Day 017 - 25 Jul 94 - Page 32
1
Q. "It may be asked whether the geographic correlation with
2 total fat can be partly due to the effects of excess
calories when caloric intakes themselves give appreciably
3 lower correlations with breast cancer (r= 0.57 with
incidence, 0.71 with mortality). However, crude estimates
4 of caloric intake of a whole population are far from being
equivalent to the excess", that word in italics, "calories
5 consumed by its women. Food balance tables make no
adjustment for caloric expenditure in physical work -
6 obviously much greater in the less developed countries.
Indeed, if an adjustment is made for the proportions of
7 the populations of different countries engaged in heavy
physical work, and also for their body build, higher
8 correlation coefficients between excess calories and
breast cancer incidence can be found that approximate to
9 those found with fat (Kinlen, Balkwill and West in
preparation).
10
At the population level the international data do not
11 allow fat to be distinguished adequately from other
features of wealth, while at the individual level we are
12 ignorant of whether the effects of calories from fat
differ from (calories) carbohydrate and protein. Until
13 such a difference is found, it seems preferable to regard
excess calories from any source as the important
14 factor." That is in 1987. Dr. Arnott, have we advanced
beyond that proposition?
15 A. I do not think so because, in fact, it is a very
reasonable proposition which was made and the state of our
16 knowledge has, sadly, not progressed since that time.
17 Q. This paper by Dr. Kinlen tends to -- I will not say acquit
certainly shrinks from implicating fat as a prime factor,
18 fat alone; more of suspicion is cast on total calorie
intake and protein. How far would you go in stigmatizing
19 total calorie intake now as a cause of cancer in women,
breast cancer?
20 A. I would actually have to say that we do not know the
answer to that question. There does seem to be a
21 correlation with people being overweight and certainly
mortality in breast cancer and in other cancers. But,
22 exactly the way in which this is mediated, I do not think
we know the answer.
23
And I think what Dr. Kinlen is saying in this article is
24 this very point that, you know: "Look, there has been all
this evidence so far which has suggested that there may be
25 a relationship between fat and cancer, but we do not know
that, and there is good contrary evidence to suggest that
26 it is not fat that is the prime suspect, and it may be
that it is just over nutrition in a general sense".
27
Q. Can you pass on -- I am not going to read any more at the
28 moment of this text except the conclusion -- there is a
passage about obesity and mortality, then there is a
29 passage about the Japanese, then a passage about the
effect of reduction or not in fat consumption in adult
30 life, including some work done by Dr. Kinlen himself which
has been mentioned earlier, then a passage about animal
