METABOLISM OF VITAMIN E HENDRA WIJAYA Esa Unggul University Okt 2012

Chemical form of vitamin E

Vitamin E in Food

Benefits of Vitamin E

11 Absorption and Transport Dependent on ability to absorb fat Absorbed into lymphatic system Component of chylomicrons Alpha-tocopherol is major tocopherol in plasma Positive association between serum lipid and tocopherol levels Normal range is mg/dl

Absorption and Transport The ability of an individual to absorb vitamin E is dependent on the ability to absorb fat. Vitamin E is absorbed into the lymphatic system from the intestines and enters the blood as a component of the chylomicrons. The majority of vitamin E in plasma is in the low-density lipoproteins. Alpha-tocopherol is the major tocopherol in adult plasma and accounts for approximately 87% of the total tocopherol concentration. There is a positive association between serum lipid levels and tocopherol levels. Vitamin concentrations in body tissues vary considerably. Adipose tissue and adrenal glands have the highest levels. Vitamin E levels in plasma range from mg/dl in normal populations. In general, a 10-fold increase in vitamin E intake will double plasma concentrations.

Co-Work Vit C With Vit E

Human requirement For the 19- to 50-year age group, an EAR of 12 mg of α-tocopherol is derived from studies in men based on the criterion of vitamin E intakes suffi cient to prevent hydrogen peroxide-induced haemolysis. The RDA is 120% of the EAR which, after rounding up, is 15 mg per day of α- tocopherol. There is no increase for pregnancy, but for lactation the RDA is increased to 19 mg per day

Toxicity Vitamin E is regarded to be non-toxic. There is no evidence of adverse effects from the consumption of vitamin E naturally occurring in foods. The question of toxicity arises when vitamin E is used in pharmacological amounts for ‘therapeutic’ purposes. Animal studies have shown that α-tocopherol is not mutagenic, carcinogenic or teratogenic. In human studies with double-blind protocols and in large population studies, oral vitamin E supplementation resulted in few side effects even at doses as high as 3200 IU per day