Can spices improve your health?

Kanchan Koya grew up in a house filled with wonderful fragrances from the spices simmering on her grandmother’s stove. In India, it was a common belief that spices were more than just pleasant tastes.

Ancient wisdom said they had medicinal properties, and it was common for household medicine cabinets to store dried spices, not pills. Kanchan grew up to become a molecular biologist, studying in the U.S. at Harvard Medical School.

When her lab began to investigate turmeric’s healing properties, the ancient wisdom from her childhood met the scientific inquiry of her adult life — beginning a lifelong obsession with the health benefits of spice. 

In today’s episode, Kanchan and regular guest Tim Spector help us understand whether there is any scientific evidence to support the health benefits of spices, the easiest way to add spice to your diet, and which ones to choose.

Kanchan Koya is the founder of Spice Spice Baby and The Radical Vitality Podcast, with a Ph.D. in Biomedicine from Harvard University and training from the Institute of Integrative Nutrition.

Tim Spector is a co-founder at ZOE and one of the top 100 most cited scientists in the world.

If you want to uncover the right foods for your body, head to and get 10% off your personalized nutrition program.


[00:00:00] Jonathan Wolf: Welcome to ZOE science and nutrition, where world-leading scientists, explain how their research can improve your health.

Kanchan Koya grew up in a house filled with wonderful fragrances from the spices simmering on her grandmother's stove. In India, it was a common belief that spices were more than just pleasant tastes. Ancient wisdom said they had medicinal properties and it was common for household medicine cabinets to store dried spices and not pills. Kanchan grew up to become a molecular biologist studying in the US at Harvard medical school.

When her lab began to investigate turmeric's healing properties, the ancient wisdom from her childhood met the scientific inquiry of her adult life beginning a lifelong obsession with the health benefits of spice.

In today's show, she helps us understand whether there is any scientific evidence to support the health benefits of spices. The easiest way to add spice to our diet and which ones to choose. We're also joined by regular guest, Tim Spector, one of the world's top 100 most cited scientists, and my scientific co-founder at ZOE to help understand why spices might be improving our health.

Kanchan and Tim, thank you for joining me today. Why don't we start with our usual quickfire round of questions from our listeners and start with can Kanchan? Kanchan, are there spices that I can eat to improve my health? 

[00:01:37] Kanchan Koya: Yes.

[00:01:38] Jonathan Wolf: Should I be giving spices to my children? 

[00:01:42] Kanchan Koya: Yes. 

[00:01:43] Jonathan Wolf: Is there any evidence that spices can help with menopause?

[00:01:47] Kanchan Koya: I am not sure. 

[00:01:49] Jonathan Wolf: Brilliant. We'll come back to all of those a bit later. And Tim can spice reduce inflammation. 

[00:01:55] Tim Spector: Yes. 

[00:01:57] Jonathan Wolf: Do spices affect my gut microbiome?

[00:01:59] Tim Spector: Yes, definitely. 

[00:02:01] Jonathan Wolf: Can spices count towards my target of 30 plants a week? 

[00:02:06] Tim Spector: Yes, they absolutely can. 

[00:02:08] Jonathan Wolf: All right. That's a lot more yeses than normal, but I think everyone's like, wow, this stuff actually does something. And, let's go and sort of dig into that all in a bit more detail. And maybe we could just start right at the beginning Kanchan, what is a spice? 

[00:02:21] Kanchan Koya: Right. Fantastic question. So I'm actually going to summarize from a research paper because I knew that question was gonna come up, in the international journal of molecular sciences, which basically says that the leaf, root, bark, berry, bud, seed, and stigma of a plant or flower used for purposes of cooking are commonly referred to as herbs and spices.

So that's the formal, scientific definition of an herb or a spice. 

[00:02:49] Jonathan Wolf: Got it. And it sounds quite broad. So, I think spinach is a leaf, isn't it? But I don't think my wife would accept that I was adding spices if I added spinach to my meal. So I guess in day-to-day usage, is there anything, that would identify, you know, when you are cooking, what defines that as... 

[00:03:04] Tim Spector: Maybe separating a herb and a spice? 

[00:03:07] Kanchan Koya: Yeah, definitely. So when I think of spices versus herbs, I really do think of the root, the bark, the bud, the seed. And then when you start talking about the leaves, I think more of herbs, either fresh or dried. And so when you think of spices, the difference between them and other sort of plant foods that we eat on a regular basis is really that they're often quite concentrated and traditionally have been used to enhance the flavor of food. And of course, some ancient medical systems also enhance the health properties of food. So that's kind of how I would think about spices versus, you know, other foods that we eat.

