Consuming this nutrient alone can reduce the risk of a heart attack drastically

Cardiovascular disease continues to be the leading cause of death globally. Amid ongoing search for answers, a trace mineral often tucked away in nutritional discussions—selenium—has emerged with promising links to heart health.


But this isn’t just another trendy nutrient getting the spotlight. This time, the connection comes from a large-scale study using NHANES data (2003–2018), involving over 39,000 participants. The findings suggest that selenium, when consumed in the right amount through diet, may lower the risk of cardiovascular events like heart attacks. But like most things in nature, balance is everything.


What the buzz is about

What has stirred interest is a consistent inverse association between dietary selenium intake and cardiovascular disease. This means as selenium intake increased—within a particular range—the risk of heart disease appeared to decline.



The sweet spot? Between 55 to 145 micrograms per day.


However, this relationship isn’t a straight line. Beyond the threshold of roughly 135 µg/day, the heart-friendly benefits of selenium begin to taper off, and in some cases, might even backfire. That’s what makes selenium unique: helpful, but only when it doesn’t overstay its welcome.


The real star: Not supplements, but food

Many studies have looked at selenium levels in the blood, but fewer have asked the more practical question: how much selenium is entering the body through food? Since nearly 80% of dietary selenium is efficiently absorbed, it makes sense to focus on what’s on the plate.


Natural selenium-rich foods include Brazil nuts (in moderation), sunflower seeds, whole grains, eggs, and fish. The NHANES study clearly showed that dietary sources—rather than pills—are what really matter.



Why the heart cares

What makes selenium protective lies deep in the body’s defense system. It’s a critical player in antioxidant enzymes such as glutathione peroxidase (GPx) and thioredoxin reductase (TrxR). These selenoproteins guard cells from oxidative stress—a major villain in the heart disease story.


Low selenium levels have been linked with increased cholesterol and triglyceride levels, higher oxidative stress, and even poor cardiac enzyme function. But too much selenium might create reactive compounds that cause more harm than good. So the heart appreciates selenium’s help—but only in moderation.


But there’s a twist: Not everyone benefits equally

The heart-protective effect of selenium was found to vary depending on one’s hypertension status. For people without high blood pressure, selenium intake showed more pronounced benefits in reducing cardiovascular risk. For those with hypertension, the relationship was less clear.


This opens up an important conversation: heart health solutions are not one-size-fits-all. Lifestyle, existing conditions, and overall diet influence how selenium plays its role.



Despite the compelling results, the full story of selenium and heart disease remains incomplete. Some studies show no significant benefits from selenium supplements. Others reveal that too much selenium may trigger oxidative damage—especially if not paired with other nutrients or consumed through natural food.


The NHANES-based research had its strengths—a large sample and careful adjustments—but also limitations. Being cross-sectional, it can’t prove cause and effect. More long-term studies are needed to pin down selenium’s exact role in cardiovascular protection.