Selenium is a vital mineral that plays a crucial role in maintaining overall health and well-being. Found in a variety of foods, from nuts to fish, it supports important bodily functions, including immune system performance and antioxidant defense.

Research has shown that the amount of selenium in your diet can impact your overall health in many ways. For instance, one study found that getting enough selenium could help lower the chances of developing kidney stones in older adults. Selenium has also been linked to a reduced risk of arthritis and rheumatoid arthritis, along with supporting stronger bones. There’s even evidence suggesting that selenium might support better brain function.

Since cardiovascular disease (CVD) is the No. 1 cause of death worldwide, finding ways to support heart health is key. That’s why researchers recently tried to determine if there is a link between selenium intake and the risk of CVD, and their results were published in Scientific Reports. Here’s what they found.

How Was This Study Conducted?

To assess the link between selenium intake and cardiovascular disease risk, researchers analyzed data from the National Health and Nutrition Examination Survey (NHANES), a large study conducted in the United States to understand the health and nutrition of the U.S. population. This data provided insights into selenium intake from diet as well as various heart and blood vessel-related conditions, such as cardiovascular disease, heart failure, coronary heart disease, hardening of arteries, heart attack, chest pain (or angina) and stroke. The analysis included more than 39,000 participants.

To better understand how much selenium people were getting from their diets, participants in the NHANES study took part in two food recall interviews. Researchers used specialized tools to analyze this information and calculate how much selenium each person consumed from natural food sources, like fruits, vegetables and meats. Selenium from supplements or medications wasn’t included in these calculations, which allowed researchers to focus solely on selenium consumed through regular diets.

To identify heart-related health conditions, participants were asked questions during interviews, either directly or through a caregiver. These questions included whether a doctor had told them they had issues like heart failure, angina (chest pain), heart attack or stroke. If a participant answered “yes” to any of these questions, they were considered to have a history of cardiovascular disease (CVD). 

The study looked at several heart-related outcomes, such as coronary heart disease (CHD) and stroke, as well as other related issues like congestive heart failure. The researchers also collected a wide range of other details about participants, including their age, gender, race, education level, income and their history of drinking alcohol. 

On average, the participants were about 47 years old, with a fairly even split of women and men. The participants were grouped into three categories based on how much selenium they consumed in their diets, and relevant data was analyzed.

What Did The Study Find?

The researchers observed that participants who consumed moderate or high amounts of selenium experienced heart health benefits. The researchers also discovered specific tipping points for how dietary selenium intake relates to heart and stroke health. They found that consuming about 135.28 micrograms (µg) of selenium per day marked a key point where its protective effect against cardiovascular diseases and atherosclerotic cardiovascular diseases began to shift. Similarly, for stroke prevention, the key point was around 100.3 µg per day. Beyond those levels, the benefits of selenium diminished, highlighting the importance of balanced intake.

The participants’ average selenium intake was 114.67 µg per day, which is more than the recommended daily allowance for most adults. Among all participants, 8.57% had cardiovascular disease, but that percentage went down as selenium intake increased. People in the highest selenium intake group had a lower chance of conditions like stroke, heart failure and heart attacks compared to those in the lowest intake group. Even after considering factors like age, sex and race, higher selenium intake was still associated with reduced cardiovascular disease risk. 

When comparing the group with the lowest selenium intake to those with higher selenium intake, the data shows that people who consumed moderate amounts of selenium had a 16% lower risk of CVD in a fully adjusted model. This means that when factors like age, sex and race were taken into account, the moderate selenium group still showed a significantly lower risk. But for people in the group with the highest selenium intake, the protective effects were no longer significant. This suggests that while moderate selenium intake may help reduce cardiovascular disease risk, consuming the highest levels doesn’t necessarily offer additional benefits.

Additional data shows how selenium intake can impact various heart-related conditions. Moderate selenium intake, for example, resulted in a lower risk of

• coronary heart disease, by 20%
• congestive heart failure, by 30%
• heart attacks, by 25%
• angina, by 30%

Overall, these findings highlight the potential of selenium as a key nutrient in heart health. 

But this study has some important limitations. Because it only captures data at one point in time, the researchers couldn’t see how people’s eating habits change over the years. Diets can change as people age, and these changes could impact the link between selenium intake and heart disease risk, but this study couldn’t explore that.

Another limitation is that the researchers relied on participants to report whether they had heart disease, which means there’s a chance some people might not remember or share their medical history accurately. Lastly, because of the way the study was designed, we can’t say for sure if eating more or less selenium causes changes in the risk for heart disease; we can only see an association.

How Does This Apply To Real Life?

Based on these findings, incorporating selenium-rich foods into your diet could be a simple yet impactful way to support heart health. By including selenium foods in moderation, you may improve your overall selenium intake, which, as the study suggests, may be linked to a reduction in the risk of conditions like stroke, heart attack or other cardiovascular issues. However, balancing selenium consumption is key. Overconsumption might lead to diminishing benefits or potential health risks, so staying within recommended dietary guidelines is crucial.

The recommended daily intake of selenium varies depending on age, sex, and specific health conditions. For most adults, the recommended dietary allowance (RDA) is 55 µg per day. The tolerable upper intake level (UL) of selenium for adults is 400 µg per day.

There are plenty of delicious foods that are naturally rich in selenium, so adding them to your meals is simple. Here’s a list of great options to consider:

• Brazil nuts (they’re packed with selenium!) 
• Seafood like tuna, sardines and shrimp 
• Organ meats, such as liver 
• Eggs 
• Whole grains, like brown rice and whole wheat bread 
• Sunflower seeds 
• Mushrooms 
• Spinach 
• Poultry, like chicken and turkey 
• Dairy products, like yogurt and milk 

The Bottom Line

A study published in Scientific Reports suggests that selenium intake may be linked to heart health benefits. This article underscores the importance of balanced selenium intake, with research highlighting its potential to reduce the risks of various cardiovascular conditions—as long as you don’t overdo it. 

By incorporating selenium-rich foods into your diet, you can take proactive steps toward enhancing your well-being. But it’s essential to remember that moderation is key. Too much selenium may lead to adverse effects, so following dietary guidelines is crucial to maintaining a healthy balance.

It’s important to remember that while selenium alone isn’t a magic solution, it’s a vital piece of the puzzle in fostering a heart-healthy lifestyle. When combined with other positive lifestyle choices, such as regular physical activity and avoiding harmful habits like smoking, selenium may offer some benefits. Always consult with healthcare professionals to tailor your nutrition and wellness approach to suit your individual needs.