Day 036 - 13 Oct 94 - Page 07
1 cancers in women are attributable to diet". I can tell
2 you that reference 46 there is the work of Doll and Peto
3 in 1981 as it so frequently is given for that estimate, is
4 it not?
5 A. Yes.
6
7 Q. "The evidence for the influence of diet on cancer is
8 derived from several sources. Correlations between
9 national and regional food consumption data and cancer
10 rates and studies of the changing rates of cancer in
11 populations as they migrate from a region or country of
12 one dietary culture to another have led to many important
13 hypotheses" -- I ask you to note the word "hypotheses" --
14 "case-control studies of the dietary habits of cancer
15 patients in comparison subjects and prospective studies of
16 populations with known dietary habits provide stronger
17 evidence for the effects of diet in relation to major
18 cancers". Pausing there, do you agree or disagree with
19 that sentence in this report?
20 A. The only change that I would make is, before the word
21 "provide", I might add the word "may" because in some
22 cases case-control studies and prospective studies do not
23 provide additional evidence and in some cases they do.
24
25 Q. I am going to come later on today to one of the supposed
26 defects in cohort studies, but we will leave that for the
27 moment. It goes on: "Many of these observations for
28 human populations have been supported by animal
29 experimental data. Studies of diet in relation to some
30 cancers have been confined to relatively homogeneous
31 populations and have not been replicated across a range of
32 cultural and dietary settings. For other cancers the
33 research has been pursued over a wider range of dietary
34 intakes. Included among the cancers that have been linked
35 repeatedly to dietary factors and in different populations
36 cancers of the oral cavity, pharynx, larynx, oesophagus,
37 stomach, large bowel, liver, pancreas, lung, breast,
38 endometrium and prostate". Is there anything in that
39 paragraph with which you would disagree?
40 A. No.
41
42 Q. No. I would like you to turn, please, to page 91 where
43 elements in the diet are considered. The first one which
44 was considered was dietary energy on page 89. I do not
45 require any reference to that, but I would like you to
46 look at paragraph headed 4.1.2. Fat Consumption on page
47 91. May I read it to you?
48 A. Please.
49
50 Q. "As the total fat content of the diet increases, an
51 increasing proportion of persons within the population,
52 including particularly the most susceptible individuals
53 within that population". Pausing there, Dr. Barnard, do
54 you agree that (this is dealing with obesity), so far as
55 obesity is concerned, there are individuals within
56 societies who are more naturally susceptible to obesity
57 than others?
58 A. Well, everyone has the potential to gain substantial
59 amounts of weight. Certain people are particularly
60 susceptible to that; yes, correct.
