Published 11th May 2022

Turmeric: Are there really any health benefits, and is it safe?

Turmeric is a root-like spice native to the Indian subcontinent and Southeast Asia. It has a distinctive flavor and adds a golden color to dishes. 

People have used turmeric in traditional medicine for thousands of years, and more recently, scientists have begun to look closely at its potential health benefits.

The active ingredient in turmeric is curcumin, which is hailed for its anti-inflammatory and antioxidant properties. Curcumin is also available as a supplement.

Of course, turmeric is just one of the many foods that can impact your overall health and well-being. 

At ZOE, we run the largest nutrition study in the world, and we look at how your body responds to a range of different foods and food combinations.

Our unique at-home test analyzes your blood sugar and blood fat responses to the foods you eat, as well as the makeup of your gut microbiome. These factors can all affect your risk of long-term health conditions, including heart disease.

You can take our free quiz to learn more about how ZOE can help you achieve your long-term health goals.

Below, we’ll assess some of the health claims associated with curcumin, including heart health, arthritis, memory and brain function, as well as mental health conditions like anxiety and depression.

We’ll also consider safety and possible side effects. 

But first, we’ll look at different ways to consume turmeric and curcumin, the quantity you get in food and supplements, and how these levels compare with what scientists use in their studies.

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Amounts of turmeric and ways to take it

The potential health benefits of turmeric come from its active ingredient, curcumin, which has anti-inflammatory and antioxidant qualities.

But turmeric only contains around 3% curcumin. Because of this, scientists who study its effects often use very large amounts of curcumin — about 1 gram each day, and sometimes as much as 12 g. That’s far more than you would usually get from adding turmeric to food.

Your body does not absorb curcumin easily, so only a fraction of what you consume reaches your bloodstream. However, there are ways to improve this. 

Black pepper contains a substance called piperine, which can help you absorb up to 20 times as much curcumin. That’s why many high-dosage turmeric supplements also contain black pepper.

Also, curcumin dissolves in fat rather than water, so cooking turmeric in oil or taking curcumin supplements with a meal containing fat could also help you to absorb more of it.

In fact, scientists have used special techniques to add fat molecules to curcumin to make it easier to absorb. 

This “lipidated” curcumin is often used in scientific studies, as are curcumin supplements that contain other substances for increasing absorption.

6 benefits of turmeric assessed

Scientists agree that curcumin in turmeric has strong anti-inflammatory and antioxidant properties. It’s possible these may contribute to benefits for heart health, arthritis, brain function, and even certain mental health conditions. 

However, it’s important to remember that a lot of this research is still in its early stages, and most of the studies that we mention in this article only involved small numbers of participants. 

Much more research is needed to understand whether turmeric’s health benefits are significant.

For instance, the National Center for Complementary and Integrative Health explain that “no clear conclusions have been reached about whether [turmeric, curcumin, or related compounds] have benefits for health conditions.”  

And government bodies like the United States Food and Drug Administration (FDA) are still rejecting claims about the benefits of some turmeric and curcumin supplements, which they class as unapproved new drugs.

1. Anti-inflammatory effects

One of the most common claims you'll hear about turmeric is that it has anti-inflammatory effects, and there’s plenty of evidence to support this. But what exactly is inflammation?

In many cases, inflammation can be a good thing. It's your body's way of protecting itself — like the swelling around an injury when you start to heal or cells from your immune system fighting off disease. 

But when inflammation goes on for longer periods, it can be bad for your body, contributing to a wide range of long-term health conditions, including heart disease, stroke, and type 2 diabetes.

Scientists looking at the effects of curcumin on the immune system concluded that in large doses — for example, 1 g per day for 8 weeks — it can help reduce signs of inflammation in people at high risk of these chronic health conditions.

2. Antioxidant effects

Curcumin is an antioxidant. Antioxidants help reduce levels of “free radicals” in your body. 

Free radicals are responsible for a process known as “oxidative stress,” which can damage your cells. This can lead to a range of effects, from signs of aging, like wrinkles, to a greater risk of serious diseases, including cancer.

One review of studies looked at four trials involving over 300 people who took either curcumin each day or a placebo. 

The researchers were interested in the effects of pure curcumin, so they didn’t include studies that added piperine to increase absorption. Participants took an average of 645 milligrams of curcumin over periods ranging from 42 to 84 days.  

The researchers concluded that curcumin significantly increased the body’s ability to tackle free radicals and reduced amounts of a chemical compound related to oxidative stress.

However, the authors also note that not all of the studies they reviewed found an antioxidant effect. They also explain that more research is needed. 

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3. Heart health

The anti-inflammatory and antioxidant properties of curcumin may help improve factors linked to heart health.

A study involving 100 people with metabolic syndrome concluded that doses of 1 g per day of curcumin and 10 mg of piperine reduced “bad” cholesterol levels and increased “good” cholesterol levels.

In another small study, scientists recruited healthy people aged 45–74. They took 2 g of curcumin each day for 12 weeks. The researchers noted improvement in the function of endothelial cells — specialized cells that line artery walls. These cells are linked to artery health, blood flow, and risk of heart failure.

Another study involved 121 patients who had undergone heart surgery. It found that those who took 4 g per day of curcumin for 3 days before their surgery and 5 days afterward were 56% less likely to have a heart attack during their time in the hospital than those who took a placebo.

