Episode 9: The Vitamin C Paradox

Support Gavin’s Journey

Episode Highlights

Lost Enzyme, Hidden Deficiency: Why humans—and only a handful of other species—can’t make vitamin C, and how this sets us up for deficiency.
The Recycling Edge: How human red blood cells act as mobile vitamin C “rechargers,” and what it means for dosing.
Scurvy Isn’t History: Why mild vitamin C deficiency is shockingly common (even in the U.S.) and how it shows up today.
The Gavin Miracle: How one young boy’s family used IV vitamin C when all hope was lost—and what happened next.
Clinical Truths & Myths: What landmark studies and real-world evidence say about vitamin C for colds, gout, heart disease, and cancer.
Practical Supplement Tips: Plain, buffered, liposomal, or IV? How to pick what’s right for you.
Dose for Health (Not Just Survival): Why the RDA is just the starting line, and how to personalize your intake for stress, sickness, and recovery.

Show Notes

In this episode, Dr. Ravi Kumar takes you on a deep dive into vitamin C—from ancient evolutionary biology to cutting-edge integrative medicine. Learn why most animals never worry about vitamin C (and why you have to), how our bodies evolved “backups” like uric acid retention and red blood cell recycling, and why even modern diets leave many people running on empty.

Dr. Kumar covers:

The biochemistry of ascorbic acid: its roles as a master antioxidant, immune booster, collagen builder, neurotransmitter cofactor, and more.
The realities of deficiency: from ancient scurvy to modern subclinical cases.
Optimal intake: What traditional diets, primates, and the latest research say about how much you really need.
The clinical controversy: Why many trials miss the real benefit of vitamin C, and what meta-analyses reveal about colds, infections, and chronic disease.
Supplement science: How to choose the right form, spread your intake, and use vitamin C strategically during illness or stress.
High-dose & IV vitamin C: Why delivery matters—and the story of Gavin, a boy with a terminal brain tumor whose recovery with IV vitamin C defied all expectations.

Don’t miss:

A practical “tiered” vitamin C dosing guide for daily health, illness, and critical care.
Why Dr. Kumar personally includes vitamin C in his family’s daily routine—and would use IV vitamin C in any integrative cancer plan.

Gavin’s Story

When Gavin was diagnosed with a devastating brain cancer, his family searched for hope beyond the standard playbook. Their choice to pursue high-dose IV vitamin C, even when doctors had nothing left to offer, led to a recovery that inspired this episode—and Dr. Kumar’s evolving approach to integrative health.

Practical Recommendations

For daily health: 500–1,000 mg ascorbic acid, plus vitamin C–rich foods.
During stress/illness: Up to 6,000 mg per day, divided (and stay well hydrated).
Cancer/critical care: Discuss IV vitamin C as an adjunct with your doctor.
Supplements: Plain ascorbic acid is most cost-effective; buffered or liposomal forms may help sensitive stomachs.

Support the Show

If you found this episode valuable, please:

Share it with someone you care about
Leave a rating or review on your podcast app
Subscribe for future episodes
Visit DrKumarDiscovery.com for blogs, transcripts, and more
Follow me on Instagram and Facebook

Transcript

00:00:00.000 –> 00:00:32.900
This week on the Dr. Kumar Discovery Podcast. Vitamin C is absolutely essential for our biology. ^[1] Yet the way we’ve evolved to depend on it is actually pretty out of sync with how most of us live today. All this suggests that our own biology may be set up to handle and possibly benefit from much higher levels of vitamin C than what we typically see in the modern diet. ^[9], ^[10] Vitamin C is one of those rare nutrients that is cheap, safe, and almost universally under consumed. ^[2] It may be the lowest hanging fruit in human health optimization.

00:00:33.940 –> 00:00:57.910
My name is Dr. 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.

00:00:58.150 –> 00:01:14.465
Let us question everything and discover our true potentials. Welcome to the Dr. Kumar Discovery. My name is Dr. Ravi Kumar. I’m a board certified neurosurgeon and an assistant professor of neurosurgery at UNC.

