Vitamin E or tocopherol is a fat-soluble vitamin that functions as an antioxidant and is important for its role in anti-inflammatory processes, its inhibition of platelet aggregation and its immune-enhancing activity.
Vitamin E levels
The term vitamin E encompasses 8 compounds, four tocopherols and 4 tocotrienols, which occur naturally in foods of plant origin. Tocopherol is the main and most abundant form of vitamin E and can be alpha-tocopherol, beta-tocopherol, gamma-tocopherol and delta-tocopherol.
Humans are not able to synthesize vitamin E, so it is necessary to access it through food, by consuming foods from plant sources, since vitamin E is formed from photosynthetic processes in plants.
Vitamin E is insoluble in water. On the contrary, it is fat-soluble, like vitamins A, D and K. For this reason, the absorption of vitamin E depends on the absorption of lipids in the intestine, requiring pancreatic and biliary secretions. Once bound to the epithelial cells of the intestine, vitamin E is incorporated into chylomicrons, being secreted into the systemic circulation.
Vitamin E is essential for the prevention of oxidative stress by inhibiting the production of reactive oxygen species when fats are oxidized. It also protects the cell membrane and is necessary to maintain proper skeletal muscle homeostasis.
Vitamin E deficiency due to low dietary intake is rare in developed countries. Vitamin E deficiency is usually secondary to disorders that hinder the absorption of vitamin E from fats, such as liver disorders, disorders of fat metabolism and disorders of biliary secretion.
Among the most common causes of vitamin E deficiency are impaired absorption of fatty acids involved in vitamin E metabolism, mutations in the tocopherol transfer protein, patients with cystic fibrosis (a lung disorder that can also affect bile secretion), patients with cystic fibrosis (a lung disorder that can also affect biliary secretion), patients with a history of biliary secretion, and patients with a history of bile secretion.These include patients with cystic fibrosis (a lung disorder that can also affect biliary secretion), patients with intestinal and/or liver syndromes or diseases such as cholestasis or primary biliary cirrhosis, and those with certain inherited monogenic diseases directly or indirectly related to vitamin E, such as abetalipoproteinemia (a digestive disorder characterized by malabsorption of fats).
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