Scientists discovered that your DNA plays a big role in how your body processes choline, an important nutrient found in foods like eggs and fish. In a study of 37 healthy men, researchers gave them choline in two different forms and found that people with different genetic variations responded differently to each type. Some people’s bodies broke down choline faster, while others stored it differently, depending on their genes. This research suggests that in the future, doctors might be able to recommend the best type of choline for each person based on their DNA, rather than giving everyone the same advice.

The Quick Take

  • What they studied: Whether different types of choline supplements work differently in people’s bodies depending on their genes
  • Who participated: 37 healthy adult men who each tried two different forms of choline in a carefully controlled study where neither they nor the researchers knew which type they were getting
  • Key finding: People with different genetic variations responded differently to the two types of choline tested. Some genes made people break down choline faster, while other genes affected how their bodies stored and used it.
  • What it means for you: Your genes may influence how well you absorb and use choline from supplements or food. However, this is early research in a small group of men, so you shouldn’t change your diet based on this alone. Talk to your doctor before making any changes.

The Research Details

This was a randomized controlled trial, which is one of the strongest types of studies. The researchers gave 37 healthy men a meal containing 600 mg of choline in one of two forms: regular choline (called choline bitartrate) or a form called phosphatidylcholine that’s found naturally in foods like eggs. Each man tried both forms on different days, and neither the participants nor the researchers knew which form they were getting each time—this is called a “blind” study and helps prevent bias. The researchers collected urine samples before and after the meal to measure how the body processed the choline.

The scientists also tested each participant’s DNA for four specific genetic variations known to affect how the body handles choline. These genetic variations are common in the population, meaning many people have them. By comparing how people with different genetic variations responded to each type of choline, the researchers could see if genes influenced the results.

This approach is important because it looks at the interaction between genes and nutrients, which is a growing area of nutrition science called “precision nutrition.”

Understanding how genes affect nutrient processing is important because it explains why people respond differently to the same foods and supplements. If we can identify which genetic variations affect choline metabolism, doctors might eventually be able to recommend personalized nutrition advice based on a person’s DNA. This could make nutrition advice more effective and help people get the right nutrients for their individual bodies.

This study has several strengths: it used a randomized, blinded design which reduces bias; it measured actual metabolites in urine rather than relying on self-reporting; and it looked at specific genetic variations with known biological functions. However, the study was small (only 37 men) and only included healthy adult males, so results may not apply to women, older adults, or people with health conditions. The study only measured urine metabolites over 6 hours, which is a short time window. Larger studies in more diverse populations would be needed to confirm these findings.

What the Results Show

The main finding was that different types of choline produced different patterns in the body’s metabolites (the chemical byproducts of metabolism). When people ate regular choline, their bodies absorbed and processed it differently than when they ate phosphatidylcholine, which is a more complex form of choline found naturally in foods.

The genetic variations made a significant difference in how people responded. For example, people with a certain variation in the CHDH gene broke down choline more slowly, meaning choline stayed in their bodies longer. This suggests their bodies were more efficient at using the choline they consumed.

Other genetic variations affected how the body partitioned, or divided up, the choline between different metabolic pathways. This means some people’s bodies preferentially used choline for one purpose, while other people’s bodies used it for different purposes, depending on which genetic variation they had.

These differences were statistically significant, meaning they were unlikely to be due to chance, though the study size was small.

The study also found that the two different forms of choline created distinct metabolic signatures—unique patterns of chemical byproducts in the urine. This suggests that the body processes free choline and phosphatidylcholine through somewhat different pathways. The genetic variations influenced not just how much choline was processed, but also which metabolic pathways were used, indicating that genes control multiple steps in choline metabolism.

Previous research had identified the four genes studied here as being involved in choline metabolism, but this is one of the first studies to look at how genetic variations in these genes affect responses to different forms of choline. The findings support the emerging concept of precision nutrition—the idea that genetic differences explain why people respond differently to the same nutrients. This research adds to growing evidence that one-size-fits-all nutrition recommendations may not work for everyone.

This study has important limitations to consider. First, it only included 37 healthy adult men, so the results may not apply to women, children, older adults, or people with health conditions. Second, the study only measured metabolites in urine over a 6-hour period, which is a short window and may not capture longer-term effects. Third, the study only looked at four genetic variations, but many other genes likely influence choline metabolism. Fourth, the study used a single dose of 600 mg of choline, so results may differ with different amounts. Finally, this was a short-term study, so we don’t know if these genetic differences matter for long-term health outcomes.

The Bottom Line

Based on this research, there are no specific recommendations to change your diet or supplement use yet. The findings are interesting but preliminary. If you’re interested in choline intake, focus on eating choline-rich foods like eggs, fish, chicken, and leafy greens rather than supplements. If you’re considering choline supplements, talk to your doctor first. Future research may eventually lead to personalized recommendations based on genetic testing, but we’re not there yet.

This research is most relevant to people interested in precision nutrition and personalized health. It may eventually matter for people considering choline supplements, particularly those with family histories of conditions related to choline metabolism. However, the findings are preliminary and shouldn’t influence most people’s current dietary choices. People with certain genetic conditions affecting choline metabolism should consult their doctors, as this research doesn’t yet provide clear guidance for them.

This is basic research that helps us understand how genes and nutrients interact. It’s not yet at the stage where it can predict how quickly you’d see health benefits from changing your choline intake. If personalized choline recommendations based on genetics do become available in the future, it would likely take several years of additional research to develop reliable tests and recommendations.

Want to Apply This Research?

  • Track daily choline intake from food sources (eggs, fish, poultry, dairy, nuts, leafy greens) by logging meals and noting the estimated choline content. Aim to track for 2-4 weeks to establish baseline intake patterns.
  • If interested in optimizing choline intake, users could set a goal to include one choline-rich food at each meal and track whether they meet this goal daily. For example: one egg at breakfast, fish at lunch, and chicken at dinner.
  • Monitor overall energy levels, cognitive function, and general wellbeing over 4-8 weeks while maintaining consistent choline intake from food sources. Note any changes in memory, focus, or mood. This provides personal feedback while waiting for more research to clarify individual genetic responses.

This research is preliminary and based on a small study of healthy adult men. The findings do not yet provide clear guidance for individual dietary choices or supplementation. Genetic variations in choline metabolism may affect nutrient processing, but this doesn’t mean you need to change your diet or take supplements based on this study alone. If you have concerns about your choline intake or are considering genetic testing for nutrition purposes, consult with your healthcare provider or a registered dietitian. This information is for educational purposes and should not replace professional medical advice.