On Fri, 27 Aug 1999, alexs wrote:
> > 2. It is well documented in the medical and health literature that excess
> > fat in the blood and tissues makes the body "insulin-resistant" .
>
> I would suspect that this "well documented" factoid in fact has little real
> documentation to back it up. Might one presume to ask for citations
> or a even a URL to follow?
There is a fair amount of evidence to support that claim that
saturated fats contribute to insulin resistance. I have appended
some references. The question, however, is whether insulin
resistance is a problem if the diet is consistently low-carb, and
moderate-protein. It seems to me that insulin resistance is a
problem only when insulin levels become raised in response to
abundant carbs or excess protein.
Todd Moody
[log in to unmask]
Title
Relation between plasma phospholipid saturated fatty acids
and hyperinsulinemia.
Author
Folsom AR; Ma J; McGovern PG; Eckfeldt H
Address
Division of Epidemiology, School of Public Health, University of
Minnesota,
Minneapolis 55454-1015, USA.
Source
Metabolism, 1996 Feb, 45:2, 223-8
Abstract
We determined whether plasma phospholipid fatty acid levels,
an indicator of fatty acid composition in the diet, are
associated with fasting serum insulin concentrations (a
marker of insulin resistance). We examined cross-sectionally
4,304 middle-aged adults free of diabetes. Plasma fatty acid
composition was quantified by gas chromatography. Fasting
insulin was strongly and positively associated with the
saturated fatty acid percentage in plasma phospholipids,
moderately and inversely associated with the monounsaturated
percentage, and not appreciably associated with the
polyunsaturated percentage. Fasting insulin adjusted for age,
smoking status, alcohol consumption, and sports
participation, for example, was 29% higher in men and 33%
higher in women per 1.9% greater level of saturated fatty
acids (the interquartile range). After adjustment for body
mass index (BMI) and other covariates, these estimates were
12% and 15% (P < .01 for the difference from zero). A 1.9%
greater increment in saturated fatty acid level was also
associated with a 2.4-fold higher odds of hyperinsulinemia
(fasting insulin > or = 143.5 pmol/L). These data are
consistent with studies showing that fatty acid composition
of cell membranes modulates insulin action, and support the
hypothesis that increased habitual saturated fat intake or a
related dietary pattern is a risk factor for
hyperinsulinemia.
Title
Insulin resistance, hyperinsulinemia, and cardiovascular
disease. The need for novel dietary prevention strategies
[editorial]
Author
Rupp H
Source
Basic Res Cardiol, 1992 Mar-Apr, 87:2, 99-105
Abstract
Insulin resistance associated with hyperinsulinemia
(metabolic syndrome) emerged in recent years as an important
health risk which is present in approximately 25% of the
normal population in western industrialized societies.
Insulin resistance as assessed for the whole body arises from
a reduced glucose utilization of skeletal muscle. If the
metabolic syndrome persists over a prolonged period of time,
detrimental influences on the cardiovascular system become
apparent involving diabetes mellitus, hypertension, and
arteriosclerosis. Of particular pathogenic relevance is an
unbalanced influence of insulin arising either from a
diminished or enhanced insulin action depending on whether
the various tissues of the body exhibit a reduced or
unchanged insulin sensitivity. Since insulin resistance and
hyperinsulinemia appear to be affected by various lifestyle
factors, the unique opportunity exists of reducing
cardiovascular mortality by correcting this syndrome at a
time when degenerative changes have not occurred in the
cardiovascular system. Of great importance is the finding
that dietary factors can have a modulatory action on insulin
sensitivity. In animal experiments, an increased intake of
(saturated) fat and refined carbohydrates increased insulin
resistance. Since psychosocial distress is expected to be
associated with a sustained activation of the sympathoadrenal
axis, it is likely also to aggravate the metabolic syndrome.
A factor with a beneficial action appears to be physical
exercise. In view of the high incidence of cardiovascular
diseases, further research on lifestyle factors with an
insulin-sensitizing or insulin-desensitizing action is
required. Of prime importance is the reevaluation of
established dietary recommendations and diets should be
designed which take into account the individual
cardiovascular risk factor profile.
Title
Saturated fat intake and insulin resistance in men with
coronary artery disease. The Stanford Coronary Risk
Intervention Project Investigators and Staff.
Author
Maron DJ; Fair JM; Haskell WL
Address
Division of Cardiovascular Medicine, Stanford University
School of Medicine, Calif.
Source
Circulation, 1991 Nov, 84:5, 2020-7
Abstract
BACKGROUND. To determine whether there is an association
between diet and plasma insulin concentration that is
independent of obesity, we studied the relation of dietary
composition and caloric intake to obesity and plasma insulin
concentrations in 215 nondiabetic men aged 32-74 years with
angiographically proven coronary artery disease. METHODS AND
RESULTS. After adjusting for age, the intake of saturated
fatty acids and cholesterol were positively correlated (p
less than 0.05) with body mass index (r = 0.18, r = 0.16),
waist-to-hip circumference ratio (r = 0.21, r = 0.22), and
fasting insulin (r = 0.26, r = 0.23). Carbohydrate intake was
negatively correlated with body mass index (r = -0.21),
waist-to-hip ratio (r = -0.21), and fasting insulin (r =
-0.16). Intake of monounsaturated fatty acids did not
correlate significantly with body mass index or waist-to-hip
circumference ratio but did correlate positively with fasting
insulin (r = 0.24). Intake of dietary calories was negatively
correlated with body mass index (r = -0.15). In multivariate
analysis, intake of saturated fatty acids was significantly
related to elevated fasting insulin concentration
independently of body mass index. CONCLUSIONS. These
cross-sectional findings in nondiabetic men with coronary
artery disease suggest that increased consumption of
saturated fatty acids is associated independently with higher
fasting insulin concentrations.
Metabolism 1996 Feb;45(2):223-228
Relation between plasma phospholipid saturated fatty acids and
hyperinsulinemia.
Folsom AR, Ma J, McGovern PG, Eckfeldt H
Division of Epidemiology, School of Public Health, University of
Minnesota, Minneapolis 55454-1015, USA.
We determined whether plasma phospholipid fatty acid levels,
an indicator of fatty acid composition in the diet, are
associated with fasting serum insulin concentrations (a
marker of insulin resistance). We examined cross-sectionally
4,304 middle-aged adults free of diabetes. Plasma fatty acid
composition was quantified by gas chromatography. Fasting
insulin was strongly and positively associated with the
saturated fatty acid percentage in plasma phospholipids,
moderately and inversely associated with the monounsaturated
percentage, and not appreciably associated with the
polyunsaturated percentage. Fasting insulin adjusted for
age, smoking status, alcohol consumption, and sports
participation, for example, was 29% higher in men and 33%
higher in women per 1.9% greater level of saturated fatty
acids (the interquartile range). After adjustment for body
mass index (BMI) and other covariates, these estimates were
12% and 15% (P < .01 for the difference from zero). A 1.9%
greater increment in saturated fatty acid level was also
associated with a 2.4-fold higher odds of hyperinsulinemia
(fasting insulin > or = 143.5 pmol/L). These data are
consistent with studies showing that fatty acid composition
of cell membranes modulates insulin action, and support the
hypothesis that increased habitual saturated fat intake or a
related dietary pattern is a risk factor for
hyperinsulinemia.
Diabetologia 1997 Apr;40(4):430-438
High saturated fat and low starch and fibre are associated with
hyperinsulinaemia in a non-diabetic population: the San Luis
Valley Diabetes Study.
Marshall JA, Bessesen DH, