Show Notes
Go look at the ingredient list on whatever your kids ate this morning. The cereal, the yogurt, the vitamin gummy, even the toothpaste they spit into the sink. Odds are you will find a color that was synthesized in a chemical plant from crude oil.
In this episode, Dr. Ravi Kumar answers one question directly: are the synthetic chemicals entering our bodies every day harmful, or are they inert? He starts with where artificial colors actually come from, tracing the line from an accidental 1856 discovery by a young chemist trying to make a malaria drug, through a century of coal tar colors, to the petroleum derived azo dyes like Red 40, Yellow 5, and Blue 1 that sit in the American food supply today. These molecules add no nutrition and do nothing for shelf life or flavor. Their only job is to make a product look more appealing on the shelf, which changes the entire risk calculation.
He then takes on the behavior question, including the thing he had backwards for years. A 1995 JAMA meta analysis of controlled trials found that sugar does not affect children’s behavior or cognitive performance, even in kids whose parents were certain they were sugar sensitive. The randomized, double blind, placebo controlled trial published in The Lancet in 2007 out of the University of Southampton found something different: on the days children drank a mix of artificial colors plus a preservative, their measured hyperactivity went up. A 2021 review from California’s Office of Environmental Health Hazard Assessment reached the same conclusion across seven approved dyes and noted that the FDA’s safe intake levels were set decades ago using studies never designed to detect neurobehavioral effects.
From there the episode moves to preservatives: sodium benzoate, the one that rode along in the Southampton trial, and the synthetic antioxidants BHA, BHT, and TBHQ that keep fats from going rancid in cereals, chips, and chewing gum. BHA has been classified by the US National Toxicology Program as reasonably anticipated to be a human carcinogen since 1991 and listed under California’s Proposition 65 since 1990, and it has stayed in the food supply the whole time under a generally recognized as safe designation. The FDA only opened a formal reassessment of it in February 2026.
Dr. Kumar closes with the regulatory picture, including the January 2025 revocation of Red 3, the largely voluntary 2025 federal plan to phase out petroleum dyes by the end of 2026, Europe’s warning label requirement that has been in place since 2010, and the state level laws in West Virginia and California that are moving faster than the federal government. His conclusion is the precautionary principle: for a cosmetic chemical with zero nutritional upside, the question is not whether science has proved it harmful, but whether science has proved it safe.
Episode Resources
In this episode, you will discover:
- Where food coloring actually comes from: How Red 40 and its relatives are built from petroleum derived aromatic compounds in a chemical plant, and why they were called coal tar colors for a century
- The accidental origin story: How a young chemist chasing a malaria drug in 1856 ended up with a brilliant purple sludge and started the synthetic dye industry
- Why the dyes have no upside to weigh: They are not nutrients, they do not preserve, they do not improve taste. They exist to make the box look better, which changes the whole risk benefit calculation
- The sugar myth, dismantled: What the 1995 JAMA meta analysis found about sugar and children’s behavior, including in kids their own parents swore were sugar sensitive
- The trial that put this on the map: The 2007 University of Southampton study in The Lancet, a randomized double blind placebo controlled trial in 153 three-year-olds and 144 eight and nine-year-olds
- What the evidence does and does not say: Artificial dyes are linked to increased hyperactivity in some children, but they are not the cause of ADHD
- The preservative nobody talks about: Sodium benzoate, the survey data on ADHD symptoms in heavy consumers, and how it compares to the clinical trial evidence
- A carcinogen hiding under a safety label: BHA, called reasonably anticipated to be a human carcinogen since 1991, still in the food supply under GRAS, with an FDA reassessment finally opened in February 2026
- What is actually changing: The Red 3 revocation, the voluntary federal phase out plan, Europe’s warning label since 2010, and the state laws in West Virginia and California forcing national reformulation
- The precautionary principle: Why the burden of proof for a cosmetic food chemical should look more like the burden of proof for a new drug
- How to audit your own kitchen: The surprising places these additives hide, including children’s medicines and vitamins, toothpaste, flavored yogurt, bread, pickles, dressings, and microwave popcorn
Key Takeaways
- Artificial food colors are synthetic molecules derived from petroleum. They provide no nutrition, no preservation, and no flavor. Their only function is visual appeal
