Why do I feel nauseous after taking dietary supplements?

Most of the time when dietary supplements cause nausea, it is neither because the supplements are "harmful" nor because you have a special constitution. The core reasons are nothing more than irritating ingredients, incorrect taking methods, and product quality issues. A few of them are special reactions induced by underlying diseases or allergies. When I helped a friend with iron deficiency anemia adjust her supplement regimen a while ago, she first started taking ordinary ferrous sulfate tablets, and she would have acid reflux and vomiting half an hour after taking them. Later, she switched to amino acid chelated iron, which is more friendly to the stomach, and then changed to taking it with lunch. It was disgusting. The situation disappears immediately - fish oils such as this type of inorganic iron, high-dose B group, and uncoated fish oil are inherently irritating to the gastric mucosa. If you have a sensitive stomach and are used to eating on an empty stomach, then there will be no food buffer in the stomach, and you will feel nauseated and vomiting when the irritation occurs. There are also many people who are greedy for cheap and buy supplements that are late or unavailable. My former fitness teammates chipped in and bought some fish oil. After eating it once, I even vomited the chicken breast salad I just ate. After I opened the capsule and smelled it, there was a clear smell of irritation. This kind of supplement that has been oxidized and deteriorated is actually the body's self-protection when it stimulates gastrointestinal vomiting. Regarding this nausea reaction, the nutrition circle now has different views. Some researchers believe that this may also be an "excess signal" sent by the body. For example, the vitamin A and iron in your daily diet can already meet the needs, and you take high-dose compound supplements. If the intake exceeds the threshold of the body's needs, it will reduce the absorption of excess nutrients through nausea and vomiting. However, there is not enough large-scale clinical data to support this statement. More experts still prefer to first consider the issue of ingredient stimulation and taking methods. If you frequently feel vomiting after taking a certain supplement, first try changing it to taking it with meals. If you still feel uncomfortable, you can switch to a milder dosage form, such as enteric-coated fish oil, liquid iron, etc. If you still have a reaction after adjusting, don’t take it. Either check whether you are allergic to certain ingredients, or check whether you have basic gastrointestinal problems such as chronic gastritis or Helicobacter pylori infection. Don’t blindly blame the supplement and don’t force yourself to take it.