Researchers studied people with oral lichen planus (OLP), a condition causing painful sores in the mouth, to see if they had hidden nutritional deficiencies. They compared three groups: people with OLP and normal-sized red blood cells, people with OLP overall, and healthy people without OLP. They found that people with OLP and normal red blood cells were more likely to have low iron, vitamin B12, and folic acid levels compared to healthy people. This suggests that people with mouth sores should get their nutrition checked, even if their red blood cells look normal under a microscope.

The Quick Take

  • What they studied: Whether people with a painful mouth condition called oral lichen planus have hidden nutritional deficiencies that don’t show up in standard blood tests
  • Who participated: Three groups of people: 474 with mouth sores and normal red blood cell size, 588 with mouth sores overall, and 588 healthy people without mouth sores
  • Key finding: People with mouth sores had 2-3 times higher rates of iron, B12, and folic acid deficiencies compared to healthy people, even when their red blood cells looked normal in size
  • What it means for you: If you have painful mouth sores (oral lichen planus), ask your doctor to check your iron, B12, and folic acid levels, because you might be deficient even if you feel okay. This is especially important because fixing these deficiencies might help your mouth heal better.

The Research Details

This was a cross-sectional study, which means researchers took a snapshot in time by comparing three different groups of people at the same moment. They measured blood tests in all three groups to look for nutritional deficiencies and special antibodies that suggest stomach problems. The researchers specifically looked at people whose red blood cells were normal-sized (between 80-99.9 fL), which is important because usually when people lack nutrients, their red blood cells get smaller or larger. By focusing on people with normal-sized red blood cells, the researchers could find hidden deficiencies that might be missed by doctors who only look at red blood cell size.

This study matters because it shows that people with mouth sores might have serious nutritional problems even when standard tests look normal. Many doctors might miss these deficiencies if they only check red blood cell size. Finding these hidden problems is important because fixing them could help people feel better and heal their mouth sores faster.

This study included a large number of people (1,650 total), which makes the results more reliable. The researchers compared the mouth sore group to both healthy people and other mouth sore patients, which helps show that the nutritional problems are really connected to the condition. However, the study only took a snapshot in time, so we can’t be completely sure that the nutritional deficiencies caused the mouth sores or vice versa. The study was published in a dental journal, which is appropriate for this topic.

What the Results Show

Among people with mouth sores and normal red blood cells, about 14% had low hemoglobin (the protein that carries oxygen in blood), 13% had low iron, 4% had low vitamin B12, and 2% had low folic acid. Additionally, 16% had high homocysteine (an amino acid that can be harmful at high levels), and 20% had special antibodies suggesting stomach problems. When compared to healthy people, all of these problems were significantly more common in the mouth sore group. For example, low iron was about 8 times more common, low B12 was about 3 times more common, and low folic acid was about 2 times more common in people with mouth sores.

The study also found that people with mouth sores had higher levels of homocysteine (an amino acid that can damage blood vessels when too high) and were more likely to have antibodies against stomach cells. These antibodies suggest that some people with mouth sores might have stomach problems that prevent them from absorbing nutrients properly. Interestingly, people with mouth sores and normal red blood cells actually had fewer nutritional deficiencies than people with mouth sores overall, suggesting that red blood cell size might hide some of the nutritional problems.

Previous research has suggested that nutritional deficiencies might be connected to mouth sores, but this study is important because it shows these deficiencies exist even when red blood cells look normal. This finding challenges the idea that doctors can rely only on red blood cell size to detect nutritional problems in people with mouth sores. The connection to stomach antibodies is also interesting because it suggests that poor nutrient absorption in the stomach might be part of the problem.

This study only looked at people at one point in time, so we can’t prove that nutritional deficiencies cause mouth sores or that fixing them will cure the condition. The study doesn’t tell us whether treating these deficiencies actually helps people feel better or heal faster. We also don’t know if these findings apply to people in other countries or different ethnic groups, since the study population wasn’t described in detail. Finally, the study can’t explain why some people with mouth sores have these deficiencies while others don’t.

The Bottom Line

If you have oral lichen planus (painful mouth sores), ask your doctor to check your iron, vitamin B12, and folic acid levels, even if your red blood cells look normal. This is a moderate-confidence recommendation based on this research. Also ask about your homocysteine level and whether you might have stomach absorption problems. If deficiencies are found, work with your doctor to treat them through diet or supplements.

People with oral lichen planus should definitely pay attention to this research. Dentists and doctors who treat mouth sores should consider checking for these nutritional deficiencies in their patients. This is less relevant for people without mouth sores, though anyone with unexplained fatigue or other symptoms might want to discuss nutritional testing with their doctor.

If you do have nutritional deficiencies and start treatment, you might notice improvements in your mouth sores within 4-12 weeks, but this varies by person. Some people might feel more energetic within 2-4 weeks of starting supplements. However, this study doesn’t prove that treating deficiencies will cure mouth sores, so talk to your doctor about realistic expectations.

Want to Apply This Research?

  • Track your mouth sore pain level daily (1-10 scale) and note any dietary changes or supplement use. Also track energy levels and any digestive symptoms, since stomach problems might be connected to nutrient absorption.
  • Use the app to log iron-rich foods (red meat, beans, spinach), B12 sources (eggs, dairy, fortified cereals), and folic acid sources (leafy greens, legumes, asparagus) to ensure you’re getting enough nutrients. Set reminders to take any supplements your doctor recommends.
  • Check in monthly with your doctor about your mouth sore symptoms and how you’re feeling overall. Use the app to track whether your symptoms improve as you address nutritional deficiencies. Keep records of your blood test results over time to see if your levels are improving.

This research suggests a connection between mouth sores and nutritional deficiencies, but it does not prove that treating deficiencies will cure oral lichen planus. Do not start taking supplements or make major dietary changes without talking to your doctor first. If you have oral lichen planus or suspect you have nutritional deficiencies, consult with a healthcare provider for proper testing and personalized treatment recommendations. This information is for educational purposes only and should not replace professional medical advice.