- Because there is no benefit on the other side of the scale, any nonzero risk is a bad trade. This is not a typical risk benefit calculation
- Sugar is not what changes children’s behavior. The controlled evidence does not support the sugar hypothesis, and Dr. Kumar had this backwards for years in his own family before testing it
- The controlled evidence does support a link between artificial colors plus preservatives and increased hyperactivity in children, established by the 2007 Southampton trial in The Lancet and supported by California’s 2021 review of seven approved dyes
- Artificial dyes do not cause ADHD. ADHD is multifactorial, and additives are best understood as one possible contributor among many
- BHA has been officially flagged by the US government’s own toxicology program since 1991 and is still in the food supply. The FDA opened a formal reassessment only in February 2026, with BHT next in line
- Europe has required a warning label on foods containing these colors since 2010. It is a label, not a ban, and the US has never required it. Honest labeling puts consumer pressure on industry without waiting for a federal ban
- States are moving faster than the federal government. Because manufacturers do not want separate formulations per state, a single state ban tends to reformulate the product nationwide
- The practical fix is simple even if it is not always easy: eat whole unprocessed food, read the ingredient list rather than the front of the package, and treat wholesome marketing claims as marketing
Transcript
[00:00 –> 01:12] Dr. Ravi Kumar: On this episode of the Dr Kumar Discovery, why is a petroleum derived chemical, one that adds zero nutrition and exists purely for looks, in our food in the first place? And do these chemicals harm us all? These dyes do nothing good for you. Their entire job is to make the product more visually appealing so you’ll buy it and your kids will want it. If you have a food that says, hey, this synthetic chemical may cause hyperactivity in your children, you’re much less likely to buy that product. The question should not be, Has the science proved it’s harmful yet? The actual question should be, Has science proven it’s safe? 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. Let us question everything and discover our true potentials. Welcome to the Dr Kumar Discovery.
[01:14 –> 01:49] Dr. Ravi Kumar: Welcome to the Dr Kumar Discovery. My name is Dr. Ravi Kumar. On today’s episode, we’re doing a deep dive on artificial colors, flavors, and preservatives in food. I wanna clearly answer this question. Are these synthetic chemicals that enter our bodies every day harmful or inert? So just to set the stage for how relevant this is, let me ask you something. Go look at the ingredient list on whatever you or your kids ate this morning. The cereal, the yogurt, the vitamin gummy, the toothpaste they spit into the sink.
[01:49 –> 02:42] Dr. Ravi Kumar: And on these labels, at least here in The US, you’re most likely gonna see a synthetic color like Red 40, Yellow 5, Blue 1. These are little molecules chemically synthesized from petroleum that are put in food for one reason, to make food look colorful and psychologically more appealing. So once you realize that these synthetic chemicals are in our food, the next question is, why is a petroleum derived chemical, one that adds zero nutrition and exists purely for looks, in our food in the first place, and do these chemicals harm us at all? So by the end of this episode, you’re gonna understand what these dyes actually are and where they come from. You’re gonna hear about how I still let my kids have sweets and no longer have to worry about hyperactivity due to a twist in the science that I completely had backwards for years.
[02:43 –> 03:53] Dr. Ravi Kumar: You’re gonna understand what the human evidence on behavior in children eating artificial colors really shows. We’re also gonna talk about artificial flavors and preservatives, including one preservative the US government has officially called a probable carcinogen for over 30 years, and it’s still in our food today. And then I’m gonna make my case for how we should actually think about food additives and whether or not they belong in our bodies in the first place. So one quick thing before we get into it, a disclaimer. I’m a doctor, but I’m not your doctor. This show is for informational purposes only. Everything I share today is meant to empower you. So take this knowledge, ask better questions, work with your doctor or your child’s pediatrician to build a more informed, healthier life. That’s what I want for you. And just to be clear, this show is also separate from my role as assistant professor at UNC. Alright. Let’s get into it. Let’s start with what artificial colors even are in the first place, because I think most people, myself included, for a long time, never really understood their origins. So take Red 40, the most common one. It’s not made from beets or berries or anything that ever grew in the ground.
