Will chili peppers extend your life?

Chili peppers are part of the nightshade family. Enjoyed around the world, they bring a spicy punch to any meal.

OK, let’s cut to the chase: Chili peppers won’t add years to your life.

But before you click that “X” on your browser, it’s worth sticking around because the research is pretty intriguing. 

And maybe, just maybe, chilis might extend your life … a bit.

Chilis and mortality

At ZOE, we know that a diverse diet packed with plant foods is the healthiest option. So, focusing on just one type of food is never the answer.

That said, there seems to be something a bit special about chilis: Scientists have found links between chili consumption and reduced mortality risk.

Let’s look at the evidence.

Chilis in China

Let’s start with a Chinese study from 2015. The scientists used data from almost 500,000 people in the China Kadoorie Biobank study. 

Participants were aged 30–79 at the start, and scientists followed them for an average of around 7 years.

They found that eating spicy foods more often was associated with a lower risk of dying during the follow-up period.

Specifically, they also found that eating spicy food more often was linked to a reduced risk of dying from cancer, ischemic heart disease, and respiratory diseases. 

Even when the scientists adjusted their analysis for a range of variables — including smoking status, education level, alcohol consumption, body mass index (BMI), and marital status — the associations remained intact. 

Impressive, right?

However, there’s a great deal of difference between lifestyles and dietary patterns in China and those in Western countries. Would scientists find the same relationship in the West?

U.S. chili chewers

In 2017, researchers carried out a similar study in the United States. This time, the data came from the National Health and Nutrition Examination Survey III.

The team followed more than 16,000 participants for an average of almost 19 years.

The term “instantaneous hazard of death” means the chance that a participant will die at any point during the study’s follow-up period.

OK, but what about people in Europe?

Italian spice

In 2019, scientists in Italy decided to take a look at this intriguing relationship. 

This time, there were almost 23,000 participants, and the researchers followed them for an average of around 8 years.

The authors write: "Regular consumption of chili pepper is associated with a lower risk of total and [cardiovascular disease] death independent of [cardiovascular disease] risk factors or adherence to a Mediterranean diet.”

How can we explain these findings?

The large studies above seem pretty convincing. But there might be other factors at work, influencing why eating chilis is apparently linked with reduced mortality risk. We’ll outline a few theories here. 

Do chili-eaters have healthier lifestyles?

One explanation is that people who eat chilis might have diets that are more healthy overall, compared with diets that don't include as many chilis. 

However, the Italian study found that “The health benefits associated with chili pepper intake are independent of the overall quality of the diet.”

For instance, people who didn't eat chilis ate fresh vegetables on an average of 6.8 days a week. Chili-eaters had fresh vegetables on an average of 7 days a week — so, not much distinction.

The U.S. study had similar findings: The chili-eaters ate slightly more fruits, vegetables, and meat than the non-chili-eaters.

Diet aside, in the Chinese and U.S. studies, regular chili-eaters were more likely to consume alcohol and smoke tobacco than those who ate fewer chilis. So, a healthy lifestyle doesn’t seem to be the answer.

Chilis and weight

Another theory is that people who eat more chilis are less likely to have overweight or obesity. This is because there’s some evidence that chilis might encourage weight loss.

Indeed, in the U.S. study, rates of obesity were slightly lower among people who did eat chilis (23.9%) than those who didn’t (25.4%). 

Similarly, in the Chinese study, individuals who ate the most chilis had a slightly higher average BMI. So, weight doesn’t seem like the defining factor here.

Other explanations

The authors of the Chinese study offer some other theories. For example, they suggest that individuals who regularly eat chilis might also include other spices in their diets. 

So, perhaps it’s not the chilis producing the benefits but a higher intake of spices overall.

Although the scientists excluded people with cancer, heart disease, and a history of stroke, we can’t rule out the role of other health conditions.

Finally, as with any observational study, there’s always a chance that some other factor the team didn’t (or couldn’t) control is driving the results.

So, we can’t directly relate the consumption of spices with decreased mortality.

 How might chilis protect you?

If chilis really do reduce the risk of cardiovascular and overall mortality, how would that work? Scientists don’t know, but they have some theories.

Some researchers believe that capsaicin — the compound that makes chilis hot — might hold the answer.

Capsaicin acts on a receptor called transient receptor potential vanilloid type 1 (TRPV1). 

One its jobs is detecting heat. So, when capsaicin binds to TRPV1, it provides that sensation of heat that comes from a fiery chili.

There’s also some evidence that this receptor might play a role in metabolism. For instance, animal studies have shown that activating TRPV1 might help counteract diet-induced obesity. 

At this stage, scientists are still getting to grips with TRPV1. It has fingers in many metabolic pies. 

For instance, there’s evidence — mostly from animal studies — that it might influence appetite, blood glucose levels, insulin sensitivity, and inflammation 

There’s also evidence from rodent studies that TRPV1 helps regulate blood flow to the heart.

To sum up: If chilis do reduce mortality risk, we’re not sure how. But the current theories are fascinating.

So, what should you do?

If you like spicy food, the evidence and theories above might be good news. But if you don’t, there’s no need to worry.

It’s also worth pointing out that for some people, including people with irritable bowel syndrome, spicy chilis can cause gut symptoms. 

So, if they don’t agree with you, pick another fruit or vegetable — they’re all good.