00:01:14.465 –> 00:01:32.730
You are listening to the Dr. Kumar Discovery podcast. My goal here is simple, to cut through medical dogma and bias and bring real clarity to complex health issues. I wanna question everything, not just for my own understanding, but for yours as well. So thanks for joining me. Today, we’re diving into vitamin C—and by the end of this episode, you’ll have clear practical guidelines for optimizing your vitamin C intake, what you need day to day, and what to consider during stress or illness, and even some insights into its role in advanced treatments like cancer. ^[6], ^[7], ^[8]

00:01:32.730 –> 00:01:41.545
Now I know what you’re probably thinking. Vitamin C? Really? Isn’t that old news? It’s in oranges, orange juice, and those Flintstone vitamins we grew up with.

00:01:41.545 –> 00:02:08.255
Why dedicate a whole episode to it? Well, here’s why. Vitamin C is absolutely essential for our biology, yet the way we’ve evolved to depend on it is actually pretty out of sync with how most of us live today. By the end of this episode, you’ll have clear practical guidelines for optimizing your vitamin C intake—what you need day to day, what to consider during stress or illness, and even some insights into its role in advanced treatments like cancer.

00:02:08.255 –> 00:02:33.595
And just a quick disclaimer. Before we dive in, I’m a doctor, but I’m not your doctor. This podcast is for informational purposes only and isn’t meant to diagnose or treat any medical condition. My aim here is to bring clarity to complex health topics so you can think more clearly about your health and make informed decisions with your health care provider. I believe knowledge is power, and I want to empower you to take an active role in your health journey.

00:02:33.675 –> 00:02:54.530
Also, please note that this podcast is separate from my role as an assistant professor at UNC. So let’s get started with the most basic question. What is vitamin C? Chemically, vitamin C is called ascorbic acid. It’s a powerful antioxidant—a molecule that helps neutralize free radicals, which are unstable molecules that can cause oxidative damage in our bodies. ^[2]

00:02:54.665 –> 00:03:18.750
What’s interesting about ascorbic acid is how universal it is across life on Earth. It’s been highly conserved throughout evolution, showing up in almost every form of life. But two major kingdoms rely on it the most, kingdom Plantae and kingdom Animaliae. Plants make vitamin C to help manage the intense oxidative stress created by photosynthesis. Think of photosynthesis as a controlled fire. It’s essential for life, but if it gets out of hand, it can damage the plant. So the plants use vitamin C to keep things in balance, and it’s found throughout all their tissues.

00:03:18.750 –> 00:03:45.440
Most animals also make their own vitamin C using an enzyme called L-gulonolactone oxidase. This enzyme allows them to convert glucose into vitamin C whenever they need it, supporting their antioxidant defenses and many other bodily functions. But here’s where it gets interesting for us. Humans, along with a handful of other species like higher primates, guinea pigs, some bats, and certain fish, have lost the ability to make vitamin C because of mutations in this enzyme. ^[11]

00:03:45.520 –> 00:04:14.190
So unlike most animals, we can’t make our own vitamin C and we have to get it entirely from our diet. In almost every case, that means we depend on plants to provide our vitamin C, and that sets the stage for everything else we’re going to talk about in this podcast.

00:04:14.350 –> 00:04:36.240
But what makes vitamin C so special? Why has evolution preserved it so widely across such different life forms? The answer to that question is twofold. First, vitamin C is water soluble, which means it dissolves easily in the fluids of our bodies. This allows it to circulate freely in our blood and reach every cell in our body. In addition, it has the ability to diffuse oxidative damage in lipid membranes, which is usually the domain of fat soluble antioxidants. That makes vitamin C uniquely able to provide constant antioxidant protection in all the watery and fatty spaces of our bodies.

00:04:36.240 –> 00:05:01.050
Second, vitamin C is a powerful and fast-acting antioxidant. Here’s what that means. When free radicals start a chain reaction, they can cause damage by bouncing from molecule to molecule, lighting up a sort of molecular wildfire. Vitamin C is like a firefighter. It jumps in and neutralizes the free radicals and stops the chain reaction in its tracks. What’s even more impressive is that vitamin C doesn’t just get used up once. After it neutralizes a free radical, it can be recycled, essentially recharged, so it can go right back to work again and again. ^[12]

00:05:01.210 –> 00:05:28.415
This makes it incredibly efficient at controlling oxidative stress over time. So you’re probably asking, what do I mean by oxidative stress? In simple terms, oxidation is when a molecule loses an electron, and reduction is when it gains one. We collectively call these redox reactions, and they power almost every process in our bodies—energy production, building proteins, creating DNA, and much more. ^[13], ^[14]

00:05:28.700 –> 00:05:52.365
Oxidation is like the spark that keeps our biological engines running. But just like a fire, it needs to be controlled. If oxidation gets out of hand, it can damage important parts of our cells. It can oxidize fats in our cell membranes. It can change the shape of our proteins causing them to malfunction, and it can damage DNA causing mutations.

