Scientists are raising important questions about how much folic acid we’re adding to foods like bread and cereals. While folic acid helps prevent birth defects, new research suggests that too much of it—especially the synthetic kind—might cause problems for the brain and nervous system, particularly if someone doesn’t have enough vitamin B12. Experts are calling for a more careful approach to food fortification that considers both the benefits and potential risks, especially for children and teenagers whose brains are still developing.
The Quick Take
- What they studied: Whether the current practice of adding synthetic folic acid to foods is safe and effective, and whether we should switch to natural folate sources instead
- Who participated: This is a commentary letter reviewing existing research rather than a study with human participants. It builds on previous scientific findings about folic acid, vitamin B12, and brain health
- Key finding: Synthetic folic acid (the kind added to foods) may be different from natural folates found in foods, and too much synthetic folic acid could potentially harm the nervous system, especially when vitamin B12 levels are low
- What it means for you: Current food fortification policies may need adjustment, but this doesn’t mean you should avoid fortified foods. Instead, it suggests that scientists and policymakers should study this more carefully and consider safer approaches to preventing birth defects
The Research Details
This is a comment letter—a type of scientific writing where experts respond to and expand on previous research. The authors reviewed existing studies about folic acid, natural folates, vitamin B12, and how these nutrients affect the brain and nervous system. Rather than conducting new experiments, they analyzed what other scientists have already discovered and identified gaps in our knowledge.
The authors focused on several key areas: the differences between synthetic folic acid (made in laboratories and added to foods) and natural folates (found in foods like leafy greens and beans), the effects of too much folic acid on developing brains in children and teenagers, and the practical challenges of changing how countries add nutrients to foods.
This type of review is valuable because it brings together information from many studies and helps scientists and policymakers understand what we know and what we still need to learn.
Understanding the difference between synthetic and natural forms of nutrients is important because they may work differently in our bodies. This research approach helps identify potential problems with current policies before they cause widespread harm. By examining long-term effects and practical challenges, the authors provide a more complete picture than any single study could offer.
This is a commentary by experts in neurology and nutrition, published in a respected scientific journal. However, because it’s a review of existing research rather than a new study, it doesn’t provide direct experimental evidence. The strength of the conclusions depends on the quality of the studies being reviewed. Readers should note that this represents expert opinion based on current evidence, not definitive proof that folic acid fortification is harmful.
What the Results Show
The authors identify an important distinction: synthetic folic acid (added to foods) may behave differently in the body than natural folates (found in whole foods). They emphasize that while folic acid fortification has successfully reduced neural tube defects (serious birth defects affecting the brain and spine), we may not fully understand the long-term effects of consuming high amounts of synthetic folic acid.
A critical concern highlighted is the interaction between folic acid and vitamin B12. When someone has low B12 levels and consumes excess folic acid, this combination may potentially cause problems with the nervous system. This is particularly worrying because B12 deficiency is not uncommon in certain populations.
The authors stress that children and teenagers are especially vulnerable because their brains are still developing. We don’t have enough long-term studies examining whether high folic acid exposure during these critical years could cause problems later in life.
Another significant finding involves epigenetics—how nutrients our ancestors consumed might affect our genes and health. The authors call for more research into whether a parent’s or grandparent’s folate status could influence a child’s health through changes in how genes are expressed.
The authors also discuss the practical challenges of changing food fortification policies worldwide. Switching from synthetic folic acid to natural folate forms would require significant changes to food manufacturing, regulatory approval in many countries, and substantial costs. These real-world obstacles mean that even if scientists agree on better approaches, implementing them globally would be complicated and time-consuming.
The review highlights that current safety limits for folic acid intake may need to be reconsidered based on emerging evidence about potential neurological effects.
This commentary builds on a comprehensive review by Edward H. Reynolds about folate, B12, and nervous system health. While supporting Reynolds’ insights about potential harms from excess folic acid, the authors expand the discussion to include more recent concerns about synthetic versus natural forms, effects on developing brains, and the practical challenges of policy change. This represents an evolution in scientific thinking—moving from simply adding more folic acid to prevent birth defects toward a more nuanced understanding of optimal folate nutrition.
This is a commentary letter, not original research, so it doesn’t provide new experimental data. The conclusions depend on how well previous studies were conducted and whether they’ve been properly interpreted. The authors acknowledge that much of what they discuss requires further investigation—we don’t yet have definitive proof that current folic acid fortification causes harm, only evidence suggesting we should study it more carefully. Additionally, the practical and economic barriers to changing global fortification policies mean that even if problems are identified, solutions may take many years to implement.
The Bottom Line
Based on current evidence, experts suggest: (1) Continue fortifying foods with folic acid to prevent birth defects, as the benefits are well-established—this is a moderate to high confidence recommendation; (2) Conduct more research comparing synthetic folic acid to natural folates—moderate confidence; (3) Study the long-term effects of high folic acid exposure in children and teenagers—moderate confidence; (4) Ensure adequate vitamin B12 intake, especially for people at risk of deficiency—high confidence; (5) Consider gradually shifting toward natural folate fortification where feasible—low to moderate confidence due to practical challenges.
Pregnant women and those planning pregnancy should care about this research because folic acid prevents serious birth defects—the benefits are clear and important. Parents of children and teenagers should be aware that scientists are studying whether very high folic acid exposure during development could be problematic. People with vitamin B12 deficiency should pay attention because the combination of low B12 and high folic acid may be particularly concerning. Policymakers and food manufacturers need to consider these findings when making decisions about food fortification. People eating a diet rich in natural folates (leafy greens, legumes, asparagus) don’t need to worry—natural folates appear safer than synthetic versions.
Birth defect prevention from folic acid happens during pregnancy, so benefits appear within months. However, potential problems from excess folic acid exposure would likely develop over years or decades, making them harder to detect. Changes to food fortification policies, if implemented, would take several years to complete globally.
Want to Apply This Research?
- Track daily folate intake from both fortified foods and natural sources (leafy greens, beans, asparagus, broccoli). Log the type of folate source (synthetic fortified foods vs. whole food sources) and monitor energy levels, cognitive function, and any neurological symptoms weekly
- Increase consumption of natural folate-rich whole foods while being mindful of total synthetic folic acid intake from fortified products. Users can set a goal to get 50% of folate from whole food sources and track this ratio in the app
- Implement a 12-week tracking period where users log folate sources, symptoms, and overall wellness. Create alerts for users to check B12 levels annually, especially if consuming high amounts of fortified foods. Generate monthly reports showing folate source distribution and correlations with reported symptoms or energy levels
This commentary represents expert analysis of existing research and does not constitute medical advice. Folic acid fortification has proven benefits in preventing serious birth defects, and pregnant women and those planning pregnancy should continue consuming adequate folic acid as recommended by their healthcare provider. The concerns raised about excess synthetic folic acid are based on emerging evidence and require further investigation. Do not change your diet or supplementation without consulting your doctor, especially if you are pregnant, planning pregnancy, have vitamin B12 deficiency, or have neurological conditions. If you have concerns about your folate or B12 levels, ask your healthcare provider about testing and personalized recommendations.