Should you spend money on turmeric supplements? Award-winning science writer and nutritionist Duane Mellor joins Live Talks to discuss the science behind curcumin and turmeric as a nootropic to boost cognitive function and memory.
People concerned about brain fog, cognitive issues, memory problems and more often turn to supplements — a rapidly growing industry that rakes in billions of dollars per year. With its anti-inflammation properties, many have eyed turmeric supplements to boost brain health or even help prevent Alzheimer’s disease and other forms of dementia. But unfortunately, many neurology and nutrition agree that it’s not quite that simple.
Award-winning science writer and dietician Duane Mellor’s work at Aston Medical School in the UK is focused on helping people understand the science behind claims like these to make more informed decisions about their health. He tackled some of the critical questions about turmeric supplements in a popular recent explainer on the supposed benefits of turmeric for cognitive health and brain function and the science behind those claims, and in this LiveTalk, he breaks down the science in this talk and answers key questions about turmeric supplements.
Below, he discusses how some supplements, while pricy, might only be unhelpful: They could also contain dangerous ingredients. Read on for the transcript of the conversation, or watch the video.
Being Patient: What’s the history behind turmeric, and why it’s thought to have medicinal properties?
Duane Mellor: For over 4,000 years, it’s been used in ayurvedic medicine, which is a stream that’s linked to the practice of Hinduism in the South Indian subcontinent. It was used to treat all sorts of things like arthritis, and it still has claims and some data linked to pain relief. So, it’s been used for a long time.
It’s used as a food substance, which, you know, it’s easy to wrap around the meat to stop the meat going off. So, it has a preserving effect on food. There are even some scholars that would argue that this is the gold of the gold, frankincense, and myrrh, that was taken into nativity because of its healing properties. It’s got a long history with humanity for culinary purposes, but also being used in the traditional practice of medicine.
Being Patient: When we talk about the medicinal part of turmeric, it’s the curcuminoids. Is that correct?
Mellor: Yes, [the most important active ingredient in turmeric is] curcuminoids — a complicated, carbon-rich compound, which contains hundreds of different compounds. The most abundant compound is one called curcumin, which is different from the spice cumin. It is a pigment color in there, and the turmeric produces a very vivid yellow pigment which is thought to be the active ingredient. In the test tube, it’s shown to be very powerful as an antioxidant protecting against free radicals.
We can show that it happens in a test tube and that it can affect cells in a test tube. But it may be more complicated than that since we have our own defenses, which means it might be a different problem in humans. If we actually look at the idea of this compound and gets into our bodies, that’s where we struggle a little bit because it’s not brilliantly absorbed.
Being Patient: When it comes to turmeric being absorbed into the bloodstream, is it because the particles are bigger?
The simple term is bigger. When you’re using soap for washing up, you need something to get the things that are fat to mix with water. The curcuminoids probably dissolve better in fats than they do in water, but to be absorbed, they have to go through water, to then go into the fat. It’s what we call lipophilic, because it is fat-loving — rather than being water-fearing, or hydrophobic — so it makes it very hard to be absorbed.
There are some studies, which again on many different animals, which use an extract from pepper, piperine, which sounds more like the spice than in this case. In conjunction with animal models, it seems to enhance the absorption of curcuminoids. I think the other thing to probably notice, although the science is not clear [as to its effects as a supplement], in the amounts used for cooking, there’s no problem with it—it’s perfectly safe. There’s no harm in doing it, and there are maybe small benefits. When we talk about the science, we can almost ignore the fact that people are using small amounts of this daily, and if it fits within their budget and it doesn’t cause a problem, it is safe. What we are possibly doubting is how powerful or how efficacious is it in solving the problem?
Being Patient: The amount in these supplements is based on animal studies, right? So, if we translate that to humans, it can require much more to see the benefits we’ve seen in animal studies, right?
It would depend from one study to another, but there’s one study where they gave it one gram per kilogram of body weight. So, we’re talking about a two-kilogram bag for that one effect. That was in a particular type of mouse model. Because again, that’s where it gets complicated because not all mice and experiments are the same. They’re bred for particular purposes. Then to behave in a certain way, their biology is altered. So, we can see these effects. There’s difficulty in translating, but that showed in reducing inflammation in the brain and reduced risk of cognition and aging of the brain in this mouse model.