00:05:52.525 –> 00:06:12.180
Unchecked oxidative stress is at the root of many diseases—aging, cognitive decline, Alzheimer’s disease, cardiovascular disease, high blood pressure, metabolic diseases like diabetes, and even cancer. These chronic inflammatory diseases are almost always associated with runaway oxidative damage. That’s why antioxidants are so important and why vitamin C is a keystone molecule in this system.

00:06:12.655 –> 00:06:49.275
Now to really understand how vitamin C works, we need to look at its structure and how it acts at the chemical level. In its active form, vitamin C is called ascorbate. Think of ascorbate as a tiny battery always ready to donate an electron to a molecule that has become oxidized. Remember, when a molecule is oxidized, it’s lost an electron, and giving it back an electron neutralizes it or reduces it. Ascorbate steps in, offering one of its electrons along with a proton to this oxidized molecule. That stabilizes the molecule and stops the damage from spreading.

00:06:49.275 –> 00:07:19.705
At this point, vitamin C itself is missing an electron. Normally, a molecule in this state would go looking for an electron to steal, which can keep the cycle of damage going. But vitamin C does something unusual. Instead of becoming a problem itself, it actually is able to give away a second electron to another oxidized molecule. By doing this, vitamin C ends up neutralizing two free radicals instead of just one and prevents the runaway free radical chain reaction that leads to cell and tissue damage.

00:07:19.785 –> 00:07:42.915
After giving away those two electrons, vitamin C becomes dehydroascorbate, an oxidized form that’s pretty stable. Most molecules in this state would become reactive and start causing trouble, but dehydroascorbate doesn’t. That’s because of its unique chemical structure.

00:07:43.075 –> 00:08:11.865
Now this is where our bodies get clever. Dehydroascorbate enters something called the glutathione-ascorbate cycle. Glutathione steps in to restore vitamin C by donating electrons back to it, turning it from dehydroascorbate back into its active form ascorbate. This recycling process relies on an enzyme called glutathione reductase and a little help from a molecule called NADPH, which we use for energy production systems. ^[21]

00:08:11.865 –> 00:08:52.100
So as long as our cells have enough energy, this cycle keeps vitamin C recharged and ready to fight oxidative stress over and over again. It’s a remarkable built-in defense system with vitamin C and glutathione working together to constantly protect ourselves from damage.

00:08:52.100 –> 00:09:13.360
Hey there. I hope you’re enjoying the show, and thanks for being here. If you’re finding this valuable, I have a small favor to ask. Please share this episode with someone who you think would benefit from clear, practical health information. In a world full of confusing and conflicting advice, getting evidence-based, understandable insights out there really matters, and you can help make that happen.

00:09:13.360 –> 00:09:23.760
Also, if you have a moment, please leave a quick rating or review on your podcast app. It really helps others find the show. I’m grateful you’re here. Thanks for listening, and let’s get back to it. Okay.

00:09:23.760 –> 00:09:48.260
We’ve explored just how remarkable vitamin C is and how it works. Let’s get back to why we actually need to consume it. Most animals don’t have to worry about getting vitamin C from their diet because they make it themselves. They use an enzyme called L-gulonolactone oxidase to turn glucose into vitamin C right inside their bodies. But about sixty-one million years ago, our primate ancestors lost this ability. ^[17]

00:09:48.420 –> 00:10:16.040
Back then, their diets were so rich in vitamin C, mainly from plants and fruits, that there was no pressure to keep this enzyme working. Over time, mutations built up in this gene. And because they didn’t need the enzyme, there were no consequences. In fact, there might have even been evolutionary advantage to dropping a complex metabolic system that was no longer needed. We actually still have that gene for this enzyme in our DNA today, but it’s so mutated it no longer works.

00:10:16.040 –> 00:10:45.030
Consequently, just like our primate ancestors, we now have to get all of our vitamin C from food, mostly from plants. That’s in stark contrast to animals like ruminants and rodents, which still have a working enzyme. They can make plenty of vitamin C whenever they need it, helping them keep their immune system strong, their antioxidant defenses active, and their collagen production steady without having to rely on diet alone.