[00:03:41] Jonathan Wolf: And somehow they always seem quite concentrated when I think about spices, right? They're in a small little jar, as opposed to the quantities of food I tend to eat for anything else to give me flavor. Is that universal across spices? 

[00:03:53] Kanchan Koya: Yes, they do tend to be concentrated and used in smaller amounts. And I think it's a really good point because for a lot of people, that brings up the question, well, if they're used in such small culinary amounts, how can they possibly really have benefits of meaning, versus, eating a giant plate of sort of leafy greens or a huge plate of steam broccoli, you do have to wonder would a sprinkling of this or that spice really make a difference? And I guess that's what we're gonna talk about today.

[00:04:20] Jonathan Wolf: I think that is exactly the question. And maybe I'd love to do it a little bit through your own story because we talked before this call about your own passion for spices and how it began. How have you ended up with your whole focus on spice?

[00:04:34] Kanchan Koya: Yeah. So I grew up in India for the first 18 years of my life. As several listeners might know, India is obsessed with spice, the spice box, or the Dabba, it's called in India, is really an integral part of every Indian household's kitchen. But it's also an integral part of every Indian family sort of pharmacy and by pharmacy, I mean the F-A-R-M, farmacy, natural medicinal foods that we eat, the ancient Indian medical system of Ayurveda has really revered spices and really put a lot of weight on their potential health benefits.

So I grew up with a lot of that ancient wisdom just sort of passed down by my family, my grandma, that sort of thing. And then, to be honest, didn't think much of it. In fact, I thought it was a bunch of maybe woo-woo. Not really valid. I was sort of a scientist, I wanted to do serious science. So I came to the US to study.

I found myself at Harvard medical school doing my Ph.D. in molecular cancer biology, and my lab at the Dana-Farber Cancer Institute actually started to study various polyphenols and plant-based compounds in a screen against breast cancer in vitro in cells. And one of the compounds on the screen was curcumin.

And I was collaborating on this project with a postdoc and he said: "oh, look! You know, turmeric is one of the compounds in the screen or curcumin, the bioactive from turmeric." And it was definitely a real aha moment for me because I think I had sort of discounted or not really paid attention to a lot of this wisdom that I grew up with.

And here I was at a research institution that was starting to look at some of these polyphenols found in spices and it just planted a seed for me that maybe there is something to these ancient components in food that is now being validated by modern science and then fast forward to sort of when I became a mother. And started to give my son spices in his baby food. And I had a lot of questions from my other mommy friends here in New York City as to whether that was even legal or allowed. And it just got the wheels turning in my mind about how maybe I could educate people about spices and really as a gateway into this world of food for health and food for micronutrient enhancement. And that led to the platform that is now a Spice Spice Baby. 

[00:06:55] Jonathan Wolf: That's amazing. And so what do we know about how spices affect our health? 

[00:07:00] Kanchan Koya: Right. That's the million-dollar question. So, you know, for a long time, we had a lot of evidence, mostly in vitro, sometimes dubious, not in the best journals, looking at the properties of these polyphenols or phytochemicals found in spices.

So these are individual compounds that have been studied in different spices, and they're often looked at, for their properties in a test tube on cells, and their antioxidant capacities, there was a growing body of evidence that spices contained these compounds. These compounds seemed to have benefits in vitro, and then there were small studies here and there.

Not the best sort of done, not the largest sample sizes, that were starting to show some benefits, like the ability to regulate blood sugar in the case of cinnamon or, you know, some other anti-inflammatory spices, like turmeric, their ability to block inflammation or at least reduce or regulate inflammation.

And for a long time, I just told people. We have so much growing evidence in vitro that these things can be helpful. There's really no downside to using them. We're waiting for more human kind of control, randomized control data. So in the meanwhile, let's just enjoy them because they make our food really delicious.

And there's really no downside. And there might be a health benefit, but I will say in the last few years, we have started to see some better studies in humans that have given me a lot more sort of optimism about the true benefit of these components in culinary amounts. So very often the studies in the past looked at very concentrated doses of spices and things that would be hard to achieve in culinary amounts. And now we have studies saying, you know, what, a teaspoon of a spice blend in sort of a junky high fat high refined carbohydrate meal may actually be able to regulate inflammation after that meal. And we can get into some of these studies, but I think now we're really starting to see more evidence that in addition to the in vitro characteristics of these polyphenols, there might actually be real benefits in culinary amounts.

[00:09:06] Jonathan Wolf: And Tim, you are normally the first to be skeptical about a pervading view of food. So on spices?

[00:09:14] Tim Spector: When you look at the studies in general, you do see lots of papers. You're getting multiple papers from countries like Iran or Pakistan or places that aren't really high up in the Western view of science that is looking after their own spices and perhaps paid by the government to write these papers that are down 20 or 30 people that wouldn't normally meet the quality you'd find in the top journals. So it is hard to assess these, they're often paid by the manufacturers just like happens in other areas of food, like, you know, giant nut conglomerates, et cetera, doing the same thing.