[03:53 –> 04:57] Dr. Ravi Kumar: Red 40 is also called Allura Red, and it’s a synthetic chemical made in a chemical plant. It belongs to a family called azo dyes that are synthesized from crude oil. The starting materials are petroleum derived aromatic compounds that get run through a series of reactions until you get a bright, cheap, shelf stable red powder. And there’s actually a wild history here. The first synthetic dye was made by accident in 1856 by a young chemist named Perkins, who was trying to synthesize a malaria drug, and instead ended up with a brilliant purple sludge from coal tar. That’s the gunk that’s left over from processing coal. For about a century, these dyes that went into food and clothing and cosmetics were actually called coal tar colors. Today, we’ve switched the original substance from coal tar to petroleum, but the basic idea is the same. We are coloring food with molecules descended from the industrial chemistry that comes from these petroleum products. So here’s something that I mentioned earlier, but I think it’s important to emphasize.
[04:58 –> 06:09] Dr. Ravi Kumar: These dyes do nothing good for you. They’re not nutrients, they’re not preservatives, they don’t make food safer or last longer or taste better. Their entire job is to make the product more visually appealing so you’ll buy it and your kids will want it. That’s it. So when we get into the safety debate, keep that fact in the back of your mind because it changes the whole calculation. We’re not weighing a real benefit against a possible risk. There is no real benefit to having any of these dyes or chemicals in our food. Okay. So let’s start talking about what these chemicals might be doing to our bodies and our brains. I’ll start out with this personal story. When my kids would eat certain candies, the bright artificially colored stuff, my wife and I would see extreme hyperactivity, big emotional swings, and just completely atypical behavior for our normally sweet children. And like most parents, our first instinct was to say, well, it’s probably the sugar. They were getting too much sugar, and it was affecting their behavior. But at some point, I started asking if it wasn’t just a sugar problem. Because when my wife would bake sweets with all natural ingredients, we’d seen none of these wild behaviors in our kids.
[06:09 –> 07:15] Dr. Ravi Kumar: So we started buying naturally colored candies. And with the same kids eating the same amount of sugar but with dyes and artificial junks swapped out for natural fruit or vegetable extracts, our kids had no behavior changes. So the reaction we’d been blaming on sugar largely wasn’t there when they ate naturally colored sweets. So what does the literature say about this? Was I actually seeing something real, or was I just seeing what I wanted to see? Well, this is what the science says. There’s a meta analysis published in JAMA back in 1995 that pulled together the controlled double blinded studies on sugar and kids’ behavior. And the conclusion was that sugar does not actually affect the behavior or the cognitive performance of children. They even looked specifically at kids whose own parents swore that they were sugar sensitive, and they still found nothing. The authors made a fascinating point, which is that the strong parental belief that sugar causes hyperactivity was probably driven by expectation.
[07:16 –> 08:18] Dr. Ravi Kumar: We expect sugar to wind them up, so that’s what we see. And that’s what we saw for years until my wife and I ran our own personal experiment. The thing we changed wasn’t the sugar. We held the sugar roughly constant and pulled out the artificial colors and additives. And we saw no behavioral problems in our kids that we normally would have with artificially colored sweets. So if sugar is not the problem, does the literature support the idea that artificial colors change children’s behavior? Well, the answer is, yes, it does. The study that puts this whole topic on the map was published in The Lancet in 2007 out of the University of Southampton in The UK. And it was a randomized, double blind, placebo controlled trial, which is the gold standard for proving causation. They took 153 three-year-olds and 144 eight and nine-year-olds, and these were just kids from the general population, and they gave them a daily drink that either contained a mixture of artificial colors plus a preservative or an identical looking placebo.