00:10:45.030 –> 00:11:08.940
And there’s another important point here. Vitamin C, as we know, is water soluble. This gives it a big advantage. It can move freely through our blood and inside our cells, offering antioxidant protection wherever it’s needed. But that same property makes it easy to lose. Unlike fat soluble vitamins which can be stored in our fatty tissues for later use, water soluble vitamins like vitamin C are used up quickly and whatever’s left over is lost in our urine. ^[18]

00:11:08.940 –> 00:11:35.210
We don’t have a big reserve tank for vitamin C. It’s more like having just enough money for today’s needs. You have to replenish vitamin C regularly or you’ll run out. Now because we lost the ability to make our own vitamin C and because of its transient nature in our biology, our bodies had to adapt some pretty creative ways to survive periods when vitamin C wasn’t always available. One of these adaptations is higher levels of plasma uric acid.

00:11:35.210 –> 00:12:03.255
Uric acid is a natural waste product that forms when we break down purines—these are substances found in many foods and produced by our own cells. Normally, we just pee out uric acid, treating it as a waste product. But uric acid is actually a pretty strong antioxidant at moderate or low levels, able to neutralize free radicals much like vitamin C. ^[15]

00:12:03.400 –> 00:12:31.780
When our vitamin C levels drop, our bodies become even more efficient at keeping uric acid in the bloodstream. The transporter in our kidneys that naturally reabsorbs vitamin C is called SVCT1. It will start pulling in uric acid instead when vitamin C is super low. This system helped our ancestors maintain some level of antioxidant defense during times of vitamin C deficiency. But there’s a downside.

00:12:31.860 –> 00:12:57.705
In the modern world, we eat a lot of foods high in purines, and at the same time, many people are still not getting enough vitamin C. This can lead to elevated uric acid levels in the blood, which crystallizes in the joints and tissues causing pain and inflammation—a condition known as gout. ^[69]

00:12:58.070 –> 00:13:20.075
Another unique adaptation is how our red blood cells have become mobile recycling centers for vitamin C. To put this in perspective, you have about 25 000 000 000 000 red blood cells circulating in your body at any moment. They’re by far the most common cells in your body, making up about 70 percent of all of your cells. Red blood cells are simple in design.

00:13:20.075 –> 00:13:51.965
They don’t have a nucleus or mitochondria, and they only live about 120 days. Their main job is to carry oxygen, but they also play a key role in vitamin C recycling. Here’s how it works. In most animals, red blood cells use a glucose transporter called GLUT4. But in humans and other species that can’t make vitamin C, we use GLUT1. ^[20]

00:13:52.125 –> 00:14:29.850
GLUT1 pairs with a molecule called stomatin to bring spent, oxidized form of vitamin C, dehydroascorbate, into the red blood cell. Inside, there’s a large supply of glutathione and NADPH—both needed for the glutathione-ascorbate cycle we talked about earlier. This allows red blood cells to rapidly recycle vitamin C, restoring it to its active form. ^[22]

00:14:29.930 –> 00:15:03.440
But it doesn’t stop there. The recycled vitamin C can pass electrons to other vitamin C molecules in the bloodstream, creating a kind of ongoing recycling system. You can think of your red blood cells as tiny charging docks. Just like plugging your phone into a charger, spent vitamin C plugs into the red blood cells, gets recharged, and is sent back out to do its job again.

00:15:03.645 –> 00:15:42.455
This super efficient recycling system means we need about 100 times less vitamin C than animals that don’t have this adaptation. Instead of needing something like 20 000 mg a day of vitamin C, we can get by with as little as 200 mg, thanks to this high-speed recycling system in our red blood cells. ^[23]

00:15:42.535 –> 00:16:06.305
One more critical adaptation in hominids who lost the L-gulonolactone oxidase gene involves our stress hormone system. Vitamin C is used throughout the animal kingdom as a stress management molecule. When an animal is stressed, they make vitamin C to cope with the biological strain of heavy stress. Humans unable to make vitamin C and with deficient diets compensate by producing higher levels of cortisol during acute stress.

00:16:06.385 –> 00:16:41.495
Vitamin C stimulates the production and function of white blood cells, the body’s main line of defense against infection. ^[30], ^[23]

00:16:41.575 –> 00:17:21.450
Vitamin C is also required for synthesis of carnitine, a molecule that shuttles fatty acids into our mitochondria for energy production. ^[5] Without enough vitamin C, carnitine production drops and so does our ability to generate cellular energy.

00:17:21.450 –> 00:17:54.890
When it comes to neurotransmitters, vitamin C is just as vital. It donates an electron to dopamine beta-hydroxylase, the enzyme that converts dopamine to norepinephrine. ^[4] Without enough vitamin C, norepinephrine production drops which can lead to fatigue, low blood pressure and poor stress tolerance.

00:17:55.175 –> 00:18:30.795
Vitamin C is also required to recycle tetrahydrobiopterin, a molecule needed to make neurotransmitters and to enable nitric oxide production, which relaxes our blood vessels and maintains healthy circulation. ^[27]

00:18:30.795 –> 00:19:07.660
Another critical function is iron absorption, especially for people who get most of their iron from plants. Animal-sourced iron (heme iron) is readily absorbed. But plant-based non-heme iron, like that in spinach, is hard to absorb unless vitamin C is present. ^[28]

00:19:07.740 –> 00:19:37.550
Vitamin C also helps counteract natural compounds in plants like phytates and polyphenols that inhibit nutrient absorption. ^[29]

00:19:37.550 –> 00:20:15.565
So vitamin C isn’t just an antioxidant. It’s absolutely essential for immune defense, tissue strength, neurotransmitter production, blood vessel health, nutrient absorption, and much more. Without enough vitamin C, almost every part of our biology starts to break down.

00:20:15.565 –> 00:20:36.790
Now that we know what vitamin C does, it’s important to understand what happens when we don’t get enough. The classic disease of vitamin C deficiency is called scurvy, also called the scourge of the sea by sailors because of the miserable death it produced. ^[36], ^[37]

00:20:36.790 –> 00:21:08.180
Early signs—fatigue, irritability, muscle pain, joint pain, and loss of appetite—are nonspecific. As deficiency progresses, bleeding and swollen gums, loose teeth, easy bruising, slow wound healing, corkscrew hairs, joint pain, and frequent infections appear. If left untreated, scurvy leads to severe anemia, internal bleeding, organ failure, and death.

00:21:08.180 –> 00:21:34.880
Scurvy symptoms usually appear about two to three months after vitamin C disappears from the diet. This timing lines up with the turnover of red blood cells, our internal vitamin C reservoirs. The good news is scurvy is easily treated—just add vitamin C back into the diet and symptoms resolve within weeks.

00:21:34.960 –> 00:22:16.925
Scurvy was known in ancient Egypt (c. 1550 BC) and famously cured in 1747 when Scottish naval surgeon James Lind conducted one of the first controlled trials aboard HMS Salisbury. He divided 12 sailors with scurvy into six groups and found only the group given citrus fruits recovered. ^[38], ^[39]

00:22:16.925 –> 00:22:44.825
Later, lemon and lime juice rations became compulsory for sailors—hence “limeys.” Scurvy also struck during the Irish Potato Famine, polar expeditions, the US Civil War, and the California Gold Rush. ^[40], ^[37]

00:22:44.905 –> 00:23:21.690
A breakthrough came in 1928 when Albert Szent-Györgyi isolated vitamin C (then called hexuronic acid) from adrenal glands, later renamed ascorbic acid. He shared the 1937 Nobel Prize with Sir Walter Norman Haworth for elucidating its structure and function. ^[41], ^[42]

00:23:21.690 –> 00:24:03.450
Surprisingly, vitamin C deficiency remains common even today, sometimes as subclinical scurvy. Large surveys show deficient levels across the globe—including UK, Canada, Mexico, India, and the US. In the US, about 15 percent of adults are vitamin C deficient and up to 20 percent have depleted levels. ^[43], ^[44], ^[45], ^[46], ^[47], ^[48], ^[49]

00:24:03.825 –> 00:24:39.585
Current guidelines from the US Institute of Medicine recommend 90 mg/day for men and 75 mg/day for women—just enough to prevent scurvy. These RDAs are based on the estimated average requirement (10–60 mg/day) plus two standard deviations. ^[50], ^[51] But this RDA prevents scurvy—it may not optimize health.

00:24:39.585 –> 00:24:58.440
To find optimal dosing, it helps to look at animals that still make vitamin C. Goats (70 kg) synthesize ~13 g/day. ^[52] Rodents make 80–300 mg/kg/day, up to ~21 g/day for a 70 kg animal. ^[53] These production rates—150–300× our RDA—reflect roles in stress, infection, tissue repair.