So I think we do have to be skeptical about the actual literature. But as Kanshan says, you know, we've got good theoretical reasons to believe it. And what we do lack is really rigorous studies in large numbers of people. So we do need though, a leap of faith to go from the fact that these spices and herbs are, are actually packed with the things that we know are good for our bodies.

From other experiments and take the few good studies that we have got and, and extrapolate them. So we should maybe look at some of these claims, some of the more extreme claims that you know, for example, you know, I took this turmeric powder and was completely cured of cancer with a very large pinch of spices.

But at the same time, realize that you know, these things might have a place in helping all these things along. And that that's the middle ground between the extreme claims and they don't work at all is, is where I think most food experts are seeing this. And luckily the last few years, we have seen more rigorous studies in a few of these areas.

And I think the fact that we can now start to measure things like the gut microbiome effects gives us a way of looking, in short term at practical ways of doing these studies, rather than waiting for people to do impossible studies, to do, you know, waiting to get cancer or heart disease or whatever, and taking spices or not, which would take an impossible length of time. So we are moving in that direction. And there are a few examples that I'm sure Kanchan and I can come to discuss that we'll highlight. 

[00:11:27] Kanchan Koya: And I'll just add one thing, along the lines of what Tim was saying, you know, I think many people look to spices or other sort of superfoods, as these magic bullet solutions for health problems.

And I think if you step back and look at the data from a sort of a larger lens, it really is about certain dietary patterns. And I think this emerges for any healthy food. So it's not about, you know, overloading on turmeric for inflammation control. It's about following a dietary pattern that we know in an evidence-based way is gonna support healthy inflammation and then incorporating a polyphenol-rich spice like turmeric.

I really see that as the approach versus the sort of like, what should I take every day in copious amounts to solve my problem. And I think there's when the dubious claims really start to come in. 

[00:12:16] Jonathan Wolf: So Kanchan, will you tell us a bit about the latest science, because it sounds like there have been some really interesting papers just in the last few years that have really lifted above what's been there in the past and I think it would be, without scaring us away, with too much of the science, what has that actually been telling us? 

[00:12:30] Kanchan Koya: Yeah. So for a long time, we had a lot of evidence, as I was saying that spices contain these anti-inflammatory compounds that seem to affect different players and inflammation. So inflammation is a really complex kind of molecular symphony cascade and the body with lots of different players.

And the cool thing is. The different components in different spices, at least in vitro seem to be hitting different components in inflammation. So potentially having a synergistic effect, working together and a team at Penn state university just last year actually said, Hey, since most people don't eat a single spice in isolation. Especially in cultures that have traditionally used spices, they're often used as spice blends. And given we know that different spices have different compounds that might work in concert. Why don't we make a blend and test it in humans to see what it does to markers of inflammation? So this was a blend and this is, you know, to Tim's point about this kind of reductionist view versus a more holistic view, the blend contained, I'm gonna list the spices really quickly, just to give you a sense of how many spices were in the blend.

They were obviously trying to create a research study that was likely gonna give them some results. And so the blend had turmeric, ginger, cinnamon, coriander, cumin, red pepper, black pepper, thyme, oregano, parsley, basil, rosemary, bay leaf, ginger, and cinnamon.

[00:13:57] Jonathan Wolf: I'm getting hungry, just listening to you list the ingredients, which doesn't normally happen when people discuss clinical studies with me. So this is more fun than normal. 

[00:14:05] Kanchan Koya: Right. And so what they found is when they took this blend and they added it to sort of a junky, modern standard American diet meal. It happened to be a refined carbohydrate and saturated fat-laden hamburger. maybe it was McDonald's. I'm not sure. No, we don't wanna throw McDonald's under the bus, but whatever it was some kind of junky meal and they either exposed subjects to the meal alone.

The meal with about half a teaspoon of the spice blend and then with a teaspoon of the spice blend. And they found that a teaspoon of the spice blended in the meal, which again is very doable. Being someone who cooks with spices adding a teaspoon of a spice blend to a burger, for example, is very doable, and something you would do as a cook actually resulted in a reduction in several biomarkers of inflammation, right after the meal.

And so that to me was really exciting. Because it shows that spices and culinary amounts might have positive effects. It shows that again, the blends are really powerful and it makes sense if you think about the mechanism of action of the different components in the spices and how they work in synergy.

So for me, that was one of the more compelling sets of evidence to suggest that maybe spices have benefits in real-time in our bodies, in culinary formats. The second study, which I know Tim knows is the one that came out in a scientific report a couple of years ago, or maybe even last year, looking at the effects of, again, a spice blend.

