Selenium deficiency triggers a harmful process in heart cells that damages the energy-producing mitochondria and causes cell death, according to a 2026 study published in The Journal of Nutritional Biochemistry. Gram Research analysis shows that without enough selenium, a protective protein called Sirt3 decreases, allowing another protein called YME1L1 to become damaged at a specific location called K237. This damage stops mitochondria from producing energy and releases genetic material that triggers cell death. The study, conducted in pigs and laboratory heart cells, identified the exact molecular mechanism linking selenium deficiency to heart damage, suggesting that adequate selenium intake may help protect heart health.
Selenium is a tiny mineral your body needs to stay healthy, especially your heart. When you don’t get enough selenium, your heart cells can become damaged by something called oxidative stress, which is like rust forming inside your cells. A new study using pig hearts found that selenium deficiency triggers a harmful process that damages the energy factories inside heart cells, called mitochondria. Gram Research analysis shows that a specific protein called Sirt3 normally protects these energy factories, but without enough selenium, this protection fails. The good news is that scientists found the exact spot where this damage happens, which could lead to new treatments to prevent heart disease.
Key Statistics
A 2026 study published in The Journal of Nutritional Biochemistry found that selenium deficiency in pigs reduced the protective protein Sirt3 in heart cells, leading to damage at the YME1L1-K237 location and triggering cell death through a process called PANoptosis.
Researchers discovered that genetically preventing damage at the YME1L1-K237 location significantly rescued heart cells from death in selenium-deficient conditions, identifying this site as a critical control point for selenium-related heart damage.
The study showed that selenium deficiency caused mitochondrial dysfunction characterized by impaired energy production and release of mitochondrial genetic material into heart cells, demonstrating how a single mineral deficiency triggers multiple levels of cellular damage.
The Quick Take
- What they studied: How not getting enough selenium damages heart cells and what happens inside the cell when this damage occurs
- Who participated: Pigs were fed a diet very low in selenium to create a model of selenium deficiency, and heart cells from these pigs were studied in the laboratory
- Key finding: When selenium is low, heart cells lose a protective protein called Sirt3, which causes damage to the energy-making parts of cells called mitochondria, leading to cell death
- What it means for you: Getting enough selenium in your diet may help protect your heart from damage. Foods like Brazil nuts, fish, and eggs contain selenium. However, this research was done in pigs and lab cells, so more human studies are needed before making major dietary changes. Talk to your doctor about whether you need more selenium.
The Research Details
Scientists created a model of selenium deficiency by feeding pigs a diet containing very little selenium (0.030 mg/kg). They then studied heart tissue from these selenium-deficient pigs and also grew heart cells in the laboratory. To understand exactly how selenium deficiency causes damage, researchers used advanced techniques to look inside cells at the molecular level. They used special microscopes to see the structure of mitochondria, the tiny energy factories inside cells. They also used genetic engineering to create mutant versions of a protein called YME1L1 to test whether changing this protein could prevent cell damage. This allowed them to identify the exact spot on the protein where damage occurs and whether fixing that spot could protect cells from dying.
This research approach is important because it combines multiple levels of investigation, from whole organs down to individual molecules. By studying both living tissue and isolated cells, and by using genetic tools to test specific protein changes, the researchers could identify the exact mechanism by which selenium deficiency harms the heart. This kind of detailed understanding is necessary before scientists can develop new treatments or confirm that dietary changes will help people.
This study was published in a peer-reviewed scientific journal, meaning other experts reviewed the work before publication. The researchers used multiple advanced techniques to confirm their findings, which strengthens the reliability of their results. However, this research was conducted in pigs and laboratory cells, not in humans, so the findings cannot be directly applied to people yet. The study provides important clues about how selenium deficiency might harm human hearts, but human studies would be needed to confirm these effects.
What the Results Show
When pigs were fed a selenium-deficient diet, their heart cells showed signs of oxidative stress, which means harmful molecules called free radicals were damaging the cells. The researchers found that a protective protein called Sirt3 decreased in these selenium-deficient heart cells. Without enough Sirt3, another protein called YME1L1 became damaged through a process called acetylation, specifically at a location called K237. This damage to YME1L1 caused the mitochondria, the energy factories inside cells, to stop working properly. The mitochondria could not produce enough energy (ATP) for the cell to survive, and genetic material from the mitochondria leaked out into the cell, triggering a cell death process called PANoptosis. When researchers used genetic engineering to create a version of YME1L1 that could not be damaged at the K237 location, the heart cells were protected from this harmful process.
The study also showed that selenium deficiency caused changes in mitochondrial structure and shape, meaning the energy factories became disorganized and dysfunctional. The researchers observed that multiple cell death pathways were activated simultaneously in selenium-deficient heart cells, not just one single pathway. This suggests that selenium deficiency triggers a complex cascade of damage rather than a simple, single problem.
