The nutrients which may be lacking in a crash diet are protein, the vitamins folacin, thiamin
(vitamin B-1), riboflavin (vitamin B-2) and pyridoxine (vitamin B-6), the minerals potassium,
magnesium and zinc, and dietary fibre.
It is possible to increase the nutritional quality of low energy diets by including nutrient-rich foods
like liver, wheat germ and yeast.
Energy intakes lower than 3400 kilojoules (800 kilocalories) per day must be accompanied by
nutrient supplements or be provided by formula feeds, under medical supervision.