It was an Indian curry blend on changes in the gut microbiome. And they found essentially shifts in the microbiome, even after a single meal. With the spice blend. And it seemed to be that people who didn't routinely have spices had a more pronounced sort of effect or positive change in the gut microbiota.

[00:15:53] Tim Spector: So I think they're really two key studies that we really didn't have available to us until this year. And so it's moving the whole area onto a new level, which I think is really exciting that people are taking this seriously. They're getting the big grants to do it. And getting these papers written and out there.

And I think the link of the microbiome is really crucial because if you treat the microbiome like a new organ, it shows how these spices can actually affect our bodies. That has lots of long term health consequence rather than just short term. Cause a lot of the inflammation markers are just short term, but if you combine both of them, then you can really see that big effect.

And in the ZOE PREDICT studies, when we looked at foods, microbes, and health outcomes in the natural medicine paper, it was buried in that paper, which was so massive. It was hard to find it. We did see that, if you took chilis, it did reduce inflammatory bugs. It was associated with reduced inflammatory bugs.

People who regularly had chilis had fewer proteobacteria, the inflammatory ones, and they increased Akkermansia, which some people might have heard about because we talk about it a lot. It's a bug that's associated with good health and generally good metabolism and, and weight loss. And that's both in mice and in our studies.

[00:17:07] Jonathan Wolf: So I think everyone listening to this is, right, okay. I'm sold. I need more spice in my diet. So they're like, okay but, which, right? There are thousands of spices that you could find. Well, let's say we're just stepping into this. What spices should we look to add? Where is it that there's real evidence?

What should be our initial sort of shortlisting Kanchan? 

[00:17:26] Kanchan Koya: Yeah, I get this question all the time and it's kind of hard to choose based on that list that I sort of reading off, you know, with all the spices in the blend, the researchers commented that they don't yet understand which spices in the blend are more or less responsible for the positive effects on inflammation.

So sort of hard to choose, but I have come up with a list of five spices. That I think every sort of spice beginner could begin to embrace in their kitchen and then build from there.

[00:17:54] Jonathan Wolf: I'm taking notes right now. 

[00:17:57] Kanchan Koya: All right. So number one would be turmeric. There is such a large body of evidence around the health benefits of curcumin which is the main studied bioactive in turmeric. There are other bio-actives in turmeric. So for people who just wanna go straight to the curcumin supplement, I still recommend using the whole spice and getting that whole sort of food matrix effect, because you're getting all of the polyphenols and things we haven't yet identified.

[00:18:25] Tim Spector: That's true for all spices really, isn't it? 

[00:18:27] Kanchan Koya: Yes. Absolutely. 

[00:18:28] Tim Spector: Go for the whole one because there might be a hundred others that are doing an even better job than we haven't studied. 

[00:18:35] Kanchan Koya: Yes. Use the whole spice instead of running to the supplement store to get the concentrated version, there's room for supplements to check with your physician in certain situations, it might be helpful, but when using it in culinary sort of settings for an overall healthy dietary pattern. The whole spice wins. When using turmeric it's really important to pair it with black pepper. So one of the limitations of turmeric benefits is the poor bioavailability of curcumin. It's cleared pretty rapidly by the liver and it appears that piperine which is another polyphenol found in black pepper can slow down that clearance and it turns out you don't need that much pepper.

So for people who are like, oh, but I make my golden milk and I don't really want black pepper in my turmeric latte, you literally need a very small amount. A pinch will sort of do the trick. turmeric and black pepper would be the first two, just because they go hand in hand and pepper have benefits too. In and of itself.

It has anti-inflammatory compounds. It has some, at least in vitro, cancer-fighting properties and that sort of thing. The third one would be cinnamon. So it's been pretty heavily studied for its ability to balance blood sugar. There are several small but, you know, interesting research studies, looking at the ability of cinnamon to reduce blood glucose levels and to regulate A1C, which is another marker of insulin sensitivity, even LDL cholesterols, particularly in people with diabetes, the results are mixed. We need larger, more. Sort of convincing data, but -

[00:20:08] Jonathan Wolf: And presumably not if it's wrapped in a cinnamon roll, I'm thinking like most of the things I associate cinnamon with, to be honest, I feel are probably not very good for blood sugar control. So we, I sort of, need to rethink the set of foods that I would associate this with. Right?

[00:20:21] Tim Spector: They spray no cinnamon in those. It's all artificial flavoring, I imagine.

[00:20:26] Jonathan Wolf: Tim you're always depressing me with these facts. 

