced cardiovascular events. Yerba mate also carries caffeine with a mix of polyphenols and theobromine. The traditional infusion methods deliver a strong antioxidant and anti inflammatory package alongside its stimulant effects.
[19:11 –> 19:49] Now compare these with many modern energy drinks. They deliver caffeine, but usually without the natural polyphenol package. Instead, they often contain synthetic additives, amino acids like taurine, herbal extracts like guarana and yohimbine, high doses of B vitamins, and large amounts of sugar. Studies have shown that energy drinks can increase blood pressure more than other caffeinated beverages and lengthen the QTc interval on an EKG, which at extremes can predispose to arrhythmias. And regular consumption of sugar sweetened beverages has been associated with higher all cause and cardiovascular mortality.
[19:49 –> 20:18] So it’s important to take note here that it’s not just caffeine that matters, but the company it keeps. Coffee, tea, cocoa, mate, they bring caffeine wrapped in complex polyphenol packages that appear to contribute much of the long term health benefits. Energy drinks, in contrast, often strip caffeine of those natural partners and combine it with added sugars and stimulants that may carry their own risks, and I generally don’t recommend them. So what about the downsides to caffeine? That’s something we haven’t talked about yet.
[20:18 –> 20:31] Because there are always trade offs. Nothing in the world is free, and caffeine is no exception. The most important downside for most people is its effect on sleep. Remember, caffeine blocks adenosine receptors. That lowers sleep pressure.
[20:31 –> 20:58] If you drink caffeine too close to bedtime, you are essentially churning off that signal that tells your brain it’s time to rest. Control studies show this clearly. A four hundred milligram dose of caffeine taken at bedtime, three hours before bed, or even six hours before bed shortens total sleep time and fragments sleep throughout the night. EEG recordings, which are brainwave recordings, also show a reduction in slow wave delta sleep. That’s the deep restorative sleep stage.
[20:58 –> 21:21] Because caffeine has a half life of about three to seven hours, a practical rule of thumb is to stop consuming caffeine eight to ten hours before bed. For many people, that cutoff is just enough, But some people are fast metabolizers. They clear caffeine more quickly. And some are slow metabolizers, holding onto it for much longer. Let me share an example from my own life.
[21:21 –> 21:42] For a while, I was waking up at 2AM every night. I would feel restless, anxious, and have a headache. I tried everything, cooling sheets, meditation, magnesium, supplements, not eating late, but nothing worked. I assumed caffeine was the culprit, so I stopped drinking caffeine in the afternoon, and that didn’t help. Then I wondered, could this be caffeine withdrawal waking me up?
[21:42 –> 22:01] I tried an experiment. I had a cup of coffee at 5PM, which most people would think is a recipe for disaster. That night, I slept like a baby, and this pattern repeated. If I had coffee in the late afternoon, I slept fine. If my last cup was around one or 2PM, I woke up at 2AM feeling terrible.
[22:01 –> 22:18] Why was this happening? It turns out I’m a fast metabolizer. By the time 2AM rolled around, I had burned through my caffeine stores and was already in withdrawal. That withdrawal was waking me up. So if you find yourself waking in the middle of the night, it may not always be because of caffeine interfering with sleep.
[22:18 –> 22:38] In some people, it could be the opposite, caffeine withdrawal. If you suspect that’s the case, you have two choices. One is to have a small cup of coffee later in the day, which pushes withdrawal into the morning hours when you’ll have your first cup anyway. The other is to quit caffeine entirely. Go through the withdrawal period once and free yourself from it altogether.
[22:38 –> 22:58] Okay. Let’s get back to the other downsides of caffeine. One clear area is blood pressure. For most people, moderate coffee intake is associated with a lower cardiovascular mortality. But in people with severe hypertension, that’s grade two or grade three hypertension, the kind that is very difficult to control medication, the story looks completely different.
[22:58 –> 23:32] A Japanese cohort study found that drinking more than two cups of coffee in this group was linked with about a double risk of cardiovascular mortality. So if your blood pressure is consistently in the one sixty over one hundreds or greater, coffee is not your friend, and energy drinks are definitely off the table. Caffeine can also trigger anxiety and palpitations, especially in people who are already prone to anxiety disorders or panic attacks. That overstimulation comes from the same neurostimulant effects that give other people focus and motivation. Energy drinks are even more concerning in this area.
[23:32 –> 23:54] They contain caffeine, but also other additives that amplify electrical effects in the heart. Compared to coffee, they cause stronger increases in blood pressure and can lengthen the QTc interval on EKGs, which raises the risk of dangerous arrhythmias. Reflux is another issue. Caffeine relaxes the lower esophageal sphincter. That’s the valve at the bottom of your esophagus.
