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Klinisk Biokemi i Norden · 2 2017
seen during a fat tolerance test
27,28
; however, the
increase in plasma triglycerides observed after habitual
food intake in most individuals is much less than that
observed during a fat tolerance test
5,6,11,29-32
. Also, as
LDL cholesterol is often calculated by the Friedewald
equation, which includes the triglyceride concentra-
tion, calculated LDL cholesterol has been thought
to be affected substantially by food intake; however,
directly measured and calculated LDL cholesterol
are similar using both fasting and nonfasting lipid
profiles (Figure 2)
19,20
. If this Friedewald equation is
employed, there may be some underestimation of LDL
cholesterol when chylomicrons are present, which may
even be circumvented if a modification of this equa-
tion is used
33
. Also, many randomized lipid-lowering
trials have used fasting lipid measurements and, in
order to follow evidence-based practice, fasting blood
sampling has often been the standard in everyday risk
assessment. However, numerous population-based
studies and at least three major statin trials used ran-
dom, nonfasting blood sampling, providing a robust
evidence base for a change in the conventional practice
of using fasting samples.
Influence of food intake on the plasma lipid
profile
Several large-scale, population-based studies and
registries including children, women, men, and
patients with diabetes have now established that
plasma lipids and lipoproteins only change modestly
in response to habitual food intake
5,6,11,30,31
; this app-
lies to the majority of individuals, but rarely some
exhibit exaggerated responses. These studies were the
Women’s Heath Study from the US, the Copenhagen
General Population Study from Denmark, the Natio-
nal Health and Nutrition Examination Survey from
the US, and the Calgary Laboratory Services from
Canada. Among all studies comparing nonfasting
with fasting lipid profiles, minor increases in plasma
triglycerides and minor decreases in total and LDL
cholesterol concentrations were observed, with no
change in HDL cholesterol concentrations. These
minor and transient changes in lipid concentrations
appear to be clinically insignificant; however, Lang-
sted et al observed a transient drop in LDL cholesterol
concentration of 0.6 mmol/L(23mg/dL) at 1-3 hours
after a meal in diabetic patients, which could be of
clinical significance
34
, particularly if this is used as
an argument to withhold statins in a given patient. Of
note, the reduction in total and LDL cholesterol at 1-3
hours after the last meal observed in individuals with
and without diabetes became statistically insignificant
after adjusting for plasma albumin concentration as
a marker of fluid intake
5,11
; therefore, such a drop in
total and LDL cholesterol is unrelated to food intake,
noting that a similar drop may even be observed in a
fasting lipid profile, since water intake is allowed ad
libitum before a fasting blood test
4
.
For the purpose of the present joint consensus
statement, we updated the analyses of Langsted et
al
5,35
(Figure 3), based on the Copenhagen General
Population Study and including 92,285 men and
women from the Danish general population. As
in previous reports
5,6,11,30,31,35
, the maximal mean
changes at 1-6 hours after habitual meals were con-
sidered clinically insignificant at +0.3mmol/L(26mg/
dL) for triglycerides, -0.2mmol/L(8mg/dL) for total
Increased
N=92,285
Triglycerides
Total cholesterol
LDL cholesterol
Remnant cholesterol
NonHDL cholesterol
Lipoprotein(a)
Apolipoprotein B
HDL cholesterol
Apolipoprotein A1
+0.3 +26
-0.2 -8
-0.2 -8
+0.2 +8
-0.2 -8
No change
No change
No change
No change
mmol/L mg/dL
Decreased
Maximal mean change after habitual food intake
Figure 3
Increas d
N=92,285
Triglycerides
Total chol
l
LDL cholesterol
Remnant cholesterol
NonHDL cholesterol
Lipoprotein(a)
Apolipoprotein B
HDL cholesterol
Apolipopr tein 1
+0.3 +26
-0.2 -8
-0.2 -8
+0.2 +8
-0.2 -8
No change
No change
No change
No change
mmol/L mg/dL
ecreased
axi al mean change after habitual food intake
Fi ure 3
Figure 3. Maximal mean changes at 1-6 hours after habitual
food intake of lipids, lipoproteins, and apolipoproteins as
part of standard and expanded lipid profiles in individuals
in the Danish general population. Calculated remnant cho-
lesterol is nonfasting total cholesterol minus LDL cholesterol
minus HDL cholesterol. Calculated nonHDL cholesterol
is total cholesterol minus HDL cholesterol. Adapted and
updated from Langsted et al
5,35
, based on 92,285 individuals
from the Copenhagen General Population Study recruited in
2003 through 2014. Of all participants, 12% were receiving
statins. Values in mmol/L were converted to mg/dL by multi-
plication with 38.6 for cholesterol and by 88 for triglycerides.