[00:20:29] Kanchan Koya: But you bring up an interesting point because there is one cool study that looked at the addition of a teaspoon of cinnamon to rice pudding, which isn't maybe the healthiest food because it's, you know, laden with refined sugar and all that. And it did seem to reduce the blood sugar spike when the rice pudding was laced with a teaspoon of cinnamon. So, if you are going to indulge in the cinnamon roll, maybe it's worth actually putting real cinnamon on top. 

[00:20:53] Jonathan Wolf: But you have some recipes for me that don't push me towards, sort of these sorts of cakes and desserts with cinnamon?


[00:21:00] Kanchan Koya: I mean, I think cinnamon is unfortunately associated with desserts and like holiday treats and that's great, but it's also used in many traditional cuisines and savory dishes. You can put it in things like chili or lentil or regular bolognese. It goes into garam masala, which is an iconic Indian blend used in curry. So don't just save it for the desserts and sweet treats. 

[00:21:20] Jonathan Wolf: So it's much more versatile and it's actually in things, it's interesting, a bunch of things I didn't realize that you've just mentioned that I eat so I can do that without having to yank up the cinnamon roll. That's good to know, although I would've quite liked an excuse if I'm honest, but-

[00:21:34] Kanchan Koya: I'm sure many people would. It also seems like about half a teaspoon to a teaspoon a day is a kind of what is thought to be optimal for balanced blood sugar. It's important to note that there are two kinds of cinnamon. So the one that you find regularly at your regular grocery store is called cassia cinnamon, and then there's a special variety called true cinnamon or Ceylon cinnamon, which comes from the island country, Ceylon or Sri Lanka.

And the reason I bring this up is that if you are someone who's really embracing cinnamon in large amounts in your smoothies and oatmeal or whatever, it might be worth going out of your way to find the true cinnamon varietal because cassia cinnamon has coumarin, which at large enough doses might have some liver toxicity effects.

So I always tell people, if you are gonna go all out and kind of really incorporate cinnamon into your life, go out of your way, find true cinnamon. You can get it online. It has little to no levels of coumarin. So it shouldn't be an issue even if you consume sort of a teaspoon a day. So that's three! 

[00:22:37] Jonathan Wolf: Don't think the cinnamon balance out the smoothie, which is one of the meals that we see has the worst blood sugar control across, you know, now 30,000 people. So as always, I guess you have to be very thoughtful about- 

[00:22:48] Tim Spector: You're looking for other alternatives. Aren't you? Aren't you, Jonathan?

[00:22:52] Jonathan Wolf: So cinnamon is fantastic. What else is in your five? 

[00:22:57] Kanchan Koya: So in my, my fourth one is sumac and that's because I grew up around spices, but sumac was not one of them. And I wish it was, it's probably my favorite spice.

So I'm a little bit biased. It also comes from the middle east. It grows on this bush and it has this beautiful purple hue. And as we know the color purple in the plant kingdom signifies these anthocyanins, which are really wonderful, again, phytochemicals that have anti-inflammatory cardiovascular protective effects.

It's also incredibly versatile to use. If you've ever been to a Middle Eastern restaurant and found your hummus with this purple kind of powder or your baba ganoush, that's sumac. It's very easy to sprinkle on things, whether it's your salads, whether it's your scrambled eggs or your avocado toast. So for the versatility and the anthocyanins, it makes my top five list.

And then number five, I'm gonna throw in probably one of my all-time favorites, which is ginger. And I know this kind of blurs that line between, you know, a spice and herb, a root and aromatic, but ginger can be used as the fresh root. It can also be ground down into a dry ginger powder and there's a huge body of evidence growing around ginger's benefits, whether it's inflammation management or digestion, it seems to really help with sluggish digestion.

So it helps to move food along the GI tract. It also can help with nausea, especially in pregnancy, always check with your doctor, obviously, but it has been shown in small studies to relieve symptoms of nausea. It may even help with some sort of metabolic health and blood sugar balance. And it's just so easy to use, you know, grate ginger into your curry, grate it onto your salad, make a tea.

It's very versatile and very easy to use. So those would be my top five, but obviously, I could keep going because there's a whole bunch that people should also explore. Don't stop at the five, but that's a good starting point. 

[00:24:46] Jonathan Wolf: Talk to us a bit about doing this. So imagine there'll be listeners here who are super comfortable, they're using loads of spices and they're like, oh, that's great.

But there'll be people here for whom this all just feels foreign to them. And they don't really know how to approach this. They might be thinking, right, I really wanna do this, but how do I actually bring this into my dietary pattern? The way I'm cooking if I'm a complete beginner. 

[00:25:09] Kanchan Koya: Yes, the number one piece of advice I give people is don't try to change your diet, to accommodate spices, add spices to your existing foods.

