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Nutritional Diseases
Published in Ayşe Serap Karadağ, Lawrence Charles Parish, Jordan V. Wang, Roxburgh's Common Skin Diseases, 2022
Chelsea Kesty, Madeline Hooper, Erin McClure, Emily Chea, Cynthia Bartus
Hypervitaminosis A can be deadly. It is important to correct toxic over-supplementation and monitor systemic retinoid patients. The incurred liver damage may be irreversible, and women of childbearing potential may risk fetal defects.
Micronutrients
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
Since vitamin A is fat-soluble, it can be stored longtime in the body, primarily in the liver. Routine intake of large amounts of vitamin A supplements or polar bear liver over a period of time can result in toxic symptoms, including liver damage, bone fractures, joint pain, increased intracranial pressure, dizziness, alopecia (hair loss), headaches, vomiting, blurry vision, insomnia, fatigue, weight loss, drying of the mucous membranes, skin desquamation, coma, and even death (3, 9, 33, 56–58). Children are more sensitive than adults to a high retinol intake. These toxicities only occur with preformed vitamin A (retinoid), but not with carotenoids such as β-carotene. Hypervitaminosis A is usually a result of consuming too much preformed vitamin A from supplements or therapeutic retinoids (56). High intakes of preformed vitamin A supplement (more than 1,500 µg/day, only slightly higher than the RDA) can reduce bone mineral density, and increase fracture risk (56). In addition, there is also evidence that retinol is teratogenic (causing developmental malformation of the fetus and birth defect). Consequently, it has been suggested that pregnant women or those who are trying to become pregnant should not take vitamin A supplements and should not eat liver or liver products in high amounts (9, 33). Nevertheless, pregnant women are advised not to consume more than 3,000 µg/day (10,000 IU) vitamin A supplement to avoid risk of fetal toxicity (3, 33, 56). Consult a doctor before using vitamin A supplement if you are pregnant.
Exercise and pregnancy
Published in Hung N. Winn, Frank A. Chervenak, Roberto Romero, Clinical Maternal-Fetal Medicine Online, 2021
Many active women will begin pregnancy underweight. Among these women, there is an increased awareness of body image, and many of them will continue to consume inadequate low-calorie diets during their pregnancies. To compensate for these low-calorie diets, they will frequently turn to excessive use of vitamins. Excessive intake of vitamins can result in an increased incidence of congenital malformations. Excessive ingestion of vitamin D could result in a neonatal syndrome consisting of supravalvular aortic stenosis, elfin facies, and mental retardation (35). Hypervitaminosis A may cause urogenital anomalies, ear malformations, cleft palate, and neural tube defects (36). The iron status should be assessed since many of these women may have preexisting depleted iron stores.
Efficacy of B-vitamins and vitamin D therapy in improving depressive and anxiety disorders: a systematic review of randomized controlled trials
Published in Nutritional Neuroscience, 2023
Jaqueline G. Borges-Vieira, Camila K. Souza Cardoso
When it comes to vitamin D, it is critical to be aware that overdose can be toxic. Excessive supplementation for too long can inhibit parathyroid hormone (PTH), culminating in increased calcium absorption from the gastrointestinal tract and hypercalcemia. This condition can cause adverse effects such as nausea, vomiting, muscle asthenia, joint pains, polyuria, dehydration [116]. Due to hypervitaminosis D, the increased risk of tissue calcification, especially of coronary vessels and heart valves, is investigated, but current findings remain controversial [117]. The current DRI [83] is 600 IU/day for 19–70 years, or 800 IU/day for 71 years and older, with the UL considered safe for an intake of 4,000 IU/day for men and women — although higher doses with individualized frequency can be performed in clinical practice under supervision [118]. Lastly, consider that Vitamin D supplementation should be based on the personal vitamin D response as some genetic variations (like the MTHFR gene on vitamins B) may also influence vitamin D metabolization and, thereby, the response to supplementation and the vitamin D status based on 25(OH)D3 serum measurements [119,120].
Pseudotumor Cerebri Syndrome with Resolution After Discontinuing High Vitamin A Containing Dietary Supplement: Case Report and Review
Published in Neuro-Ophthalmology, 2018
Jason T. Chisholm, Michelle M. Abou-Jaoude, Amy B. Hessler, Padmaja Sudhakar
One of the most well-established secondary causes of PTCS is hypervitaminosis A, and there is good evidence that this syndrome can be induced if enough vitamin A is ingested.6,19 Studies have found serum vitamin A levels, in the form of retinol, to be significantly higher in idiopathic PTCS patients,20,21 and others have found significantly higher retinol levels in the cerebrospinal fluid as well.21–23 In 2007, Warner et al. found that the ratio of retinol to retinol binding protein (RBP) in the CSF was higher in patients with PTCS and was >1.0, suggesting the presence of unbound retinol, which they theorized may be toxic to arachnoid villi and lead to impaired CSF resorption.21 Increased RBP in the serum of individuals with PTCS has been reported in two studies, suggesting that the unbound toxic retinol in the CSF may be due to insufficient RBP transfer into the CSF compartment.21,24
When and How to Diagnose and Treat Vitamin D Deficiency in Adults: A Practical and Clinical Update
Published in Journal of Dietary Supplements, 2020
Antoine Aoun, Jessica Maalouf, Myriam Fahed, Flora El Jabbour
Vitamin D toxicity should not be diagnosed solely on the basis of an elevated 25(OH)D level; it should rather be recognized as a clinical syndrome of both hypervitaminosis D and hypercalcemia, in which hyperphosphatemia and hypercalciuria also commonly occur. Patients with vitamin D toxicity can present with clinical symptoms (e.g., headache, metallic taste, nausea, and vomiting) and complications of hypercalcemia (e.g., dehydration, constipation, pancreatitis, and heart arrhythmias) and hypercalciuria (e.g., polyuria and kidney stones) (National Institute of Health 2016). While hypervitaminosis D in the absence of hypercalcemia may prompt further investigation to evaluate the etiology of increased vitamin D levels, it is not a medical emergency as is hypercalcemia.