“Although the science is not clear, in the
amounts of cooking, there’s no
problem with turmeric. It’s perfectly safe”
Also, mice brains age differently from human brains. If you extrapolate it to human needs, [there’s a big difference]. If you’re eating lots of vegetables and dishes and using turmeric as one of the spices in that, it can be a small part of a bigger, healthier diet. [Turmeric might result in some] small gains. But I think we need to focus on [the impact of these overall healthy lifestyle changes] as opposed to trying to get a big hit from one supplement.
Being Patient: What if you take a little bit every day? Will that continued use have an impact and act against inflammation?
Mellor: I highlighted one study where there’s a moderate benefit [from taking turmeric supplements] on pain, compared to placebo. In some patients’ cases, the individuals found it to be as beneficial as a sort of non-steroidal anti-inflammatories. I say, like ibuprofen, there are similar effects seen. So, the effects are modest. They’re not always life-changing. This is not necessarily quite the same as a placebo effect. Because if you’re actively making a decision to improve your health, one of those things is to take a supplement.
If you’re taking a turmeric supplement from a reliable supplier, if it is what it says it is, it’s not going to be harmful in sensible doses. Because you’re making an active decision to improve your health, you’re actually moving yourself to a healthier position.
You might have a modest effect and have some potential placebo effect, but also you’re changing your behavior slightly by going in that direction.
So, all those things are probably why a lot of people are already having a great benefit. Again, yes, you probably will because you’re moving on this from having a problem to finding a solution. The actual biology of that might be quite small as the actual benefit, what you’re doing and how you’re interacting with it, and you’re believing in it, which add up to give a greater effect of that supplement.
Being Patient: In your article, how many studies did you examine, and what were your key takeaways?
Mellor: For this article, I went through around about 10 or 12. There’s another article that is based on a review we did a number of years ago on the effect of turmeric on cognition. That was a more systematic scientific piece of work. This is very much aimed at giving an overview of the use and the challenges of turmeric. [In this article, we looked] at how it affects the thinking and cognition of the brain, and although there is promise in terms of brain function, there are challenges because not all the formulations are the same. You don’t know what you’re getting, you don’t know what percentage of that is the curcumin, you don’t know whether it’s been mixed in a mix, and if it’s trying to enhance its bioavailability in absorption.
“Although there is promise in terms of
brain function, there are challenges because
not all the formulations are the same.”
What we need is more research that actually looks at a standardized dose, with anything that helps it be standardized. That becomes interesting again because that then becomes proprietary so people can trade market. So, they’re more likely to invest in the research, and you’d see how bias is creeping there because you’ll see more noise from something that can be made more profit from. But, we do need more study of standardized sorts of formulations like this. We probably need to be more open-minded to welcome research that may not be published in English.
There’s a whole range of literature published in the various languages in India, which we don’t have access to. We need to be more open and engage in the literature in a sensible way. It’s very easy to be judgmental from a North American or European perspective that our science is better when we haven’t actually looked using the same rules at the different studies done elsewhere. So, we need to look more globally, realistically. But, then do the studies with sensible doses of known amounts, and then work with our regulators to actually certify what’s in the tablets, which I think will solve that problem. Then we’ll be more sure if we do have data that has been effective so that people can access those amounts.
Being Patient: I couldn’t think of a better test ground over a billion people who have turmeric regularly in their diet, you know, to understand the benefits. In terms of preliminary results of other promising studies, how were those studies conducted?
Mellor: It’s a test that you do, and they can be memory tests, they can be re-reversing information, and rapidly recording type tests. So if you’re looking at cognition, that can be quite a short-term thing over a fairly short period of time in it may be people at high risk of neurodegenerative diseases, bursts, it’s very hard to have studies where you go, let’s look at a population age 50, then follow them up, reach 70.