That's the best place to start. So very often people get intimidated because they think, oh, if I have to use spices, now I suddenly have to start cooking all this food. I don't really know how to make it, I need to go buy cooking. Books around Thai food or Indian food or Mexican food or whatever, you can take your daily favorites, your sort of global daily favorites.

I'm just gonna throw three examples, oatmeal, and avocado toast. And maybe, I don't know, what's the third popular breakfast, like some sort of like eggs. You know, with cream-

[00:25:45] Tim Spector: Bagels and cream, cheese.

[00:25:46] Kanchan Koya: Bagels and cream cheese! 

[00:25:48] Jonathan Wolf: Yogurt and berries. 

[00:25:50] Kanchan Koya: Yeah. Yogurt and berries. Exactly. And you know, how can you add some of the spices I mentioned or some other spices to those things?

So, you know, oatmeal, add some cinnamon, you can add a little sprinkling of cardamon and a little ginger, and now you have something that's really flavorful and you're incorporating some of these polyphenols in a simple way. Avocado toast. I mean, there are loads of things I do to my avocado toast, but you could sprinkle it with a little cumin and coriander and chili and a little lime juice to give it a bit of like, sort of a Mexican nacho flare.

You could put some sesame seeds and black onion seeds, or a little fennel seed. I mean, avocado toast is the perfect canvas to play around with in your spice box. And then fruit and yogurt. Again, you know, you could shave a little nutmeg, you could do the cardamom, cinnamon, again. A little bit of ginger clove is really nice in the winter months because it's warming and actually of all the spices might have the highest polyphenolic content per sort of gram.

[00:26:46] Tim Spector: And it's an anesthetic as well. Isn't it? 

[00:26:49] Kanchan Koya: Right. People suck on it for toothaches. Exactly. 

[00:26:52] Tim Spector: And trials actually show that works, Jonathan. So it's not just an old myth. They've done proper trials. 

[00:26:58] Jonathan Wolf: That's amazing. So you need a lot of cloves to, protect yourself from the cold winter, I guess, but, it's better than nothing.

[00:27:06] Kanchan Koya: Right. So I think the theme is to take your daily favorite foods and start adding spices to those in simple ways. And then you can get adventurous if you like and start cooking, you know, foods from cuisines, maybe you're less familiar with that are more spice heavy. And the second thing I'll say, because I get this all the time is people say, I want to use spices, but I don't like hot food.

And I think this is the biggest sort of myth that all spices are spicy. You can have spice-forward foods that aren't hot at all. So it's the chili peppers. Maybe the black pepper for people who are really sensitive would confer that sort of heat element. That can be uncomfortable. But if you think of all the spices we've talked about, they're aromatic, flavorful, and fragrant.

They are spice-forward, but they're not hot. So don't assume that all spices are spicy and therefore you have to stay away from them.

[00:27:56] Jonathan Wolf: Quite a few of them also sounded like work. You know, you were talking about, I've gotta shave this thing on top of my yogurt and we all know that we're very busy in the morning and probably many people listening to this podcast have already been trying to figure out how to improve their breakfast, to get somewhere healthier.

Like if I wanna get the best health benefits here, and I'm trying to find the balance of effort, are there sort of hacks to make this easier for us? 

[00:28:18] Kanchan Koya: Right. So definitely sprinkling an already ground spice onto your avocado toast is a great starting point. And you're still getting those polyphenols.

So don't make it overly complicated if that's gonna be a hurdle, but you raise a really good point because we do have studies that show that how you cook with the spice can impact. The health benefits. So turmeric and curcumin seem to be really activated when you expose them to heat, which is why, if you watch traditional cultures cooking with turmeric, they often add the turmeric to a fat source, like ghee or oil, and they let the spice sort of bloom in the fat for 30 to 60 seconds.

That seems to enhance the bioavailability of the curcumin and wake it up. And then they will add their vegetables to that or their lentils or beans, or then drizzle that turmeric oil over something. So if that's sounding like a lot of work, you know, it, it might be.

[00:29:15] Jonathan Wolf: Well, at least it's now dinner, right? So I guess dinner is normally somewhere you might be willing to put more-

[00:29:19] Tim Spector: But as a general rule, I mean, there are exceptions. People often by mistake, add the spices at the end of the cooking rather than right at the beginning. And I think that's, for those very reasons, not only improves the taste, but also the health properties. And I think that those people should learn that. 

[00:29:35] Jonathan Wolf: That's amazing. So this is real, like the timing at which you would add, these ingredients really change the health impact.

[00:29:41] Tim Spector: Yeah. 

