Day 252 - 20 May 96 - Page 16
1 stomach are leeched out of the intestine into the
2 bloodstream are they?
3 A. Yes.
4
5 Q. And then distributed by the circulation?
6 A. Yes.
7
8 Q. That is the sort of basic mechanics?
9 A. Yes. Carbohydrate tends to be digested fairly
10 rapidly.
11
12 Q. Yes.
13 A. And very simple carbohydrates like sugar would pass
14 into the circulation even more rapidly and be cleared more
15 rapidly. Fat digestion tends to be a fairly slow process,
16 it takes several hours, and with a huge meal -- as in the
17 previous paper -- it will take 4 hours. What happens is if
18 you take a blood sample from somebody an hour after a meal
19 containing fat, it is cloudy. All that means is that there
20 are tiny blobs of fat floating around in the blood. 3
21 hours later it is clear again, and all that means is that
22 the animal's tissue has removed all this fat from the
23 circulation and deposited it. What this paper suggests is
24 that habitually eating a high fat diet slows this process
25 down.
26
27 MR. RAMPTON: Does that matter?
28 A. Well, they suggest, and it is a suggestion, that this
29 reduced ability to clear triglycerides from the blood may
30 be associated with atherosclerosis. On the other hand, it
31 may not.
32
33 MR. JUSTICE BELL: It may be?
34 A. Associated with the process of atherosclerosis, this
35 persistent small elevation of blood lipids of a very large
36 fat load. I think it is interesting that in this document,
37 'Nutritional Aspects of Cardiovascular Disease', there is
38 no discussion at all of the role of triglycerides in the
39 development of atherosclerosis and certainly any experts I
40 have talked to about triglycerides as being a risk factor,
41 fat being a risk factor, the matter is very contentious,
42 there is no real clear-cut evidence that triglycerides are
43 part of the atherosclerosis process, unlike cholesterol.
44
45 MR. RAMPTON: Two questions only, Professor Naismith. First,
46 do you believe that what the abstract itself describes as
47 limited data in this -- you see the first two words say
48 'limited data is available', never mind the grammar, but
49 'limited data is available, compare it', and so on?
50 A. Yes.
51
52 Q. First question: do you believe that the limited data
53 disclosed or revealed by this study supports the conclusion
54 drawn in Professor Miller's letter?
55 A. No. I think one of the problems with studies of this
56 kind is that medical scientists, and I must admit to having
57 been guilty of this myself at times, in order to
58 demonstrate that something is happening tend to use very
59 unphysiological or abnormal conditions. If you want to
60 demonstrate an effect of a deficiency or an excess one