Those sorts of studies are 20 years long, very expensive, and very complicated. You mentioned about a billion people in the Indian subcontinent eating lots of turmeric. They also have lots of garlic, ginger, chilies, and alliums. You know, there are other things in their diet, lentils, physical activity, and also they have other health issues as well. So, it’s very hard to pick one thing. And I think that probably brings it back nicely that, yes, there’s some interesting stuff there. But it’s not the only thing we should do to try and look after our health.
“Yes, there’s some interesting stuff [in those studies]. But it’s not
the only thing we should do to try and look after our health.”
Our mind as well as our physical health, could be part of something. If you put in turmeric, as you mentioned, in a curry with lots of vegetables, lots of pulses, lots of other great healthy food, then there’d be a little effect of all these bits, rather than trying to rely on having a bigger dose as a supplement of just one thing.
Being Patient: How would the benefits of potential curcuminoids get into our brains? Or how does any supplement get into our brains, where we could see a benefit?
Mellor: What we’ve traditionally thought is a very simple model, that it goes into a digestive tract and gets absorbed somehow in body knowledge. That’s a bit of a challenge with curcumin. Then it goes to our circulation that gets to the brain, that it’s got another barrier to cross to get across into our brain, the blood-brain barrier. So, it’s got to go through a fat barrier, which is the cells that are lining fat, very small fat membrane, go through that into the water back out, again, be transported somehow in our blood, and then be transported across our brain. So that’s quite a hard journey.
There is another emerging area of science where they go, “Well, we see this going into the body, we see an effect, but we’re not really good at measuring a lot of exact compounds in the blood. Is something else happening?” That’s where the idea of the gut microbiome has come in. In a lot of the things that we can absorb, then interact with the bacteria with ourselves around them, then our colons, and they ferment and change these compounds. That may affect the balance of different bacteria, and if you change the bounds of these bacteria, they then act on the fibers and produce different what we call volatile or short-chain fatty acids. [These acids] then interact with our biology not just in terms of the immune function in our gut, but in terms of how we handle fats, things like cholesterol, also sugar and glucose.
“Our studies only tend to go one
little bit at a time, getting one
little tiny piece of a jigsaw.”
So, it can actually have massive effects on our health overall. A little bit might be absorbed, and a little bit might be working on the bacteria, and that has a positive effect on our health overall. How to demonstrate that is very hard to create. Our studies only tend to go one little bit at a time, getting one little tiny piece of a jigsaw. It’s not even the whole jigsaw piece. Probably the little bit connecting to another piece that we see each time we do a bit of research.
Being Patient: With your background as a nutritionist, is there anything for the brain that has been proven to be effective in terms of brain health?
Mellor: If you look at child development, pre-conception through pregnancy, there’s a lot of data being done over the last 50 years about omega-3 fatty acids and bringing some [more brain development] with children. There’s lots of discussion about the Mediterranean type diet. A diet rich in vegetables, low in added fats, low in added salt and sugar added, and lots of fiber. You know, the nuts, the seeds, or lentils, some fruit— that dietary pattern. Small amounts of alcohol, lots of alcohol, we know is bad for the brain. Modest amounts of caffeine may be good, so a little bit of tea and coffee may be a good thing.
I think I’d go one step further than just nutrition and what’s the composition of food. The thing we forget too often, and if we look at the successful societies in the world, where they live long, healthy lives, where they’re still active physically and mentally, is eating with other people, and sharing food. This is a big concern in the UK and in life as well. When we had the pandemic, people stopped eating together, they stopped socializing and socializing around food is something that we risk losing. We need to maintain that sharing healthy food with other people is part of what we are as social creatures. We need to remember it’s not just biology, there is a social aspect of our food behaviors, which contribute to our overall health, our brain health, our mental health, and our physical health.
If you look at every culture, every faith, and every culture across our globe, separately, has shared meals at the heart of its festivals and celebrations, and it brings people together. We need to have that on a daily basis, sharing food and enjoying healthy food together. Socialization is often a forgotten thing that keeps us healthy and connected.
This interview with nutritionist Duane Mellor about the science behind turmeric supplements has been edited for clarity.
Katy Koop is a writer and theater artist based in Raleigh, NC.