A supplement that boosts NAD+ (nicotinamide riboside) improved heart function and reduced stress in mice with mitochondrial disease, but it worsened blood cell production and anemia in the same animals. According to Gram Research analysis, this 2026 study demonstrates that NAD+-boosting treatments can have opposite effects in different tissues, helping the heart while harming bone marrow, suggesting these supplements need careful evaluation before widespread use in humans.
Scientists tested a popular supplement called nicotinamide riboside (NR) that boosts NAD+, a molecule that helps cells make energy. In mice with a disease that causes early aging of mitochondria (the cell’s power plants), the supplement fixed heart problems but caused unexpected trouble in bone marrow and blood cells. According to Gram Research analysis, this study shows that treatments helping one part of the body might accidentally harm another part, highlighting the need for more careful testing before using these supplements widely.
Key Statistics
A 2026 study in Cell Reports found that nicotinamide riboside supplementation enhanced heart contractility and normalized cardiac metabolic profiles in mice with mitochondrial progeria, while simultaneously impairing erythroid maturation and worsening anemia in bone marrow tissue.
Research shows that NAD+ precursor treatment caused accumulation of NADH/NADPH in proliferative bone marrow cells, disrupting heme biosynthesis and red blood cell development despite improving heart function in the same mice.
According to the 2026 Cell Reports analysis, chronic NAD+ boosting compromised erythrocyte maturation in mitochondrial disease models, demonstrating that tissue-specific metabolic consequences of NAD+ restoration remain poorly understood in humans.
The Quick Take
- What they studied: Whether giving mice a NAD+-boosting supplement could help them live longer and healthier when they have a disease that makes their cells age too quickly.
- Who participated: Genetically modified mice that develop early aging of their mitochondria (the parts of cells that make energy), compared to normal mice.
- Key finding: The supplement fixed heart problems and made the heart stronger, but it made blood cell production worse and worsened anemia in the same mice.
- What it means for you: NAD+-boosting supplements might help some organs but could harm others. Before taking these supplements, especially if you have a blood disorder or heart disease, talk to your doctor about potential side effects in different parts of your body.
The Research Details
Researchers gave nicotinamide riboside (NR), a supplement that increases NAD+ levels, to mice with a genetic condition that causes their mitochondria to break down prematurely. They then examined what happened in different tissues, the heart, bone marrow, and blood, to see if the supplement helped or hurt.
The scientists measured many different markers in each tissue type, including energy production, stress levels, and the ability of cells to mature properly. This approach allowed them to see the full picture of how the supplement affected the entire body, not just one organ.
By studying both the heart (which doesn’t divide and make new cells) and bone marrow (which constantly makes new blood cells), the researchers could understand how NAD+ boosting affects different types of tissues in different ways.
Most studies of new treatments focus on fixing the main problem in one organ. This research is important because it shows that boosting NAD+ in one part of the body can have unexpected negative effects in other parts. This finding could prevent doctors from recommending supplements that seem helpful but actually cause hidden harm.
This study was published in Cell Reports, a respected scientific journal. The research used a well-established mouse model of mitochondrial disease, making the findings relevant to human conditions. However, because this was animal research, results may not directly apply to humans. The study examined multiple tissue types, which strengthens the findings by showing the supplement’s effects across the whole body rather than in isolation.
What the Results Show
In the heart, nicotinamide riboside worked as hoped: it improved how well the heart contracted (pumped blood), reduced signs of cellular stress, and restored normal energy metabolism. The supplement essentially reversed some of the damage caused by the mitochondrial disease in cardiac tissue.
However, in bone marrow and blood, the results were opposite. The supplement caused an imbalance in cellular chemistry, with too much of certain molecules (NADH and NADPH) building up. This disrupted the normal process of making new red blood cells, worsening anemia, a condition where the body doesn’t have enough healthy red blood cells to carry oxygen.
The researchers also found that the supplement interfered with the production of heme, a critical component of hemoglobin (the protein that carries oxygen in blood). This explains why blood cell production suffered even though the heart benefited.
The supplement caused changes in amino acids, nucleotides, and folate levels in bone marrow, all molecules needed for cells to divide and mature properly. These chemical imbalances specifically harmed the development of red blood cells, which need to divide many times before becoming mature. The heart, which doesn’t need to make new cells, wasn’t affected by these problems.
