Milk and coronary heart disease mortality.

Milk and coronary heart disease mortality The self completed questionnaire study by Ness et al 1 found that men who reported drinking more than a third of a pint of milk each day were not at increased risk of death from coronary heart disease (CHD) in comparison with those drinking less than this or none. The study inappropriately equates daily milk consumption with the answers the participants gave to the single question that asked how many pints of milk the men usually drank each day. This was in 1970 or 1973, when in Britain milk was normally delivered to households in pint bottles. The meaning of the question lacks precision, and may have caused some of the participants to exclude milk taken out of the home in hot beverages and in milk drinks such as milk shakes. The authors note that the question did not ask about milk used in food preparation, so some answers could have excluded regular milk intake in porridge, with cereals, and as milk puddings or custard. Milk in milk chocolate and milk or constituents in ready made foods would certainly have been excluded. It is feasible that some participants who drank less than a third of a pint of milk as such consumed more milk from these other sources than did those who reported drinking more than this amount. Five years, on average, after the initial screening, about half of the participants returned for a second screening, which apparently showed " a reasonable level of stability in reported milk consumption. " This does not necessarily translate into the same relation with CHD mortality of the reported milk drinking of the whole cohort at the initial screening and of the half at the second screening. The latter results should therefore have been included in the published paper. The follow up period took place against a background of falling milk consumption 2 and CHD mortality 3 in the United Kingdom. The significance of relating levels of milk intake in 1970 and 1973 to CHD mortality up to 25 years later is therefore questionable, especially as lifestyle changes that include restriction of milk to one cup daily can bring about regression of coronary atherosclerosis in one year. 4 In the discussion, Ness et al state that the Caerphilly cohort study showed a striking inverse association between milk consumption and CHD risk, but they fail to refer to the …