[23:54 –> 24:13] If that valve loosens, acid can wash up into your esophagus, causing symptoms of GERD. The picture is complex, though. For example, tea reliably gives me reflux, but coffee does not. So this effect may vary depending on the drink and the individual. Pregnancy is another time when caffeine needs extra caution.
[24:14 –> 24:43] Systematic reviews have linked maternal caffeine intake to dose dependent increases in low birth weight and fetal growth restriction. And some studies also report higher miscarriage rates. These are only associations, but they’re concerning enough that many authorities recommend a limit of two hundred milligrams per day during pregnancy. And it’s important to note that during pregnancy, caffeine metabolism slows down. Its half life gets much longer, so it lingers in the body.
[24:43 –> 25:06] My thought on this one is simple. If you don’t need a chemical input during pregnancy, whether that’s caffeine or any other drug, just avoid it. And then finally, we should talk about withdrawal because it’s real and it’s a downside to caffeine. When you stop caffeine, you may feel headaches, fatigue, irritability, and poor concentration. Symptoms usually start twelve to twenty four hours after your last dose.
[25:06 –> 25:23] They peak in about two days and can last up to nine days. Quitting caffeine is absolutely possible. I’ve done it several times. Within a week or so, you feel normal again. But for me, the motivational and productivity benefits are so strong and useful that I’ve chosen to keep caffeine in my life.
[25:23 –> 25:45] Then there’s one more topic that comes up all the time in media, and that’s mold toxins in coffee. So what are people talking about? When certain fungi grow on crops or during fermentation, they can produce compounds called mycotoxins. The one most relevant to coffee is ochratoxin a. The European Union has set a maximum limit for roasted coffee of five micrograms per kilogram.
[25:45 –> 26:12] Most commercially available coffees test well below that. Analysis typically show levels around two or three micrograms per kilogram, which is comfortably under regulatory limits. Now that doesn’t mean we want any amount of fungal toxin in our food, but it’s important to keep perspective. Coffee is actually a very small contributor to daily ochratoxin exposure. Grains, dried fruits, wine, and other fermented foods make up the majority of the intake in most diets.
[26:12 –> 26:49] If you wanna buy coffee that is certified mycotoxin and mold free, that’s reasonable. I’ve tried it myself, but to be honest, I’ve never noticed a physical difference between high quality coffees labeled as mycotoxin free or mold free versus other high quality coffees. Modern processing like roasting already reduces most of the opotoxin load. So if you do choose mold free or mycotoxin free coffee, check what they’re actually testing for, what limits they use, and compare that with your overall diet. If you’re eating grains, drinking wine, or consuming other fermented foods, those sources likely contribute much more to your exposure than coffee does.
[26:49 –> 27:16] Focusing only on coffee may not be the biggest yield. Okay. And there’s one more idea you may have heard of popularized in social media that you should wait ninety to a hundred and twenty minutes after waking before drinking coffee or any other caffeinated beverage. The claim is that caffeine consumption in that window worsens your morning cortisol surge and that delaying your first cup will prevent an afternoon crash. So let’s take a closer look at that.
[27:16 –> 27:51] The cortisol awakening response is the natural rise in cortisol that peaks about thirty to forty five minutes after you wake. Caffeine can nudge cortisol up even more in that period, but so can a morning workout. Neither caffeine or working out in the morning has been shown to create a later crash, and there are no trials showing that delaying coffee improves outcome compared with drinking it upon waking. The other part of the rationale behind this wait to caffeinate ideology is that you should let leftover adenosine clear before you block receptors with caffeine. But adenosine does not sit in a reservoir.
[27:51 –> 28:23] It’s produced and cleared continuously. When we give adenosine in the hospital for arrhythmias like supraventricular tachycardia, it disappears from the bloodstream in under ten seconds, which tells you the system is built for rapid turnover. In the brain, extracellular adenosine rises with wakefulness and falls with sleep, then begins rising again after you wake. There’s no pool of adenosine to wash out. So if the biochemistry does not support the claim that you should wait before consuming caffeine in the morning, what explains this afternoon dip that some people feel?
[28:23 –> 28:42] Two concepts cover most of it. First, the normal early afternoon circadian dip that happens even without caffeine. This is just a normal part of human biology, and we can objectively track it with core body temperatures. This is likely the number one reason that people feel so tired shortly after lunch. Second reason is simple pharmacokinetics.
