Effects of elevated d-alpha(RRR)-tocopherol dosage in man

Area of Science:

• Nutritional Science
• Biochemistry
• Human Physiology

Background:

• Vitamin E, particularly alpha-tocopherol, is a crucial lipid-soluble antioxidant.
• Investigating the effects of high-dose supplementation is important for understanding its physiological impact and safety.

Purpose of the Study:

• To assess the impact of megadosage RRR-alpha-tocopherol on alpha-tocopherol levels in various blood and cellular components.
• To evaluate the safety and tolerability of high-dose RRR-alpha-tocopherol supplementation.
• To observe the effects on gamma-tocopherol levels.

Main Methods:

• A single-blind study involving 19 healthy college students.
• 14 participants received 600 mg (900 IU) of RRR-alpha-tocopherol daily for 12 weeks; 5 received a placebo.
• Measurements included alpha-tocopherol in plasma, RBCs, platelets, WBCs, and buccal cells, alongside safety markers (thyroid, liver, kidney function, coagulation, immunoglobulins).

Main Results:

• Alpha-tocopherol levels in plasma, RBCs, and WBCs peaked at 4 weeks and plateaued; platelet and buccal cell levels peaked at 12 weeks.
• Maximum levels were 2.5-3 times baseline values.
• No significant changes were observed in safety markers, and participants remained healthy without adverse symptoms. Gamma-tocopherol levels were suppressed in plasma and RBCs.

Conclusions:

• Megadosage RRR-alpha-tocopherol is well-tolerated in healthy young adults.
• Supplementation effectively increases alpha-tocopherol concentrations in various tissues.
• High-dose alpha-tocopherol may suppress gamma-tocopherol levels, indicating potential metabolic interactions.