The China Study by Thomas Campbell

364

ci. o

C-

o o

o 0'

o

THE CHINA STUDY

CHART C.2: WORLDWIDE DISTRIBUTION

OF MS FOR 120 COUNTRIES

180 ,-------------------------------------------~

160

140

120

100

80

60

40

(^20) •

• o ~--_r--~----~--_rL-~ .. --~--_r--~
  South 80
  Latitude

60 40 20 o 20

Degrees Latitude

40 60 80 North

Latitude

more MS as one goes farther south (r=91 %). 15 MS is about sevenfold
greater in southern (43'S) than in northern Australia (19'5).16
A lack of sunshine, however, is not the only factor related to these
diseases. There is a larger context. The first thing to note is the control
and coordination of these vitamin D-related reactions. Control operates
at several places in this network, but, as I already said, it is the conver-
sion of storage vitamin D into the supercharged 1,25 D in the kidneys
that is especially critical. In considerable measure, this control is exer-
cised by another complex network of reactions involving a "manager"-
type hormone produced by the parathyroid gland located in our neck
(Chart C.3).
When, for example, we need more 1,25 D, parathyroid hormone in-
duces the kidney enzyme activity to produce more 1,25 D. When there
is enough 1,25 D, parathyroid hormone slows down the kidney enzyme