Studies have pointed out that if you eat more than 3,000 mg of vitamin C a day, intestinal bacteria will metabolize the unabsorbed vitamin C, causing osmotic pressure disorders and diarrhea. In addition, the metabolite of vitamin C is oxalic acid, which may increase the risk of hyperoxalemia, leading to kidney stones. In 2013, a study explored the problem of kidney stones caused by excessive intake of vitamin C. The study found that men who regularly take vitamin C supplements have twice the risk of kidney stones. Therefore, scholars have set a daily intake limit to avoid kidney stone problems caused by taking too much vitamin C.
2. how much vitamin C is appropriate to eat a day
Healthy adults consume 100 mg of vitamin C daily, the white blood cells will become saturated, and vitamin C will begin to be excreted in the urine; daily intake of 200 mg means that the concentration of vitamin C in the blood plasma can reach 80% of the saturation level. Daily intake of 400 mg is almost saturated. This means that there is really no need to take too much vitamin C, because no matter how much you take, when the body reaches saturation, too much vitamin C will be excreted in the urine. The recommended daily intake for adults is 100 mg, for pregnant women about 120 mg per day, and for breastfeeding mothers is 140 mg per day. In fact, you only need to eat half a guava or a kiwi fruit to reach the recommended intake.
