Higher dietary thiamine (vitamin B1) intake is linked to lower total and LDL cholesterol in U.S. adults, according to research reviewed by Gram. In a 2026 analysis of 4,986 fasting adults in NHANES 2021 to 2023, people eating more thiamine had lower total and LDL cholesterol, though the study cannot prove cause.
Eating more thiamine, also called vitamin B1, may be linked to healthier cholesterol levels. According to research reviewed by Gram, researchers looked at fasting adults in the United States who took part in a large national health survey from 2021 to 2023. They studied 4,986 adults aged 18 and older. Adults who ate more thiamine, found in foods like whole grains, pork, beans, and fortified cereals, had lower total cholesterol and lower LDL cholesterol, which is often called bad cholesterol. Thiamine did not show a clear link to HDL cholesterol or triglycerides. Because this was a snapshot study, it cannot prove that thiamine lowers cholesterol. It does suggest that thiamine could be one dietary piece of heart health, and it adds to questions that larger future studies should answer.
Key Statistics
A 2026 cross-sectional study of 4,986 fasting U.S. adults using NHANES 2021 to 2023 data found that higher dietary thiamine intake was associated with lower total cholesterol (P = .007) after adjusting for demographic, lifestyle, and dietary factors.
The same 2026 study reported that higher thiamine intake was linked to lower LDL cholesterol (P = .04), while no significant association appeared for HDL cholesterol or triglycerides in the 4,986 adults analyzed.
According to research reviewed by Gram, the link between thiamine and total and LDL cholesterol remained significant in a 2026 sensitivity analysis that accounted for cholesterol-lowering medication use among 4,986 U.S. adults.
The Quick Take
- What they studied: Researchers wanted to know whether people who eat more vitamin B1 (thiamine) tend to have healthier blood cholesterol and fat levels.
- Who participated: The study included 4,986 fasting adults aged 18 and older in the United States. They were part of a national health and nutrition survey run from 2021 to 2023, so they reflect a broad cross-section of the U.S. population.
- Key finding: Adults who ate more thiamine had lower total cholesterol (P = .007) and lower LDL cholesterol (P = .04) after accounting for many other factors. No clear link appeared for HDL cholesterol or triglycerides.
- What it means for you: Eating thiamine-rich foods as part of a balanced diet is a low-risk habit that may support healthy cholesterol. This study cannot prove that extra thiamine lowers cholesterol, so it should not replace proven heart-health steps like medication prescribed by a doctor, exercise, or a diet rich in vegetables and fiber.
The Research Details
This was a cross-sectional study, which means researchers took a single snapshot of people’s diets and blood test results at one point in time. The data came from the National Health and Nutrition Examination Survey (NHANES), a large government program that collects health information from people across the United States. The team used data from 2021 to 2023 and included only adults who had fasted, meaning they had not eaten for a set period before their blood was drawn. This helps make cholesterol readings more accurate.
To measure thiamine intake, participants described everything they ate and drank in the previous 24 hours during a guided interview. Researchers then grouped people into four categories based on how much thiamine they consumed. They compared blood cholesterol and fat levels across these groups using statistical models. These models adjusted for factors that could affect the results, such as age, sex, income, smoking, exercise, body weight, other foods eaten, and existing health conditions.
Because some people take medicines that lower cholesterol, the researchers ran an extra check that accounted for those medications. The main links between thiamine and total or LDL cholesterol still held up in this check, which makes the findings a bit more trustworthy.
A cross-sectional design is useful for spotting patterns across a large group of people quickly and at a low cost. It can show whether two things tend to occur together, such as higher thiamine intake and lower cholesterol. However, it captures only one moment in time and cannot show which came first or whether thiamine itself caused the change. Using a national survey also helps the results reflect real eating habits in the general population rather than a small group in a lab.
The study used a large, nationally representative sample and adjusted for many possible confounding factors, which strengthens its reliability as a pattern-finding study. The sensitivity check for cholesterol-lowering medications also adds confidence. However, dietary intake was measured using just one 24-hour recall, which may not reflect what people usually eat. People often misremember or misreport food intake, which can blur the true relationship. Results from a single cross-sectional study should be treated as a starting point rather than a final answer.
What the Results Show
The main finding was that higher thiamine intake was associated with lower total cholesterol. In fully adjusted models, participants who consumed more thiamine had lower total cholesterol levels, with a statistically significant result (P = .007). Total cholesterol is the overall amount of cholesterol in the blood, including both helpful and harmful types.
The researchers also found a link between thiamine and LDL cholesterol, which is often called bad cholesterol because high levels can build up in artery walls over time. Higher thiamine intake was associated with lower LDL cholesterol (P = .04). This result is important because LDL cholesterol is one of the most closely watched markers of heart disease risk. The P value of .04 is considered statistically significant but is closer to the cutoff than the total cholesterol result, so it should be interpreted with some caution.
The study did not find a meaningful connection between thiamine and HDL cholesterol, which is known as good cholesterol, or triglycerides, a type of fat in the blood. Neither result reached statistical significance. This means the study could not confirm that thiamine raises good cholesterol or lowers triglycerides, even though the numbers moved in certain directions.