[00:29:41] Kanchan Koya: Yep. So there's evidence that exposing a lot of these polyphenols to fat, and heat is beneficial, which is again, how a lot of traditional cultures cook with these spices. They layer them into the dish during the cooking process. Sometimes people will finish the dish with the same spice. And if you talk to chefs, they'll say, oh, it's a nice way to kind of reinforce the flavor and get a slightly different nuanced aspect of flavor. But I think there's actually a cool, scientific reason to do that, which is, that it seems like some of these beneficial compounds are enhanced with heat and fat and some of the antioxidants may actually be reduced with heat. So when you're layering your dish cooking with the spice, but also finishing with say a dusting of chili pepper or cumin or chili flakes, you know, which is really common and easy to do. You're getting access to sort of everything the spice has to offer. Some of which are activated by heat. And some of it may be diminished by heat. And so, again, just going back to sort of the ancient wisdom, like we just, people intuitively did that through cooking maybe because they thought it tasted good, but they're actually might be health benefits to sort of cooking that way with the spices. 

[00:30:51] Jonathan Wolf: Final topic I'd love to cover before we wrap up, is this sort of about sort of quality of spices and how to store them?

Because we had lots of questions about this as well. And I think one of my big takeaways here is, you know, ideally, you would just sort of have this prepared and then you could find it so easy to add to your breakfast and your lunch or your dinner. On the other hand, it feels like, well, if it's pre-prepared am I losing all of these special qualities, and basically, do I need to have that very fresh turmeric or the fresh powder?

What does the science say? Kanchan, what's your view on this?

[00:31:22] Kanchan Koya: So we've talked so much about why spices are beneficial and how it comes down to these polyphenols, which I like to think of like compounds that are really alive. They interact with the elements with air, heat, and with light. So where you get your spice from and how you store it does matter.

I think for people who've never used spices. If all they can do after listening to this is go to their regular grocery store, pick up a few of the spices we've mentioned and start adding them to food. That's a great, sort of starting point. They're winning. I don't wanna overcomplicate it for people, but it is true that when you get your spice at a conventional grocery store, it's been about two years for the most part, between when that spice was harvested and making it to the shelf. 

[00:32:05] Jonathan Wolf: Two years? That's quite depressing.

[00:32:08] Kanchan Koya: Yes. But just like, you know, artisanal, olive oil, or coffee, there is a lot of innovation happening in the spice space. And there are small companies and entrepreneurs who are saying these spices are so incredible, even just from a culinary perspective, we wanna preserve their magic. So they're going directly to these single-origin farms sourcing the spice.

Not treating them heavily, not irradiating them heavily, and then bringing them much more quickly to market. You can search for single-origin spices. I feel like the spice trade is really going through a revolution, just like coffee did. And there are great spices out there you can get online. 

[00:32:47] Jonathan Wolf: If this has been two years before I can find it in my shop, in my grocery store, does that mean it doesn't work anymore? That nothing you're telling us is relevant? 

[00:32:56] Kanchan Koya: No, it does work because the spices they use in these studies are not single-origin ones. You know, they use just the ones you can find regularly. So it's not that they don't work. It's just that they probably have less potency.

I would say you can tell, even, as a chef, that when you smell the bottle, you can tell the difference. There's just less aroma coming out of a bottle from, you know, a, a two-year-old spice, one way around it is to buy the whole spice. And again, this may overcomplicate it for people, but if you are going to use cumin if you buy the whole cumin seed, dry-toast it, gently in a skillet and just blitz it in a coffee grinder that you've sort of dedicated to spices.

It was $20. That can be your spice grinder. You're gonna have much more preservation of those polyphenols in the whole spice than in the ground spice. So that's one way around, you know, not having to go to the artisanal spice source. I will say that some of these single-origin spices are more expensive, but you don't use that much spice.

You can get away with fewer amounts and, it's kind of like investing in a good bottle of olive oil because you really want those polyphenols, you know, we don't sort of think twice about that, but somehow we are like, we don't wanna spend, I don't know, 10 bucks on a really nice jar of turmeric. We'd rather get the 2,99 version I'm thinking of us dollars here.

But yeah. So I think it's like sometimes we just have to challenge some of these preconceived notions we have about what is worth spending on and what isn't and I'm biased, but I think it's worth getting a really nice high-quality turmeric to make magic in your kitchen. 

[00:34:29] Jonathan Wolf: I think whenever we speak to someone who's an expert in a particular area, then they of course always see the difference, right? Between what you get from the grocery store and high-end. But I think the positive message you're saying is because obviously lots of people, you know, particularly at the moment, right, are really conscious of the cost of living. That actually the stuff that I can get from the grocery store is really matching up to these studies you're describing.

And so actually I should feel I can access this as an entry point. And then if I become addicted to turmeric in the way you're describing that many of them, our listeners are to coffee, then they're gonna be sort of escalated up this pathway. 

[00:35:01] Kanchan Koya: Absolutely. Yeah. 

