The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.The recommended daily intake by the U.S. Food and Nutrition Board of the Institute of Medicine for men more than 18 years old is 90 milligrams of vitamin C daily; for women more than 18 years old, it is 75 milligrams daily; for pregnant women more than 18 years old, it is 85 milligrams daily; and for breastfeeding women more than 18 years old, it is 120 milligrams daily. Recently, some experts have questioned whether the recommended daily intake should be raised. Others have recommended an additional 35 milligrams daily intake in some individuals, such as smokers.
The upper limit of intake (UL) should avoid exceeding 2,000 milligrams daily in men or women more than 18 years old (including pregnant or breastfeeding women). Vitamin C administered by mouth or injection is effective for curing scurvy. 100-250 milligrams of vitamin C was given by mouth four times daily for one week. Some experts have recommended 1-2 grams daily for two days, followed by 500 milligrams daily for one week. Symptoms should begin to improve within 24-48 hours, and be completely cured within seven days. Treatment should be under strict medical supervision. For asymptomatic vitamin C deficiency, lower daily doses may be used. For antioxidant effects, 200-1,000 milligrams of vitamin C has been given daily for four weeks to a year; 300-3,000 milligrams of vitamin C has been injected into the vein, from a single dose to a duration of eight weeks. For breast cancer prevention, 500 milligrams of vitamin C has been taken by mouth daily. For cancer prevention, 120-2,000 milligrams of vitamin C has been taken by mouth daily for six to eight years.
For preventing the common cold in people in extreme environments, 200 milligrams or more of vitamin C has been taken by mouth daily for up to 14 days. For preventing the common cold in general, 30-3,000 milligrams of vitamin C has been taken by mouth daily for two weeks to eight winters. For treating the common cold, 200 milligrams to 3 grams have been taken by mouth daily for three to five days or longer. For preventing complex regional pain syndrome in people with wrist fractures, 500 milligrams of vitamin C has been taken by mouth daily for 50 days. For fertility, 750 milligrams of vitamin C has been taken by mouth daily for six months. For heart conditions, 2 grams of vitamin C has been given by mouth before surgery, followed by 1 gram daily for five days. For H. pylori infection, 400-1,000 milligrams of vitamin C has been given by mouth daily for up to seven weeks. For high blood pressure, 60-4,000 milligrams of vitamin C has been given by mouth daily for 6-16 weeks.
For kidney disease, 3 grams of vitamin C was given by mouth before the kidney-toxic procedure, then 2 grams after the procedure in the evening and again the following morning; 100-200 milligrams of vitamin C has been taken by mouth daily. For liver disease, 120-3,000 of milligrams vitamin C has been taken by mouth daily for one day to six months; effectiveness on liver disease was lacking. For life extension, 60-2,000 milligrams of vitamin C has been taken by mouth daily for one month to 9.5 years. For preventing nitrate tolerance, 3-6 grams of vitamin C has been taken by mouth daily. For pregnancy, 100-1,000 milligrams of vitamin C has been taken by mouth up to four times daily during pregnancy until delivery. For prostate cancer, 500 milligrams of vitamin C has been taken by mouth daily for an average of eight years. For anemia, 200-300 milligrams of vitamin C has been injected into the vein three times weekly, for 3-6 months. For preventing gout, 500-1,500 milligrams of vitamin C from food and/or supplements has been taken daily.
For skin aging, preparations containing 5-10% vitamin C were applied on the skin daily. The recommended daily intake by the U.S. Food and Nutrition Board of the Institute of Medicine for infants 0-12 months old is the amount of vitamin C in human milk; for children 1-3 years old, it is 15 milligrams; for children 4-8 years old, it is 25 milligrams; for children 9-13 years old, it is 45 milligrams; and for adolescents 14-18 years old, it is 75 milligrams for boys and 65 milligrams for girls. The tolerable upper intake levels (UL) for vitamin C are 400 milligrams daily for children 1-3 years old; 650 milligrams daily for children 4-8 years old; 1,200 milligrams daily for children 9-13 years old; and 1,800 milligrams daily for adolescents and pregnant and lactating females 14-18 years old. For metabolic abnormalities, 100 milligrams of vitamin C has been taken by mouth. For scurvy or vitamin C deficiency in children, 100-300 milligrams of vitamin C has been taken by mouth daily in divided doses for two weeks.
Older or larger children may require doses closer to adult recommendations. If vitamin C is unavailable, orange juice may be used. Symptoms should begin to improve within 24-48 hours, with resolution within seven days. Treatment should be under strict medical supervision. This evidence-based monograph was prepared by The Natural Standard Research CollaborationVitamin C is crucial for children's good health and development. Read on to find out how much vitamin C your child needs, which sources are the best, and how to avoid getting too little or too much.Why vitamin C is importantVitamin C helps form and repair red blood cells, bones, and tissues. It helps your child's gums stay healthy and strengthens your child's blood vessels, minimizing bruising from falls and scrapes. In addition, vitamin C helps cuts and wounds heal, boosts the immune system, and keeps infections at bay. And it helps the body absorb iron from food sources.Ages 1 to 3 years: 15 milligrams (mg) dailyAges 4 to 8: 25 mg dailyThis vitamin is available in so many foods that deficiencies are extremely rare.
Children who are very picky eaters and don't eat a lot of fruits and vegetables may not get enough vitamin C. Also, children exposed to secondhand smoke need more vitamin C to repair cell damage from cigarettes.If you're concerned that your child doesn't get enough vitamin C, ask your child's doctor whether you need to boost your child's intake.Your child doesn't have to get enough vitamin C every day. Instead, aim to get the recommended amount as an average over the course of a few days or a week.Brightly colored fruits and vegetables are great sources of vitamin C.The amount of vitamin C in a food varies somewhat, depending on the size of the fruit or vegetable.Kids may eat more or less than the amounts shown, given their age and appetite. Estimate the nutrient content accordingly.Vitamin C is water soluble, so any excess is flushed from the body in your child's urine. However, megadoses can still cause nausea, diarrhea, kidney stones, and gastritis (inflammation of the stomach lining).