| Trimethylamine-N-oxide (TMAO) is a gut microbiota–derived metabolite produced from dietary precursors such as choline, phosphatidylcholine, and carnitine. In cancer, the current literature points to TMAO as generally pro-tumorigenic in several solid-tumor settings, especially colorectal cancer, hepatocellular carcinoma, and possibly prostate cancer, where it has been linked to higher proliferation, migration, angiogenesis, EMT, and inflammatory signaling. Mechanistically, reported pathways include VEGFA-driven angiogenesis, PI3K/AKT, MAPK, oxidative/inflammatory stress, and metabolic reprogramming. However, the picture is not uniformly one-directional: in some immune-competent models, particularly triple-negative breast cancer and pancreatic cancer, TMAO has been reported to enhance antitumor immunity and improve response to checkpoint blockade. So the fairest summary is that TMAO is usually associated with cancer-promoting biology in tumor-cell–centric studies, but can be context-dependent when the immune microenvironment is considered
higher TMAO has been linked to several AD-relevant axes: neuroinflammation, vascular dysfunction, BBB/glymphatic impairment, oxidative stress, and amyloid/tau-associated pathology.
-high concentrations of polyphenols (e.g., resveratrol, catechins, quercetin, and quercetin-3-O-glucoside), which act synergistically to protect various target organs from elevated TMAO levels
-clinical studies demonstrated that high-dose atorvastatin (80 mg) or the combination of atorvastatin/ezetimibe or rosuvastatin can significantly reduce TMAO levels, likely due to their direct action on the TMAO-producing gut flora
-Gut dysbiosis → TMA/TMAO production
-Increase plant-forward foods and fiber to shift gut microbiota away from high TMA production.
-TMAO is cleared renally and rises with kidney impairment.
-Sunflower lecithin ≈ 3–5% choline by weight
Dietary choline intake ∼ 350 mg/d was associated with the lowest risk of clinical diagnosis of AD in older adults.
Health Canada Adequate level is 550mg/day for men and 425mg/day for females.
| Source | Typical serving | Choline/serving | Main choline form | TMAO relevance |
| ---------------------- | --------------: | --------------: | ------------------- | ------------------------------------------ |
| Egg yolk | 1 large yolk | ~125–150 mg | Phosphatidylcholine | High |
| Whole egg | 1 large | ~145–150 mg | Phosphatidylcholine | High |
| Beef liver | 3 oz | ~350+ mg | Mixed choline forms | High |
| Chicken liver | 3 oz | ~240–290 mg | Mixed | High |
| Salmon | 3 oz | ~70–90 mg | Mixed | Moderate; fish also contains TMAO directly |
| Beef | 3 oz | ~70–110 mg | Choline + carnitine | High TMAO relevance |
| Chicken breast | 3 oz | ~60–75 mg | Mixed | Moderate |
| Soy lecithin | 1 tbsp, ~7–10 g | ~200–500 mg | Phosphatidylcholine | Moderate–high, depends on dose |
| Sunflower lecithin | 1 tbsp, ~7–10 g | ~200–500 mg | Phosphatidylcholine | Moderate–high, depends on dose |
| Egg lecithin | 1 tbsp, ~7–10 g | ~400–900 mg | Phosphatidylcholine | High |
| High-PC lecithin | 1 g PC | ~130 mg choline | Phosphatidylcholine | High if taken daily |
| Soybeans, cooked | ½ cup | ~100 mg | Mixed | Moderate |
| Wheat germ | ¼ cup | ~50 mg | Mixed | Low–moderate |
| Milk | 1 cup | ~35–45 mg | Mixed | Low–moderate |
| Broccoli / cauliflower | 1 cup cooked | ~30–60 mg | Mixed | Low |
| Potato | 1 medium | ~25–45 mg | Mixed | Low |
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