[00:35:03] Tim Spector: I wouldn't give the impression that they're expensive, Jonathan. I think most of these spices are one of the cheapest things that you pay for in a sort of weekly budget, cuz they do last a long time-

[00:35:13] Jonathan Wolf: Because we use so little and they last for so long.

[00:35:16] Tim Spector: They last a long time. So relative to the whole family budget, they're pretty trivial. And unless you're going for some exotic saffron that you want to get from a particular area of Spain and be aware because actually there is fraud at that top end, like in the vanilla market and the saffron market, you will get some fraud, but generally, most of these spices are pretty good value and cheap, I think at the moment. So spending just, you know, 50% more can get you a lot of advantages.

[00:35:44] Jonathan Wolf: Final question on this. What about storage? So I bought this. Many people have heard that you know, these expire after a certain amount of time, if I don't use it all up in a week, because I'm not yet quite as heavy on the spice as maybe I should be, what do I do? 

[00:35:56] Kanchan Koya: The best way to store them is away from heat and light in airtight containers because these compounds interact with the elements and will lose potency over time.

So keep them in a drawer or cupboard away from heat and light. Don't keep them right next to your stove. Maybe one cupboard or drawer was removed from your stove. But I like to tell people to put them in a place where they're easily accessible, so you will actually use them. And just one quick point is around sourcing, is heavy metal contamination.

So there was a recent report that looked at heavy metals in a bunch of spices and herbs and did find in some brands, worrying levels of heavy metals. We're gonna have some heavy metals in everything because unfortunately, that's the nature of our soil, but you can always write to the manufacturer and just make sure that they have tested and it's sort of below the sort of danger zone of heavy metal levels. 

[00:36:47] Jonathan Wolf: Amazing. Well, I have so many more questions that I would like to ask, but unfortunately, we have hit time. I would love to try and do a quick summary of what was a lot of different places. And I think also really fantastically actionable in terms of people listening to this.

And, and I am going to be going away and discussing with a family a whole bunch of changes to our diet. So I think first thing. You guys both really believe that spices can affect our health. And that's because it's full of these polyphenols. It feeds our microbes. And this seems to be the primary way in which this might be affecting us.

I think we got a magic list of five spices, Kanchan from you. And then I think a final thing about sort of storage is, you know, again, you can keep this for quite a long time. You wanna keep it away from heat and light, but basically, actually, I think you're painting a picture just to conclude that this is not that hard that maybe many of us and I think, me included, maybe a bit scared about a lot of this, we can go and do this easily and maybe we start with this magic blend and then we explore all the wonderful places and we will, we will also share some in the show notes, some links to some of the wonderful things that Kanchan cooks.

[00:37:51] Kanchan Koya: Yes. That's an amazing summary.

[00:37:53] Jonathan Wolf: It was wonderful to do this. I think there are all sorts of exciting future studies to look at some of these spices in more detail. Do you think we might have more to talk about in a year or two in this area? 

[00:38:03] Tim Spector: Yeah. I'd love to do some mass intervention studies where everyone takes a spice mix for a couple of weeks on their main meals and see what those effects are. I think it could be life-changing for many people. 

[00:38:15] Jonathan Wolf: Would you like to be involved in that, Kanchan?

[00:38:17] Kanchan Koya: Absolutely. Count me in. 

[00:38:20] Jonathan Wolf: All right. You heard it here first and we will figure out if we can make that happen. Because I think one of the things we know is for many of these problems, there's just not enough people, right?

Who's been involved in these studies. There's just not enough scale to understand it. So I think that'd be incredibly exciting and maybe there'll be some listeners who are excited to participate. Kanchan, Tim, thank you so much. I really enjoyed that. And look forward to speaking again soon. 

[00:38:42] Kanchan Koya: Thank you so much for having me. It was an absolute pleasure. 

[00:38:47] Jonathan Wolf: Thank you Kanchan and Tim for joining me on ZOE science and nutrition today, we hope you enjoyed the episode. If you did, please be sure to subscribe, and leave us a review. We do really read all your reviews and try and learn from them. If this episode left you with any questions, please send them in on Instagram or on Facebook.

And we'll try to answer them in a future episode. At ZOE, we want to improve the health of millions by understanding the right food for each of us to improve our health and manage our weight. Each member starts with an at-home test, comparing them with participants in the world's largest nutrition science study.

If you're interested in learning more about ZOE, you can head to and get 10% off your personalized nutrition program. You'll also find their links to everything we've discussed today and the magic varieties of spices that will hopefully make all of us healthier as always.

I'm your host, Jonathan Wolf. ZOE Science and Nutrition is produced by Fascinate Productions with support from Sharon Feder and Alex Jones here at ZOE. See you next time.