Gamma-tocopherol as a possible marker for nutrition-related risk: results from four national diet and nutrition surveys in britain.
Sommaire de l'article
Relationships between vitamin E status (alpha and gamma-tocopherol and their ratio in plasma), anthropometric and biochemical indices, and food and nutrient intakes, were studied in four British National Diet and Nutrition Surveys: children aged 1.5-4.5 years, young people aged 4.0-18.0 years, adults 19.0-64.0 years and adults aged > or = 65.0 years. gamma-Tocopherol:alpha-tocopherol ratio declined with age. In older women gamma-tocopherol and gamma-tocopherol:alpha-tocopherol ratios were directly related to indices of obesity. In young men alpha- and gamma-tocopherols were directly correlated with obesity, but gamma-tocopherol:alpha-tocopherol ratio was not. For young people and toddlers, fewer obesity indices were available and relationships were weaker. Other fat- and water-soluble vitamin indices correlated directly with alpha-tocopherol and inversely with gamma-tocopherol and gamma-tocopherol:alpha-tocopherol ratio. Whereas alpha-tocopherol correlated directly with ‘healthy’ nutrient choices (such as intrinsic sugars, dietary fibre, vitamins and potassium) and inversely with ‘unhealthy’ choices (extrinsic sugars and monounsaturated fats, i.e. avoidance of polyunsaturated fat), gamma-tocopherol and the gamma-tocopherol:alpha-tocopherol ratio related inversely with ‘healthy’ choices. Food groups had analogous relationships; thus, alpha-tocopherol related directly to use of polyunsaturated fats, fresh fruits and fruit juices, and inversely to non-polyunsaturated fats and extrinsic sugar. The reverse was true for gamma-tocopherol and gamma-tocopherol:alpha-tocopherol ratio. Although the mechanisms underlying these relationships are obscure, the gamma-tocopherol:alpha-tocopherol ratio may reveal poor dietary choices, status predictors and a propensity for obesity in later life, especially in women.