Those who took curcumin also had reduced markers for inflammation and oxidative stress.

4. Arthritis

Osteoarthritis is a painful and debilitating joint condition that affects over 32 million people in the U.S. alone. Some scientists are looking at curcumin as a potential treatment.

Some small studies hint at the potential benefits of curcumin on joint health.

For instance, in one small study, participants with osteoarthritis took 200 mg of curcumin each day, along with a soy-based ingredient to improve absorption. 

After 3 months, their self-reported symptoms had improved by an average of 58%, and they could walk four times farther in a treadmill test.

Some scientists are investigating whether curcumin might have the potential to help with rheumatoid arthritis. This form of arthritis is less common than osteoarthritis but is more closely associated with inflammation.

In a small pilot study involving 45 people with rheumatoid arthritis, participants took 500 mg per day of a curcumin supplement with enhanced absorption. 

The researchers found that curcumin reduced soreness and swelling better than the anti-inflammatory drug diclofenac. Surprisingly, it was also more effective than curcumin and diclofenac together.

Because this was just a pilot study, it was “open-label.” That means that the researchers and participants knew which compounds they were taking, making the results less reliable.

The European Food Safety Authority reviewed several curcumin studies that included people with osteoarthritis or rheumatoid arthritis. Their report concludes that there is not enough evidence to claim that curcumin can boost joint health. They write: 

“[A] cause and effect relationship has not been established between the consumption of curcumin and maintenance of joint function.”

5. Memory and focus

Early evidence suggests curcumin might provide immediate and longer-term improvements in brain function as you age.

In one study, researchers found that healthy adults aged 60–85 significantly improved their performance on tasks involving attention and short-term memory just 1 hour after taking a 400 mg dose of a lipidated curcumin supplement.

Participants who took curcumin for 4 weeks also saw sustained improvements compared with those who took a placebo.

As for many health claims around curcumin, researchers need to carry out much more work. As it stands, there is not enough evidence to conclude that it benefits brain function.

6. Anxiety and depression

The study above looking at memory and attention also found that participants who took curcumin experienced improvements in mood. 

Other researchers have looked more specifically at whether curcumin might help with mental health conditions, such as anxiety.

In one study, 30 people with obesity took either 1 g of curcumin or a placebo each day for 30 days before swapping to the other group. They rated their anxiety and depression symptoms before and after. 

Final scores for anxiety were significantly reduced for participants who took curcumin but not the placebo. However, there was no notable change in depression scores. 

Other studies have identified potential benefits for people with depression. One found that a 6-week course of curcumin (1 g each day) was as effective at improving symptoms as the antidepressant fluoxetine, which is also known as Prozac.

At ZOE, we run the largest nutrition science study in the world, with over 20,000 participants so far. Our data show that everyone’s responses to foods are different.

These responses are important because they’re linked to your risk of health conditions like chronic inflammation and heart disease.

The ZOE at-home test analyzes your blood sugar and blood fat responses to foods, and provides information about your unique gut microbiome.

With the ZOE program, you get personalized nutrition advice to help you eat the best foods for your body and your long-term health goals.

You can take our free quiz to find out more.

Safety and potential side effects of turmeric

Both turmeric and its active ingredient, curcumin, are generally considered safe at the levels present in food. 

However, the World Health Organization’s acceptable daily intake (ADI) of curcumin — up to 3 mg per kilogram of body weight — works out at around 1.9 g for a person weighing 140 pounds (63.5 kg), which is a lot less than many high-strength curcumin supplements. 

With that said, people taking part in small scientific studies have consumed much larger single doses of curcumin — up to 12 g — and daily supplements of up to 3.6 g over several months, and researchers have concluded that curcumin, even at these levels, was not toxic. 

But it’s worth being aware that a small number of participants did report isolated instances of the following side effects:

  • diarrhea

  • headache

  • yellow poop 

  • rash

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Summary

Turmeric root has a long history as an ingredient in both cooking and traditional medicine, and there’s currently lots of interest in its potential health benefits.

Curcumin is the active ingredient in turmeric but only makes up a very small percentage of it. In its raw form, it’s also hard for your body to absorb.

Scientific studies tend to use large doses of curcumin that you won’t achieve through diet alone. Or they use supplements that blend curcumin extract with ingredients designed to boost the amount that reaches the bloodstream.

Curcumin is known for its anti-inflammatory and antioxidant properties. There’s some initial evidence that high doses may help with certain aspects of heart health, brain function, arthritis, and mental health. However, the evidence is preliminary, and much more research is needed.

Turmeric and curcumin are generally considered safe, but studies suggest that some people may experience occasional side effects, such as diarrhea or headache, after taking large amounts.

If you enjoy the flavor of turmeric in lattes or curries, it certainly won’t do you any harm, and there might be some benefits. However, scientists need to do more research to determine the best way to take curcumin to make the most of its anti-inflammatory and antioxidant properties.

At ZOE, we know that everyone responds differently to foods and that these responses can impact your overall health.

The ZOE at-home test tells you about your personal blood sugar and blood fat responses to what you eat. It also provides information about your unique gut microbiome, to help you discover the best foods for you.

Taking our free quiz could be your first step toward achieving your personal health goals.

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