DRAFT Australian Dietary Guidelines - Eat For Health

pressure, and the effect is greater in those with hypertension than in those with normal blood
pressure [551-554].
There is evidence of a probable association between a diet low in sodium and a reduction in blood
pressure in children up to 18 years of age (Grade B, Section 13.2 in Evidence Report [14]) [553,
557, 558].
The Dietary Guidelines for Americans, 2010 draw similar conclusions regarding the relationship
between sodium and blood pressure. They state ‘a strong body of evidence has documented that
in adults, as sodium intake decreases, so does blood pressure. A moderate body of evidence has
documented that as sodium intake decreases, so does blood pressure in children, from birth to 18
years of age’ [143]. They also note that people with hypertension, diabetes and chronic kidney
disease are more sensitive to sodium than healthier younger people, and that sensitivity to sodium
increases with age.
Cardiovascular disease: Despite extensive research on the relationship between sodium and
blood pressure, few long term studies have examined changes in sodium intake and changes in
cardiovascular morbidity and mortality. Past studies have mainly included subjects with
hypertension. The evidence suggests that reducing sodium intake by about 1,000mg/day is
associated with reduced risk of cardiovascular events (Grade C, Section 13.4 in Evidence Report
[14]) [552, 559-564]. The results are consistent with results from drug trials that have shown that
reductions in high blood pressure also lead to reductions in adverse cardiovascular outcomes
[565, 566].
3.2.2.2 Cancer
Evidence of a probable association between consumption of salt and salt-preserved foods with
gastric cancer was found in the systematic review prepared as the background paper for the Joint
WHO/FAO Expert Consultation on diet, nutrition and prevention of chronic diseases [567]. This
association was described as convincing by the WCRF [42]. The WCRF also reported convincing
evidence of an association between processed meats (meat preserved by smoking, curing, salting
or addition of chemical preservatives such as nitrites) and increased risk of colorectal cancer [42]
but it is unclear whether the responsible factor in the food is the salt, other components such as
nitrites, or a combination of these factors.
3.2.2.3 Other conditions
Bone health: Evidence suggesting an association between a low sodium diet and markers of bone
health in postmenopausal women is inconclusive (Section 13.3, Evidence Report [14]).
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