00:24:58.545 –> 00:25:29.045
Wild primates (our closest cousins) get large amounts from diet. Howler monkeys eat ~90 mg/kg/day (~7.2 g/day for an 80 kg human—^[24], ^[54], ^[55]).

00:25:29.045 –> 00:26:01.015
Spider monkeys get ~100 mg/kg/day, gorillas 20–30 mg/kg/day (~3–6 g/day). These high intakes likely reflect evolutionary pressure for antioxidant defense, strong immunity, and rapid repair.

00:26:01.015 –> 00:26:40.510
So how much Vitamin C do modern humans actually get? US adults average 75–100 mg/day from food (no supplements). ^[49], ^[48]

00:26:40.590 –> 00:27:30.230
Traditional hunter-gatherers like the !Kung and Hadza average ~500 mg/day from wild fruits and tubers. ^[24] Arctic Inuit—despite low plant intake—get ~200 mg/day from whale skin, seal skin, seaweed, fish eggs, and berries. ^{<a href="#ref-93" title=“Inuit “country foods” intake”>[93]}

00:27:30.230 –> 00:28:02.680
Next, how do we absorb and distribute Vitamin C? Intestinal absorption via SVCT1 rises steeply up to ~200 mg in a single dose, then plateaus between 200 mg–2.5 g. Plasma saturates at ~200 mg/day. ^[56], ^[57]

00:28:02.680 –> 00:28:38.060
Tissue uptake via SVCT2 concentrates Vitamin C in brain, pancreas, white cells—even when plasma doesn’t rise further. This two-phase system ensures high tissue stores despite plasma plateau.

00:28:38.425 –> 00:29:06.205
For a healthy person, 200 mg/day saturates plasma and tissues under low stress. But what about sickness or stress? Animals that make Vitamin C ramp up production when ill. Humans can’t—our needs spike instead. ^[58], ^[59], ^[60]

00:29:06.205 –> 00:29:47.960
Studies show white cell Vitamin C falls to scurvy levels within a day of cold symptoms, then recovers. To maintain normal immune-cell levels during illness requires up to 6 g/day for the first 3 days. ^[61]

00:29:48.040 –> 00:30:14.350
Another study found 500 mg/day maintained normal white-cell levels over 14 weeks in healthy adults. ^[94]

00:30:14.430 –> 00:30:42.990
Clinical trials confirm these findings. In one, students with colds took 6 g on day 1, then 3 g/day—symptoms dropped by 85 percent vs controls. Regular 600–1000 mg/day in athletes under heavy stress cut cold incidence by 50 percent. ^[66]

00:30:42.990 –> 00:31:30.365
A Cochrane review found regular Vitamin C reduced cold duration by 8 percent in adults and 14 percent in children, with greater benefit for severe colds. ICU respiratory-infection patients saw reduced stays and severity. ^[65], ^[62], ^[67]

00:31:30.525 –> 00:31:58.515
Despite these positive results, many RCTs use <1 g/day and enroll well-nourished subjects or run too short, biasing negative. Poorly designed RCTs often overshadow observational and mechanistic evidence. ^[79], ^[80]

00:31:58.515 –> 00:33:09.340
That said, well-designed RCTs do exist. A 2023 meta-analysis of 10 RCTs (>1 g/day) found adults shaved 8 percent off cold duration, children 14 percent—and people with worse colds saw larger benefits. ^[95]

00:33:09.340 –> 00:33:46.995
Large cohort studies show high vitamin C intake lowers gout risk by 45 percent (>1.5 g/day vs <250 mg/day) and each 500 mg/day increment cuts risk 17 percent. Supplementation lowers serum urate by 0.35 mg/dL. ^[69], ^[70], ^[71]

00:33:46.995 –> 00:34:09.610
In cardiovascular research, a 2012 meta-analysis (29 RCTs, ~500 mg/day) found systolic and diastolic BP reductions in hypertensive and normotensive subjects. ^[72]

00:34:09.610 –> 00:34:33.980
A 2014 trial showed decreased pulse wave velocity (better arterial compliance). Vitamin C supports nitric oxide production via BH₄ regeneration. ^[73], ^[75], ^[76]

00:34:33.980 –> 00:34:45.000
However, the Physicians’ Health Study II (500 mg/day) showed no CVD event reduction—likely too low dose and no stress dosing. ^[77]

00:34:45.000 –> 00:35:00.150
In sum, vitamin C supports immune defense, reduces gout risk, lowers BP, improves vascular function, and may reduce stroke risk—especially at doses exceeding the RDA.

