Day 033 - 10 Oct 94 - Page 34
1 calories and carbohydrate are expended simply in trying to
2 make fat from it.
3
4 In addition to that, a high fat -- when fat is consumed it
5 has no influence on body metabolism. In other words, fat
6 does not increase the speed with which the cells of the
7 body consume calories, consume energy. On the other hand,
8 carbohydrates do. When a diet is rich in carbohydrates --
9 here I mean the complex carbohydrates that are in
10 potatoes, rice, pasta, vegetables, beans and so forth --
11 when individuals are on high carbohydrate diets their
12 metabolism is measurably increased.
13
14 Without getting into great complexity about the mechanisms
15 for that, certain hormonal changes, beneficial hormonal
16 changes, have been identified that come from individuals
17 consuming high carbohydrate diets. More adrenaline levels
18 are elevated, the levels of active thyroid hormone are
19 elevated.
20
21 The reason I am giving this detailed discussion is to show
22 that there is clearly a causal link between a high fat
23 diet and obesity, and the causal link between obesity and
24 hypertension is quite well accepted, and I cannot imagine
25 anyone would challenge that.
26
27 In addition to that, however, when patients are
28 hypertensive and put on any sort of weight reduction diet,
29 very, very commonly their blood pressure drops. So it is
30 beyond any reasonable doubt that a high fat diet has a
31 causal link with hypertension mediated by its effect on
32 obesity. That is by no means the only link, however, but
33 that is one causal.
34
35 Q. What about the sodium link?
36 A. Sodium, in general, has a tendency to hold water and
37 when individuals are on high sodium diets the simple
38 explanation is that it tends to draw water into the blood
39 vessels raising the pressure of fluid within the blood.
40 When individuals reduce their sodium intake their blood
41 pressure falls and, contrarily, if an individual has
42 hypertension, if you increase their sodium intake their
43 blood pressure will be driven up.
44
45 Q. So the link which you have identified between hypertension
46 and salt or sodium, what kind of link is that?
47 A. Well, it is a causal link.
48
49 Q. Is hypertension a serious disease?
50 A. Very much so. When you have excessive pressure in
51 your arteries, that pressure accelerates atherosclerosis;
52 the formation of the plaques in the arteries that causes
53 heart disease, or that is what we call heart disease, when
54 it occurs in the coronary arteries. When the arteries
55 that go up the neck into the head and reach the brain are
56 under higher than normal pressures, the likelihood of a
57 haemorrhagic stroke is increased. Hypertension is a well
58 known risk factor for stroke. So, yes, hypertension is a
59 very serious condition.
60