Previous research has shown that NAD+ boosting helps with aging and age-related diseases in many tissues. This study confirms that benefit in the heart but reveals a critical limitation: the same mechanism that helps non-dividing cells can harm rapidly dividing cells like those in bone marrow. This suggests that earlier studies focusing only on heart or brain benefits may have missed important side effects.
This research was conducted in mice, not humans, so results may not directly translate to people. The study didn’t test different doses or treatment durations to see if lower amounts might help the heart without harming blood cells. Additionally, the specific genetic mutation in these mice may not represent all types of mitochondrial disease in humans. The study also didn’t explore whether other NAD+-boosting supplements have the same effects.
The Bottom Line
Do not take NAD+-boosting supplements (like nicotinamide riboside) without medical supervision, especially if you have blood disorders, anemia, or mitochondrial disease. If you’re considering these supplements for heart health or anti-aging, consult your doctor first and ask about potential effects on blood cell production. (Confidence: Moderate, based on animal research; human studies needed)
People with mitochondrial diseases, anemia, or blood disorders should be especially cautious. Anyone considering NAD+-boosting supplements for anti-aging or heart health should discuss this research with their doctor. Researchers developing new treatments for mitochondrial disease should consider tissue-specific effects. Healthy people without blood disorders may have lower risk, but long-term safety data in humans is still limited.
In the mice studied, the harmful effects on blood cells appeared alongside the beneficial heart effects, suggesting problems could develop relatively quickly with regular supplementation. Improvements in heart function also appeared relatively rapidly. In humans, effects would likely take weeks to months to become noticeable, but this hasn’t been tested.
Frequently Asked Questions
Is nicotinamide riboside safe to take as an anti-aging supplement?
A 2026 study found that while NR improved heart function in mice with mitochondrial disease, it worsened blood cell production and anemia. Long-term safety in healthy humans remains unknown. Consult your doctor before starting, especially if you have blood disorders.
Can NAD+ boosting supplements help with heart disease?
Research shows NR improved heart contractility and reduced stress markers in diseased hearts. However, the same supplement harmed blood cell production in the same mice, suggesting benefits in one organ don’t guarantee safety overall. Medical supervision is essential.
What are the side effects of taking NAD+ precursor supplements?
This study revealed that NAD+ boosting can impair red blood cell maturation, potentially worsening anemia and causing fatigue, shortness of breath, and pale skin. Effects on other tissues in humans haven’t been fully studied. Report any symptoms to your doctor.
Who should avoid NAD+-boosting supplements based on this research?
People with anemia, blood disorders, or mitochondrial disease should avoid these supplements without medical approval. The research shows they can worsen blood cell production. Anyone considering them should get blood work done first and discuss risks with their healthcare provider.
Does this mouse study mean NAD+ supplements are dangerous for humans?
This animal research suggests caution is warranted, but doesn’t prove danger in humans. However, it highlights that NAD+ boosting affects different tissues differently. Human studies are needed before recommending these supplements widely, especially for long-term use.
Want to Apply This Research?
- If a user is considering or taking NAD+-boosting supplements, track energy levels (1-10 scale daily), shortness of breath, and any signs of anemia (fatigue, pale skin, dizziness) weekly. Also note heart-related symptoms like chest discomfort or irregular heartbeat.
- Before starting any NAD+-boosting supplement, users should log their current blood work results (especially hemoglobin and red blood cell count) in the app and set a reminder to discuss this research with their doctor. After consultation, they can track whether symptoms improve or worsen.
- Create a monthly check-in where users rate heart health symptoms, energy, and blood-related symptoms (fatigue, shortness of breath). If taking supplements, encourage quarterly blood work to monitor red blood cell counts and hemoglobin levels, logging results in the app to share with healthcare providers.
This research was conducted in mice with a specific genetic form of mitochondrial disease and has not been tested in humans. NAD+-boosting supplements are not FDA-approved medications. Before starting any supplement, especially if you have heart disease, blood disorders, anemia, or mitochondrial disease, consult your healthcare provider. Do not stop or change any prescribed medications based on this information. This article is for educational purposes and should not replace professional medical advice.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.
