Evidence points to A1 link to diabetes

By Deborah Hill Cone

Friday 1st November 2002

Diabetes specialist Professor Bob Elliott became interested in the increased incidence of diabetes among Western Samoan children who came to live in New Zealand. A significant difference in their diet was that in New Zealand they drank more cow's milk. He also noticed that although Masai children in Kenya had a high milk consumption, the incidence of diabetes was low. Masai cattle produce milk with predominantly beta casein (milk protein) A2. His research suggested that rather than all milk being linked with Type 1 diabetes it was possible there was a link only with the A1 milk protein.

Funded by the Dairy Board and Child Health Research Foundation.

Food and Diabetes Trial, published 2002 Diabetologica

Beta casein A1 and beta casein A2 was fed to diabetes-prone rats and mice in Auckland, Canada and the UK. In Canada, rats fed beta casein A1 developed a significantly higher rate of Type 1 diabetes than those fed with beta casein A2. The trial failed in Auckland as the animals died. In the UK there was no clear outcome.

Funded by the Dairy Board.

The Elliott study, published 1999 in Diabetologia

Further study by Professor Elliott in which beta casein A1 and beta casein A2 was fed to non-obese diabetic-prone mice. The mice fed beta casein A1 developed high levels of Type 1 diabetes whereas those fed beta casein A2 did not.

Funded by the Dairy Board.

The McLachlan study, published early 2001 in Medical Hypotheses

Scientist Corran McLachlan (now chief executive, A2 Corporation) found an unusually strong correlation between the consumption of A1-type milk and deaths from coronary heart disease. The study was based on data from 19 countries.

Funded by Dr McLachlan with support from family and colleagues.

Japanese study, published 1999 in Peptides

Professors Yundes Jinsmaa and Masaaki Yoshikawa at Kyoto University found BCM-7 was only released from the milk protein, known as A1, but scientifically described as the beta casein that "contained His residue at the 67th position on the peptide chain."

Funded by Kyoto University Research Institute for Food Science.

Finnish study, published 2000 in Diabetes

Finland has one of the highest rates of Type 1 diabetes in the world. In this study by the Childhood Diabetes in Finland Study Group, 173 newborns who had a relative with Type 1 diabetes were tracked to eight months. Half were given milk formula, the other half a formula already broken down to peptides. Ten out of 89 of the cow's milk children developed antibodies associated with type 1 diabetes, compared to three out of 84 of the treated formula children. The study did not differentiate between A1 milk and A2 milk.

Funded by the Childhood Diabetes in Finland Study Group.

German study

Similar to the Japanese study but not so widely available, it found beta-casomorphin-7 (BCM-7) could be released only from A1 variants and not A2 type variants.

Funding information not available.

US Study, published 1999 in Autism

This study by Professor Robert Cade (incidentally the inventor of the sports drink Gatorade) at the University of Florida at Gainsville found BCM-7 binds to brain cells via morphine receptor sites on brain cells. When BCM-7 was injected into rats they had marked behavioural changes akin to schizophrenia.

Funded by the University of Florida.

First Icelandic study, published 2000 in Pediatrics

In Iceland the incidence of diabetes is half that of other Nordic countries. This study showed the percentage of beta casein A1 and B variants in Icelandic milk was significantly lower than in the milk from other Scandinavian countries. It concluded a lower percentage of A1 in Icelandic cows milk may explain why there is a lower incidence of Type 1 diabetes.

Funded by the Icelandic Research Council and Foundation of Research Science and Technology.

Second Icelandic study

Published 2002 as a dissertation "The influence of nutrition on prevention of diabetes mellitus cow's milk and Type 1 diabetes."

Lower amounts of A1 and B beta casein found in Icelandic cow's milk, resulting in lower consumption of the proteins by young children, may explain lower incidence of Type 1 diabetes in Iceland.

Funded by the Icelandic Research Council and FoRST NZ.

Queensland study, submitted for publication in Atherosclerosis

Professor Julie Campbell at the University of Queensland Centre for Research in Vascular Biology found the consumption of A1 milk increases the risk of heart disease in rabbits, while the consumption of A2 milk does not.

Funded by A2 Corporation.

Comments from our readers

No comments yet