[08:18 –> 09:32] Dr. Ravi Kumar: Nobody knew which was which. And on the days the kids got the drink with the artificial junk in it, their hyperactivity behavior measurably went up. And then the most thorough review yet, from the state of California’s Environmental Health Office in 2021, looked at seven approved dyes and concluded that the synthetic food dyes are associated with hyperactivity and other neurobehavioral problems in children. They noticed that kids vary a lot in their sensitivity, which I agree with, and also that the FDA’s safe intake levels were set decades ago off of old studies that were never designed to catch these types of behaviors in kids in the first place. So I would say the dominant conclusion here is that artificial food dyes are linked to increased hyperactivity in some children. But what the evidence doesn’t say is that food dyes cause ADHD. And ADHD is a complex condition that is most certainly caused by multifactorial reasons. So artificial colors and some food additives are likely contributors, but not the sole cause of ADHD. So that’s artificial food colors, and I’m putting a lot of attention on them solely. But what about preservatives and other food additives?
[09:33 –> 10:45] Dr. Ravi Kumar: Well, remember that landmark study that tested colors plus a preservative? That preservative was sodium benzoate. And even though the dyes got all the headlines, sodium benzoate may be contributing to the problem as well. There’s actually a study from 2014 that looked at college students and found that the ones drinking more sodium benzoate heavy beverages reported more ADHD symptoms. This study had some weaknesses. It was a survey looking at association, not causation, and the data was self reported by these college students. And it was overall a much weaker design than the Southampton trial that was a clinical trial showing causation. But it matches the clinical trial data, and there’s animal data pointing in the same direction. And sodium benzoate is likely not the only preservative that is causing problems. It’s worth mentioning that there are other preservatives that almost nobody talks about. These are the synthetic antioxidants like BHA, BHT, and TBHQ. These keep fats from going rancid in things like cereals, chips, and frozen meals. If you look on the back of your nonorganic cereal box, you’ll likely see BHT in there. Even on chewing gum, you’ll see it all over the place. BHA in particular is really scary.
[10:46 –> 11:54] Dr. Ravi Kumar: The US National Toxicology Program has classified BHA as reasonably anticipated to be a human carcinogen since 1991. That’s the federal government’s own science program. And California has listed it as a known carcinogen under Proposition 65 since 1990. The European Union is looking at it as a possible hormone disruptor. And despite all that, it has sat in the American food supply for decades under the label generally recognized as safe or GRAS. So we’re eating these food preservatives with data suggesting that some of them are carcinogens, and nothing has changed. In February 2026, the FDA finally announced its opening of a formal reassessment of BHA to decide whether it’s actually safe. And this is that chemical we just talked about where the National Toxicology Program called it a probable carcinogen since 1991. And now the FDA says the next in line is BHT. So right now, we’re watching the system slowly circle back to check the homework it should have done 35 years ago, and that’s a good thing.
[11:54 –> 12:47] Dr. Ravi Kumar: It’s just a little late. Now what about artificial flavors? Are they also harmful? Because most of these foods that have artificial colors and preservatives are artificially flavored as well. Well, the evidence on this one is thin, and we can’t make a conclusion just from the data. But we’ll come back to a common sense way of thinking about artificial additives in food in a bit. And I think you can fold artificial flavors into that general structure for thinking about all of this. Hey, guys. I created this podcast because there’s too much confusion out there. There’s too much noise, too many conflicting messages about our health. My goal was simple when I made this podcast. I wanna cut through all of that and give you information that you can actually use. If that resonates with you, here’s how you can help. Leave a rating and a review on Apple Podcasts. Share an episode that resonated with you with someone else that you care about, and that’s how this show grows.
[12:47 –> 13:49] Dr. Ravi Kumar: That’s how we reach more people who are searching for answers. Thanks for being a part of this, and I appreciate your help. Okay, so before we talk about what to do about all this, I do want to mention some more regulatory framework that is actually starting to change. In January 2025, the FDA revoked Red 3 in food. Red 3 caused thyroid tumors in rats, and a provision in The US law basically forces the FDA’s hand on any additives shown to cause cancer in animals. Second, in April 2025, federal officials announced a plan to phase out remaining petroleum dyes, that’s Red 40, the yellows, the blues, with a target of the end of 2026, the end of this year. But this is not a mandate. It’s largely voluntary, with the government leaning on industry and industry agreeing to reformulate. So because of this, some companies are moving early to natural colors like beet and turmeric, while others are not. And in Europe, we often hear that these same artificial food colors are banned, but that’s not entirely true.