Previous research has shown that selenium is important for heart health and that deficiency increases heart disease risk. This new study builds on that knowledge by revealing the specific molecular mechanism, or the step-by-step process, by which selenium deficiency causes heart cell damage. Earlier studies identified that Sirt3 is important for mitochondrial health, but this research shows for the first time how selenium deficiency disrupts the Sirt3 pathway specifically through YME1L1 acetylation. This fills an important gap in understanding how a simple mineral deficiency can trigger complex cellular damage.
This research was conducted in pigs and in laboratory-grown heart cells, not in living humans, so the findings may not directly apply to people. The study used an extremely low selenium diet (0.030 mg/kg) to create deficiency, which may be more severe than what occurs in some people with inadequate selenium intake. The researchers did not test whether increasing selenium intake could reverse the damage once it has occurred. Additionally, the study focused only on heart tissue and did not examine whether similar damage occurs in other organs. Finally, the exact amount of selenium that humans need to prevent this damage, and whether dietary sources of selenium can provide adequate protection, remains unclear.
The Bottom Line
Ensure adequate selenium intake through your diet by eating selenium-rich foods such as Brazil nuts (just 2 to 3 per day), fish, shellfish, eggs, and whole grains. The recommended daily amount of selenium for adults is 55 micrograms. If you have concerns about your selenium intake or have heart disease risk factors, discuss selenium supplementation with your doctor. Do not take selenium supplements without medical guidance, as too much selenium can be harmful. This recommendation is based on strong biological evidence from this research, though human clinical trials are still needed.
Anyone concerned about heart health should pay attention to this research, especially people with a family history of heart disease, those with existing heart conditions, or people who follow restrictive diets that might lack selenium. People who eat a varied diet including fish, nuts, and whole grains likely get enough selenium. Vegetarians and vegans should be more mindful of selenium intake since plant-based sources vary in selenium content depending on soil selenium levels. People taking certain medications or with specific health conditions should consult their doctor before making dietary changes.
This research suggests that selenium deficiency causes damage gradually over time as oxidative stress accumulates in heart cells. If you increase your selenium intake, it may take weeks to months for your body to rebuild protective proteins like Sirt3 and restore mitochondrial function. You would not expect to feel immediate effects from dietary changes, but long-term adequate selenium intake may help prevent heart disease development over years.
Frequently Asked Questions
What does selenium do for your heart?
Selenium helps produce a protective protein called Sirt3 that keeps mitochondria, your cells’ energy factories, working properly. Without enough selenium, this protection fails and heart cells become damaged by oxidative stress and eventually die.
How much selenium do I need daily?
Adults need 55 micrograms of selenium daily. You can get this from 2 to 3 Brazil nuts, fish, eggs, or whole grains. Most people eating a varied diet get enough selenium without supplementation.
Can selenium deficiency cause heart disease?
Research shows selenium deficiency increases heart disease risk by damaging heart cells through oxidative stress. This 2026 study identified the specific mechanism, though human studies are still needed to confirm how much deficiency increases disease risk in people.
Should I take selenium supplements?
Talk to your doctor before taking selenium supplements. Most people get enough from food, and too much selenium can be harmful. Your doctor can test your selenium levels and recommend supplementation only if needed.
What foods have the most selenium?
Brazil nuts contain the most selenium (about 95 micrograms in just 3 nuts), followed by fish and shellfish, eggs, and whole grains. The selenium content in plants depends on soil selenium levels where they’re grown.
Want to Apply This Research?
- Track daily selenium intake by logging selenium-rich foods consumed (Brazil nuts, fish, eggs, whole grains) and aim for 55 micrograms daily. Use the app to set reminders for selenium-rich meals and monitor whether you meet your daily target.
- Add one selenium-rich food to your daily routine: eat 2 to 3 Brazil nuts as a snack, include fish twice weekly, or switch to whole grain bread. Use the app to build this habit by setting daily reminders and tracking completion.
- Monitor your heart health markers over time by logging any heart-related symptoms, energy levels, and exercise capacity. Track your selenium intake weekly to ensure consistency. If using the app’s health integration features, monitor resting heart rate and other cardiac metrics to observe long-term trends as you maintain adequate selenium intake.
This article summarizes research conducted in pigs and laboratory cells and should not be interpreted as medical advice for humans. Selenium deficiency in humans may differ from the experimental model used in this study. Before making significant dietary changes or starting supplements, consult with your healthcare provider, especially if you have existing heart conditions, take medications, or have concerns about your nutritional status. This research provides important scientific insights but does not replace professional medical evaluation and personalized treatment recommendations.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.