[28:42 –> 29:07] A morning caffeine dose may be wearing off by early afternoon, especially if you’re a fast metabolizer. So the best available evidence does not support delaying morning caffeine to prevent a crash. And studies show that caffeine right after waking can reduce sleep inertia and improve vigilance when you need to be sharp. With all that said, try it yourself. Try drinking your morning coffee a little later.
[29:07 –> 29:25] If you feel better holding off for an hour or two, that’s fine. You don’t need a randomized controlled trial to justify your routine. Biochemically though, there’s no strong reason to delay your first cup. And if your morning demands focus, having coffee on waking is a reasonable, evidence supported choice. So let’s summarize.
[29:25 –> 30:08] I’ve given you a lot of information about caffeine. We talked about where it comes from, what it does, and how it potentiates motivation, movement, concentration, and memory in the brain, how it’s not a dopamine releaser like many addictive drugs, but instead a dopamine potentiator, which means it allows your natural dopamine to better activate the motivational and functional machinery of your mind and body so you can accomplish more. And another interesting thing about caffeine is that it rarely comes alone. In coffee, tea, cacao, and yerba mate, it’s packaged with polyphenol rich compounds that carry their own health promoting effects from better blood pressure control to improved blood sugar, vascular health, and even cognitive function. We also talked about how much is safe.
[30:08 –> 30:48] For most adults, about four hundred milligrams per day is considered safe, but people are all different. For some, four hundred milligrams might be too much, and for some, four hundred milligrams might not touch you. That’s why you need to use common sense and biofeedback to determine what doses of caffeine work best for you. When it comes to sleep, a practical rule is to leave eight to ten hours buffer between your last caffeine and bedtime, longer if you metabolize caffeine slowly and shorter if you’re like me and metabolize it crazy fast. Remember, I discovered that I was waking up at 02:00 every morning from caffeine withdrawals, and drinking caffeine later actually helped me sleep better through the night.
[30:48 –> 31:36] And if you find yourself dipping in the early afternoon, just realize that this is a normal part of the circadian mid afternoon dip that’s very common in human biology. You can try abstaining from caffeine for the first couple hours in the morning to see if this helps, but oftentimes, just redosing with caffeine in the afternoon is your ticket to alertness. And if you’re looking at physical performance, the best supported dose is three to six milligrams per kilogram taken about an hour before training or competition. The people who should really avoid caffeine are those with severe uncontrolled hypertension, say blood pressure in the one sixties over one hundreds, and pregnant women who should weigh the risks and keep intake moderate if they choose to drink it at all. If you’re prone to anxiety, tea can sometimes be easier to tolerate because of the balancing effects of l theanine.
[31:36 –> 32:05] If reflux is an issue, try a different package for your caffeine, like cacao, tea, mate. Often, it’s not the caffeine, but some compound that’s packaged with the caffeine that’s actually causing your problem. Or if you keep having reflux, just ditch caffeine altogether. We also covered how caffeine can enhance pain relief, Adding about a hundred to two hundred milligrams to standard medications like acetaminophen or ibuprofen improves relief for more people. If you’re planning to just quit caffeine altogether, it is actually doable.
[32:05 –> 32:28] Every time I’ve done it, I’ve just quit cold turkey, and I was fine. Maybe I was a little irritable, but that’s about it. But if the caffeine withdrawal causes you significant irritability or headaches, then tapering slowly by cutting back about fifty to a hundred milligrams every few days is fairly gentle. By the end of the week, you should be over it and caffeine free. So I hope I’ve given you the information to understand caffeine better.
[32:28 –> 32:46] I personally don’t place it anywhere near nicotine and other addictive drugs. Nicotine hijacks your mind in a way that makes it almost impossible to live without. Caffeine does have addictive qualities, but it’s a potentiator. It helps you get into your best motivated and active state. And anyone who drinks coffee or tea knows this.
[32:46 –> 32:58] Its effects are reliable, reproducible, and effective. So now that you have all the facts, you decide what you wanna do with them. Should caffeine be a part of your life? Do the benefits outweigh the risks? Well, for me, they do.
[32:58 –> 33:28] For you, maybe they won’t. But either way, I hope this empowers you to make the decision yourself and to possibly use caffeine deliberately in a way that supports your health and your goals. Okay. In our next episode, we’ll head back to tribulations where I’ll tell the story of how a tin bowl, a sack of salt, and a paper cone of sugar ended up leading to the saving of countless children’s lives. This is the story of how oral rehydration solutions became one of the greatest medical advances of our time.
[33:28 –> 33:37] It’s a story you won’t wanna miss and one you can use in your everyday life. And until next time, stay curious, stay critical, and stay healthy. Cheers.