[13:49 –> 14:56] Dr. Ravi Kumar: Since 2010, the EU has simply required a label on foods with relevant colors, telling parents this product may have adverse effects on activity and attention in children. It’s a label, not a ban, and it’s been there for 15 years. The US has never required it. And honestly, I think putting labels on food is highly effective. If you have a food that says, hey, this synthetic chemical may cause hyperactivity in your children, or you have a label on bread that says, hey, this has an herbicide in it called glyphosate that may cause non-Hodgkin’s lymphoma, you’re much less likely to buy that product. And consumer pressure through informed consent by proper package labeling puts pressure on industry to start giving us safe foods. So I think it’s highly effective to just label things properly and ethically in the first place. Now even though the federal government is slow to pass regulations on industry, the states can have outsized influence through state laws. You see, industry doesn’t want to have different formulations for different states. They wanna have one formulation that they can distribute to all 50 states in The US.
[14:56 –> 16:01] Dr. Ravi Kumar: So when one state passes a law banning food additive, the large food companies are likely to remove that ingredient from the products that they send all over the country. West Virginia is a great example of a state that’s doing this. They passed a sweeping law in 2025, pulling seven dyes plus the preservatives BHA and propylparaben out of food, starting with school meals. California already bars several of these dyes from public schools. Other states are lining up, so the states are doing what the federal government spent decades not doing. So there’s the regulatory framework and what’s being done at the federal and state level. But how should we think about this potential problem? What is the most reasonable and common sense approach to food additives based on what we know? Well, here’s my take. When you’re talking about a synthetic petroleum derived chemical, one that offers you or your child zero nutritional benefit and has never existed in any human’s or animal’s diet since the beginning of time, the question should not be, has the science proved it’s harmful yet?
[16:01 –> 16:43] Dr. Ravi Kumar: The actual question should be, has science proven it’s safe and to a very high standard? That’s not a radical or unreasonable approach. It’s a precautionary principle, and it’s been argued formally in the food additive literature for years. It’s the logic behind Europe’s labels and behind these new state laws, and it’s the standard we already apply to pharmaceuticals. A new drug has to prove it safe and effective before it reaches patients, but a food color additive could ride into the food supply on a decades old generally recognized safe stamp and stay there basically unexamined until somebody fights hard enough to get it reviewed.
[16:43 –> 17:37] Dr. Ravi Kumar: So for some compound with a real meaningful benefit, I am willing to tolerate some uncertainty, and I think most people are as well. Medicine is full of this kind of risk benefit ratio. But for a cosmetic dye in a child’s breakfast cereal with no upside to weigh against the unknowns, my bar is simple. Prove to me it’s essentially certain to be harmless, or it doesn’t go into my kid or into me. The convenience or profit of a food company is not a good enough reason to run a long term, uncontrolled experiment on a generation of children. That’s my stance. You’re allowed to disagree, and reasonable people do, but that’s where the evidence and the logic have taken me. So that’s my take. But let’s say you’ve looked at the evidence, you’ve listened to what I’ve had to say, you read the literature for yourself, And now you’re saying you wanna remove food colors and additives from yours and your family’s diet. How do you do it?
[17:38 –> 18:53] Dr. Ravi Kumar: Well, the first thing to consider is that natural whole foods that are unprocessed will only have good old compounds designed exclusively by mother nature. You will not get any petroleum based synthetic chemicals in any whole organic food. So if you eat a whole food diet, you’ve already basically solved the problem. But if that seems difficult, you need to audit your food supply. These additives hide in places that will surprise you. It’s not just neon candies. Some children’s medicines and vitamins, certain toothpastes, flavored yogurts, some breads, pickles, dressings, microwave popcorn, and pretty much anything that’s processed and shelf stable will likely be laced with artificial colors, flavors, and preservatives. And don’t be tricked by healthy packaging. Plenty of stuff marketed as wholesome is actually processed garbage. The front of the box will never tell you. You have to look at the ingredient list, so start reading it. That’s basically everything you need to know about artificial food colors and additives. Now you can make an informed decision about your own food and your family’s food, which is much better than eating something that may be harmful and not even knowing about it. Please reach out to me if you have any questions. And until next time, stay curious, stay skeptical, and stay healthy. Cheers.