Day 033 - 10 Oct 94 - Page 52
1 sex hormone that is responsible for sexual development.
2 The liver pulls, or one of the means by which the body
3 deals with them, is that the liver pulls the oestrogens
4 out of the blood, sends them down the bile duct into the
5 intestinal tract. If the diet contains substantial
6 amounts of fibre, those oestrogens are carried out with
7 the waste. If the diet is devoid of fibre, relatively
8 speaking, those oestrogens can be reabsorbed through the
9 bowel wall and go back into the blood -- recycling, if you
10 will, of hormones.
11
12 The same thing is believed to occur in men with the
13 hormone testosterone. This recycling of hormones is
14 believed to be the reason why high fibre diets -- well,
15 high fibre diets help to rid the body of excess oestrogen;
16 fibre depleted diets increase oestrogen levels. Likewise
17 high fat diets increase oestrogen levels.
18
19 The National Cancer Institute quoting a study by,
20 I believe, Prentice says that if the dietary fat intake is
21 reduced to 20 per cent of calories, oestrogen levels will
22 drop by about 17 per cent. These things all influence the
23 sexual development of young girls, and if the age of
24 menarche is earlier, then this has long been established
25 as a risk factor for breast cancer. It is simply another
26 causative link. The obesity link is quite solid. This is
27 another one where there is a substantial body of evidence
28 as well.
29
30 Q. Do you know whether it is the diet eaten at the time of
31 menarche that is the problem or just before it, or the
32 diet eaten as a young child from a young age?
33 A. The age of menarche will be influenced by the diet
34 that precedes it.
35
36 Q. Do you mean immediately precedes it?
37 A. Yes, but we are not speaking individual meals here.
38 We are speaking the overall ----
39
40 MR. JUSTICE BELL: You are not speaking of six months before;
41 you are speaking of a longer period or can you just not
42 say?
43 A. I would want to review some of these studies to give
44 you a definite answer, but what we do know is that the
45 diet will alter oestrogen levels within a matter of a
46 couple of weeks of changing the overall diet. However,
47 there is no point in life when diet stops altering
48 oestrogen levels in women, which is by way of saying that
49 -- this, by the way, probably may account for the link
50 between early menarche and breast cancer.
51
52 It may well be there is nothing special about early
53 menarche itself that causes breast cancer, although it may
54 be. It is quite possibly the same high fat diet that
55 causes menarche to occur earlier is basically affecting
56 all sorts of hormonal functions, including cancer risk.
57
58 MR. MORRIS: Just to clarify this position of how long you have
59 to be on a diet to influence the age of menarche,
60 presumably, if you are on a diet for two weeks, it will
