Age-related macular degeneration AMD , or the loss of central vision as people age, is one of the most common causes of vision loss in older people. Among people with AMD who are at high risk of developing advanced AMD, a supplement containing antioxidants , zinc, and copper with or without beta-carotene has shown promise for slowing down the rate of vision loss.
When children with vitamin A deficiency which is rare in North America get measles, the disease tends to be more severe. In these children, taking supplements with high doses of vitamin A can shorten the fever and diarrhea caused by measles.
These supplements can also lower the risk of death in children with measles who live in developing countries where vitamin A deficiency is common. Getting too much preformed vitamin A usually from supplements or certain medicines can cause dizziness, nausea , headaches, coma, and even death. High intakes of preformed vitamin A in pregnant women can also cause birth defects in their babies.
Women who might be pregnant should not take high doses of vitamin A supplements. Consuming high amounts of beta-carotene or other forms of provitamin A can turn the skin yellow-orange, but this condition is harmless.
High intakes of beta-carotene do not cause birth defects or the other more serious effects caused by getting too much preformed vitamin A. The daily upper limits for preformed vitamin A include intakes from all sources—food, beverages, and supplements—and are listed below. These levels do not apply to people who are taking vitamin A for medical reasons under the care of a doctor. Upper limits for beta-carotene and other forms of provitamin A have not been established.
Yes, vitamin A supplements can interact or interfere with medicines you take. Here are several examples:. Tell your doctor, pharmacist, and other healthcare providers about any dietary supplements and medicines you take. They can tell you if those dietary supplements might interact or interfere with your prescription or over-the-counter medicines or if the medicines might interfere with how your body absorbs, uses, or breaks down nutrients. Foods contain vitamins, minerals, dietary fiber and other components that benefit health.
In some cases, fortified foods and dietary supplements are useful when it is not possible to meet needs for one or more nutrients e. For more information about building a healthy dietary pattern, see the Dietary Guidelines for Americans and the U.
Department of Agriculture's MyPlate. This fact sheet by the Office of Dietary Supplements ODS provides information that should not take the place of medical advice. We encourage you to talk to your healthcare providers doctor, registered dietitian, pharmacist, etc. Any mention in this publication of a specific product or service, or recommendation from an organization or professional society, does not represent an endorsement by ODS of that product, service, or expert advice.
Rat studies examining the importance of vitamin A in male reproduction have shown that a deficiency blocks the development of sperm cells, causing infertility 33 , Likewise, animal studies have suggested that vitamin A deficiency in females can impact reproduction by reducing egg quality and affecting egg implantation in the womb In pregnant women, vitamin A is also involved in the growth and development of many major organs and structures of the unborn child, including the skeleton, nervous system, heart, kidneys, eyes, lungs and pancreas.
Yet, though much less common than vitamin A deficiency, too much vitamin A during pregnancy can be harmful to the growing baby as well and may lead to birth defects 35 , Adequate amounts of vitamin A in the diet are essential for reproductive health and the healthy development of babies during pregnancy.
Vitamin A is a fat-soluble vitamin , which is stored in your body. This means that excess consumption can lead to toxic levels. Hypervitaminosis A is caused by consuming too much preformed vitamin A through your diet or supplements containing the vitamin.
Though it can be caused by excessive intake from the diet, this is rare compared to overconsumption from supplements and medications. Eating high amounts of the active form of vitamin A from animal foods, medications or supplements can be toxic. Excessive consumption of provitamin A from plant foods is unlikely. The best way to ensure you get the balance right is to consume vitamin-A-rich foods as part of your normal diet and avoid supplementing with excessive amounts.
Hypervitaminosis A, or vitamin A toxicity, occurs when you have too much vitamin A in your body. This condition may be acute or chronic. This article lists 20 foods that are high in vitamin A. This is a fat-soluble vitamin that plays an essential role in eye and immune health. While vitamin A deficiency is rare in developed countries, certain people may be at a higher risk.
Here are 8 signs and symptoms of vitamin A…. Learn about vitamin A palmitate, how it compares to vitamin A, and its potential health benefits. Taking care of your skin should be an essential part of your health regimen. Learn about vitamins D, C, E,.
There are four fat-soluble vitamins in the human diet: A, D, E and K. This guide examines their health benefits, functions and main dietary sources. Prenatal nutrition can be confusing. This article explains which supplements are believed to be safe during pregnancy and which ones you should avoid. Acne surfaces during times of hormonal imbalance.
Some seek natural treatments such oral vitamin and mineral supplements. Learn which natural remedies…. The foods you eat play a big role in your overall health. Vitamin D has numerous health benefits, but it's tricky to know which supplement to choose.
If you take a supplement that contains vitamin A, do not take too much because this could be harmful. Liver is a very rich source of vitamin A. Women who have been through the menopause and older men, who are more at risk of osteoporosis, should avoid having more than 1.
Having an average of 1. Page last reviewed: 03 August Next review due: 03 August Vitamin A, also known as retinol, has several important functions. The main food sources of beta-carotene are: yellow, red and green leafy vegetables, such as spinach, carrots, sweet potatoes and red peppers yellow fruit, such as mango, papaya and apricots How much vitamin A do I need?
What happens if I take too much vitamin A?
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