M. Vandewoude

Vitamin E status in patients on parenteral nutrition receiving intralipid

Low vitamin E levels have been found to be a frequent side effect in patients on total parenteral nutrition (TPN). In the present study, the vitamin E content of fat emulsions (Intralipid) was measured and the influence of the intravenously administered lipid emulsion on plasma vitamin E levels was investigated. The majority of vitamin E was provided in the beta + gamma-tocopherol fractions (68.7% of total tocopherol). Vitamin E levels in patients were significantly lower (p less than 0.05) as compared to age- and sex-matched normal controls. Although sufficient amounts of vitamin E (16.9 +/- 0.8 IU daily) were infused, according to RDA requirements, E-plasma levels decreased even further during the course of TPN. It was concluded that high amounts of biologically less active tocopherol isomers are not sufficient to maintain vitamin E plasma levels. Supplemental sources of alpha-tocopherol are needed and more attention should be paid to the different tocopherol isomers in the quantitation of the daily allowances of vitamin E.

Vitamin E status in normocholesterolemic and hypercholesterolemic diabetic patients

SummaryThe close relationship between vitamin E, lipid and prostaglandin metabolism stresses the need for an accurate definition of the status of vitamin E in a diabetic population. Plasma vitamin E and plasma lipids were determined in 34 type I and 21 type II normocholesterolemic and in 7 hypercholesterolemic diabetics. They were also measured in 62 age-and sex-matched controls, 34 normocholesterolemic controls for type I, 21 normocholesterolemic controls for type II and 7 hypercholesterolemic individuals. Plasma vitamin E levels were not significantly different in type I and type II diabetics as compared to their respective control groups. Vitamin E levels were significantly increased (p<0.001) in hypercholesterolemic individuals, both in diabetics and in non-diabetics. The vitamin E/cholesterol ratio in these subjects was, however, not different from that of normocholesterolemic. Plasma vitamin E was correlated with plasma lipids, especially with total and LDL-cholesterol (p<0.001). Since vitamin E is mainly transported by plasma lipoproteins, these strong correlations suggest that changes in plasma vitamin E should be considered as an epiphenomenon of altered plasma transport capacity.

Evaluation of magnesium before and after jejuno-ileal versus gastric bypass surgery for morbid obesity.

Jejuno-ileal bypass surgery for morbid obesity can cause metabolic and electrolyte imbalances. Another case of severe, symptomatic magnesium deficiency after jejuno-ileal bypass surgery is described. This complication was not encountered in a prospective evaluation of the magnesium status after gastric restrictive bypass surgery. Significant (p less than 0.005) body weight decrease was not accompanied by any (serum, erythrocyte or urinary) evidence of magnesium loss for 12 months after surgery.

Changes in Vitamin E Status during Obesity Treatment

The effects of vitamin E on platelet function and erythrocyte membrane rigidity are extensively described. Little is known, however, about the vitamin E status in an obese population and about the effect of weight loss on it. This study evaluates the changes in vitamin E status during obesity treatment in 8 morbidly obese females. They received a protein-sparing modified fast (PSMF) diet for a period of 5 weeks; mean vitamin E supplementation did not exceed the recommended daily allowance (8 mg of alpha-tocopherol equivalents). During the investigated period plasma vitamin E levels increased (p less than 0.02), while there was a slight decrease in plasma cholesterol. The rise in total tocopherol/total cholesterol ratio was highly significant (p less than 0.002). Both the experimental design and the results are comparable with previously reported data in hypothalamic obese mice. It is, therefore, suggested that the hypothalamic obese mouse is a convenient animal model for the study of vitamin E nutritional status in obesity.

Influence of intravenous hyperalimentation on cardiac dimensions and heart function

Eleven severe malnourished patients, mean age 34 yrs and mean weight 66 per cent of ideal body weight, were studied to evaluate the effect of intravenous hyperalimentation on the function and size of the heart. Left ventricular size and systolic function were measured before and after a mean weight gain of 19 per cent with electro, vector, echo and phonomechanographic methods. During hyperalimentation a statistically significant increase in left ventricular mass (p<0.01) was observed. Correction for body weight showed a parallel increase between the parameters and weight gain. Echocardiographic and phonomechanographic indexes of left ventricular systolic function remained unchanged. A decrease of the amplitude of the maximal spatial QRS vector was shown by vectocardiography. These results indicate that during intravenous hyperalimentation of the severe malnourished a proportional increase in cardiac size and mass occurs with preservation of the left ventricular systolic function.