00:35:00.310 –> 00:35:41.795
Next, let’s talk delivery forms. Most common is plain ascorbic acid—well absorbed, cost-effective, though mildly acidic. Buffered forms (sodium/calcium/magnesium ascorbates) are gentler but no more bioavailable. ^[94]

00:35:41.875 –> 00:36:13.445
Liposomal vitamin C packages ascorbic acid in lipid vesicles to bypass gut transporters, yielding ~20–30 percent higher plasma peaks—but tissues with SVCT2 transporters (white cells, brain, gonads) still rely on free ascorbate uptake. ^[96]

00:36:13.445 –> 00:36:31.870
Finally, IV vitamin C bypasses gut limits entirely, achieving blood levels up to ~70× oral maximum. This pro-oxidant surge targets cancer cells while sparing healthy cells. It’s explored as adjunct in oncology and critical illness. ^[97]

00:36:32.045 –> 00:37:10.525
Early in my career, I witnessed a toddler with leptomeningeal cancer recover dramatically on twice-weekly IV vitamin C infusions. He went from near-death to running and playing. His mother Raquel still gives him daily liposomal vitamin C. If I or a loved one faced cancer, I’d include IV vitamin C as adjunct therapy. ^[6], ^[86], ^[7], ^[87], ^[88]

00:37:10.760 –> 00:37:42.880
IV vitamin C also reduces fatigue via hormesis—brief oxidative spike triggers endogenous defenses. Trials show 10 g IV cuts fatigue at 2 h and 24 h. ^[89], ^[68]

00:37:43.040 –> 00:38:07.900
Risks of high-dose IV include oxalate nephropathy (kidney injury/stones)—rare—but screen susceptible patients. G6PD deficiency can trigger hemolysis—screen first. IV vitamin C may also interfere with some glucose meters. ^[91], ^[90], ^[92]

00:38:07.900 –> 00:38:39.730
Let’s review four dosing tiers:

Anti-scurvy: RDA (90 mg men, 75 mg women)—prevents scurvy but doesn’t optimize health.
Maintenance: ~200 mg/day to saturate plasma & tissues at rest.
Stress/illness: 500 mg/day prophylactic; up to 6 g/day during acute illness.
High-dose IV: pro-oxidant cancer/critical illness adjunct.

00:38:39.810 –> 00:39:15.920
My protocol: I take 500–1000 mg/day ascorbic acid, spread doses and eat vitamin C–rich fruits (oranges, kiwis, strawberries, mangoes). During colds, I ramp to 6 g/day divided. Hydration is key. I also use Vitamin D (“hammer dose”) at first cold symptom (see Episode 6). ^[50]

00:39:16.085 –> 00:39:56.005
If faced with cancer, I’d add IV vitamin C under medical supervision—low risk, potential high reward. You can contact Gavin’s mother Raquel via the links in show notes if you want to learn more.

00:39:56.220 –> 00:40:36.740
If you take one message from this episode: Vitamin C is cheap, safe, and almost universally underconsumed. It may be the lowest hanging fruit in human health optimization.

00:40:36.820 –> 00:41:16.595
In the next episode, we’ll talk about zinc—a companion nutrient essential for immune function, wound healing, inflammation, and hormone balance. Like vitamin C, zinc deficiency is much more common than most people realize.

00:41:16.990 –> 00:41:43.660
If you found this episode helpful, please share it with someone you care about and leave a review. I appreciate you listening. See you next time.

00:41:43.660 –> 00:42:19.420
Cheers.

Episode 9: The Vitamin C Paradox

Support Gavin’s Journey

Episode Highlights

Show Notes

Gavin’s Story

Practical Recommendations

Support the Show

Transcript

References & Resources

Disclaimer

Episode 9: The Vitamin C Paradox

Episode 9: The Vitamin C Paradox

Subscribe to the Podcast:

Support Gavin’s Journey

Episode Highlights

Show Notes

Gavin’s Story

Practical Recommendations

Subscribe & Follow

Support the Show

Transcript

References & Resources

Share this article

Join The Dr Kumar Discovery Community

Disclaimer