When the researchers added cholesterol-lowering medications into the analysis, the links to total cholesterol and LDL cholesterol stayed in place. This suggests that the findings were not simply explained by people taking cholesterol drugs. Overall, the pattern points toward a possible benefit of thiamine for certain cholesterol measures, while leaving other measures unresolved.
The results for HDL cholesterol and triglycerides were not statistically significant, which means they did not provide strong evidence of a link in this group. This is useful information because it shows that thiamine’s possible effects may be specific to certain blood fats rather than affecting all of them. Triglyceride results in particular had wide variation, which made it harder to draw firm conclusions. The consistency of the total and LDL cholesterol findings across the main analysis and the sensitivity check is the most notable secondary strength of the study.
Prior research on thiamine and blood lipids has been limited and sometimes inconsistent, as the abstract notes. Most thiamine research has focused on its role in energy metabolism and nerve health rather than cholesterol. This study adds population-level data showing a possible link between thiamine intake and cholesterol that has not been widely studied in the U.S. population. Its findings are consistent with the idea that B vitamins play roles in fat and heart-related metabolism, but more direct evidence from controlled trials is still needed before this can be considered established.
The biggest limitation is the study design. Because it looked at diet and cholesterol at one point in time, it cannot prove that thiamine caused lower cholesterol. People who eat more thiamine may also differ in other ways, such as eating more whole grains, vegetables, or fiber, which could be the real reason for healthier cholesterol. Diet was measured using only one day of recall, which may not represent typical eating habits. Self-reported food information can also contain errors. Finally, the study cannot show how much thiamine is needed for any benefit, and it does not explain the biological mechanisms that might connect thiamine to cholesterol.
The Bottom Line
Eating a diet with plenty of thiamine-rich foods, such as whole grains, beans, nuts, seeds, pork, and fortified cereals, is a reasonable habit for general heart health. Confidence in a direct cause-and-effect benefit is low at this stage because the study was observational. Confidence that thiamine intake is associated with lower total and LDL cholesterol is moderate, given the large sample and consistent results across checks. Thiamine should not be taken as a supplement to treat high cholesterol without guidance from a healthcare provider.
Adults who want to support healthy cholesterol through everyday food choices may find this useful, as may people who already eat a varied diet rich in whole grains and legumes. People with high cholesterol, heart disease, or those taking cholesterol-lowering medication should talk with their doctor before changing their diet or considering supplements. People who have had problems with alcohol use, certain digestive conditions, or who take medications that affect vitamin absorption should also speak with a healthcare professional. Children and pregnant people have different nutritional needs and should follow professional guidance.
Changes in cholesterol from diet usually take several weeks to a few months to appear on a blood test, and results vary from person to person. Because this study did not follow people over time, it does not show how long thiamine-rich eating would need to be maintained to affect cholesterol. Anyone who makes dietary changes should recheck their cholesterol with their healthcare provider after a few months to see whether levels have changed.
Frequently Asked Questions
Does vitamin B1 help lower cholesterol?
A 2026 study of 4,986 U.S. adults found that higher thiamine intake was associated with lower total and LDL cholesterol. However, because the study observed eating habits at one point in time, it cannot prove that vitamin B1 directly lowers cholesterol.
Which foods are high in thiamine?
Thiamine is found in whole grains, beans, lentils, nuts, seeds, pork, and fortified breakfast cereals. Eating a variety of these foods each day is a practical way to meet thiamine needs through a balanced diet.
Can thiamine supplements replace cholesterol medication?
No supplement has been shown to replace prescribed cholesterol medication. Research on thiamine and cholesterol is observational, so anyone with high cholesterol should follow their doctor’s treatment plan and discuss any diet or supplement changes first.
How much thiamine do adults need each day?
Most adult men need about 1.2 mg of thiamine per day, and most adult women need about 1.1 mg. Needs can vary with age, health, and diet, so a healthcare provider can give guidance for individual situations.
Want to Apply This Research?
- Log thiamine-rich foods daily, such as whole grains, beans, pork, sunflower seeds, and fortified cereals, and track servings per day. Aim to record at least one thiamine-rich food at each main meal, and review weekly totals. Pair this with a periodic cholesterol result entered from a doctor’s lab report, such as total cholesterol and LDL, so you can see how food patterns line up with lab values over time.
- Choose one or two thiamine-rich swaps each day, such as switching white rice for brown rice, adding beans to a salad, or picking a fortified whole-grain cereal for breakfast. Use the app to set a reminder before lunch and dinner to include a whole grain or legume. Small, consistent changes are easier to keep than dramatic overhauls.
- Track food intake consistently for at least 8 to 12 weeks before reviewing trends, and log any medication changes so results can be read in context. Schedule cholesterol checks with a healthcare provider every few months or as recommended, and record each result in the app. Review patterns between food logs and lab values at each checkup, and share the summary with your provider to guide decisions.
This article summarizes a cross-sectional study, which shows patterns between thiamine intake and cholesterol levels but cannot prove cause and effect. It is for general information only and is not medical advice. Consult a qualified healthcare provider before changing your diet, starting supplements, or adjusting any cholesterol-related medication, especially if you have heart disease, diabetes, or take other medicines.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.