BackgroundThe relationship between macronutrients and cardiovascular disease and mortality is
controversial. Most available data are from European and North American populations
where nutrition excess is more likely, so their applicability to other populations
is unclear.
MethodsThe Prospective Urban Rural Epidemiology (PURE) study is a large, epidemiological
cohort study of individuals aged 35–70 years (enrolled between Jan 1, 2003, and March
31, 2013) in 18 countries with a median follow-up of 7·4 years (IQR 5·3–9·3). Dietary
intake of 135 335 individuals was recorded using validated food frequency questionnaires.
The primary outcomes were total mortality and major cardiovascular events (fatal cardiovascular
disease, non-fatal myocardial infarction, stroke, and heart failure). Secondary outcomes
were all myocardial infarctions, stroke, cardiovascular disease mortality, and non-cardiovascular
disease mortality. Participants were categorised into quintiles of nutrient intake
(carbohydrate, fats, and protein) based on percentage of energy provided by nutrients.
We assessed the associations between consumption of carbohydrate, total fat, and each
type of fat with cardiovascular disease and total mortality. We calculated hazard
ratios (HRs) using a multivariable Cox frailty model with random intercepts to account
for centre clustering.
FindingsDuring follow-up, we documented 5796 deaths and 4784 major cardiovascular disease
events. Higher carbohydrate intake was associated with an increased risk of total
mortality (highest [quintile 5] vs lowest quintile [quintile 1] category, HR 1·28 [95% CI 1·12–1·46], ptrend=0·0001) but not with the risk of cardiovascular disease or cardiovascular disease
mortality. Intake of total fat and each type of fat was associated with lower risk
of total mortality (quintile 5 vs quintile 1, total fat: HR 0·77 [95% CI 0·67–0·87], ptrend<0·0001; saturated fat, HR 0·86 [0·76–0·99], ptrend=0·0088; monounsaturated fat: HR 0·81 [0·71–0·92], ptrend<0·0001; and polyunsaturated fat: HR 0·80 [0·71–0·89], ptrend<0·0001). Higher saturated fat intake was associated with lower risk of stroke (quintile
5 vs quintile 1, HR 0·79 [95% CI 0·64–0·98], ptrend=0·0498). Total fat and saturated and unsaturated fats were not significantly associated
with risk of myocardial infarction or cardiovascular disease mortality.
InterpretationHigh carbohydrate intake was associated with higher risk of total mortality, whereas
total fat and individual types of fat were related to lower total mortality. Total
fat and types of fat were not associated with cardiovascular disease, myocardial infarction,
or cardiovascular disease mortality, whereas saturated fat had an inverse association
with stroke. Global dietary guidelines should be reconsidered in light of these findings.
FundingFull funding sources listed at the end of the paper (see Acknowledgments).
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