Dietitians discount health risk in aluminium we absorb

Press, 7 August 1985, Page 13

Dietitians discount health risk in aluminium we absorb

Two Christchurch dietitians, Mrs Julian Jensen, the chairman of the local branch of the Dietetic Association, and Mrs Pamela Williams, the chief dietitian with the Canterbury Hospital Board, believe those who read the article on aluminium by Dr Lois Tucker need not throw away their aluminium, saucepans and teapots just yet. While they do not refute Dr Tucker’s article, they maintain that the whole picture on the alleged dangers of aluminium was not given. “Dr Lois Tucker threw some doubt on to the safe use of aluminium utensils in the home and the possible

ill effects such use can have on health,” they say. “A more recent review than the University of Cincinatti studies of dietary aluminium and its connection to Alzheimer’s disease was published in ‘The Science of the Total Environment,’ 1981 (17:31). “We do not believe that on the present scientific evidence, there is any necessity for the public to dispose of their aluminium saucepans and teapots, in order to protect their health. “Aluminium is the most common metallic element in the earth’s crust, and life on this planet has developed in a medium that was surrounded with aluminium silicate clays.

“These silicates are extremely insoluble in normal conditions, as are the phosphate and fluoride salts. Consequently, they all have low nutritional availability in this form. “At the beginning of this century, a neuro-pathologist, Alois Alzheimer, studied dementia in old age. He described the changes that took place in the brain of some older persons and was able, because of new staining techniques, to describe the cell changes characteristic of an irreversible dementia which is now. known by his name. “This disease usually appears after the age of 45. There is a progression of changes, starting with impaired memory and a deterioration of intellect and personality. “There is suggestion of some genetic predisposition to Alzheimer’s disease, but no definite scientific evidence that nutrition is involved in this condition. “We do not believe at this stage that there is a basis for associating Alzheimer’s disease, or dementia, with the ingestion of aluminium compounds. Alzheimer did his work at- least 20 years before aluminium saucepans became popular, or before aluminium compounds were used for clinical purposes, as they are now, in antacids.

“There are only trace amounts of aluminium in the normal diet, and it has no known function in humans. Also, it is very poorly absorbed from the gastro-intestinal tract, through the lungs, or the skin. “Most diets average about 22 mg of aluminium a day, of which less than 1 mg is absorbed. The effect of any increase in the aluminium content of foods, or the diet, would be unlikely to be significant. “Medicines, such as antacids which are high in aluminium, can be substituted with equally effective alum-inium-free ones. “In a recent study (1979) reported in ‘Neurology,’ McDermott et al. reported on a study of brain tissue in the ageing population. The study compared a control group who showed no neurological symptoms with those with Alzheimer’s disease. “Although brain aluminium increases with age, there were no statistically significant differences in the aluminium concentration of patients with Alzheimer’s disease, and the control patients. “There is need for caution for patients with chronic renal disease, and patients on total parenteral nutrition. Both may be susceptible to the effects of an

accumulation of aluminium because of clinical treatment required. “However, precautions can be taken to ensure that the effects of excess aluminium are minimised. “The discussion concerning aluminium and neurological damage is probably far from over. The subject may be discussed indefinitely until the need is recognised for careful experimental controls on all work reported. “Without proper controls for comparison, it is easy to confuse kidney damage effects with ‘aluminium toxicity’.” The acid base balance is very important in determining the absorption rate of aluminium. In the past, results have often confused aluminium toxicity with the varying effects of pH. “To date it has not been established whether or not aluminium is a required element in the diet and if so, what is the daily requirement. “While high levels of aluminium resulting from abnormal pathological conditions may be associated with neurological disorders, it is unlikely that the use of aluminium cookware has any significant consequence in the development of mental disorders,” they say.