High Dietary Fat and Cholesterol Exacerbates Chronic Vitamin C Deficiency in Guinea Pigs

Br J Nutr. 2011 Jan;105(1):54-61. doi: 10.1017/S0007114510003077. Epub 2010 Sep 28.

Abstract

Vitamin C deficiency - or hypovitaminosis C defined as a plasma concentration below 23 μm - is estimated to affect hundreds of millions of people in the Western world, in particular subpopulations of low socio-economic status that tend to eat diets of poor nutritional value. Recent studies by us have shown that vitamin C deficiency may result in impaired brain development. Thus, the aim of the present study was to investigate if a poor diet high in fat and cholesterol affects the vitamin C status of guinea pigs kept on either sufficient or deficient levels of dietary ascorbate (Asc) for up to 6 months with particular emphasis on the brain. The present results show that a high-fat and cholesterol diet significantly decreased the vitamin C concentrations in the brain, irrespective of the vitamin C status of the animal (P < 0·001). The brain Asc oxidation ratio only depended on vitamin C status (P < 0·0001) and not on the dietary lipid content. In plasma, the levels of Asc significantly decreased when vitamin C in the diet was low or when the fat/cholesterol content was high (P < 0·0001 for both). The Asc oxidation ratio increased both with low vitamin C and with high fat and cholesterol content (P < 0·0001 for both). We show here for the first time that vitamin C homoeostasis of brain is affected by a diet rich in fat and cholesterol. The present findings suggest that this type of diet increases the turnover of Asc; hence, individuals consuming high-lipid diets may be at increased risk of vitamin C deficiency.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antioxidants / administration & dosage
  • Antioxidants / metabolism*
  • Ascorbic Acid / administration & dosage
  • Ascorbic Acid / blood
  • Ascorbic Acid / metabolism*
  • Ascorbic Acid Deficiency / blood
  • Ascorbic Acid Deficiency / metabolism*
  • Brain / drug effects*
  • Brain / metabolism
  • Cholesterol, Dietary / adverse effects*
  • Cholesterol, Dietary / blood
  • Chronic Disease
  • Dietary Fats / adverse effects*
  • Dietary Fats / blood
  • Disease Models, Animal
  • Guinea Pigs
  • Homeostasis
  • Oxidation-Reduction
  • Oxidative Stress / drug effects*

Substances

  • Antioxidants
  • Cholesterol, Dietary
  • Dietary Fats
  • Ascorbic Acid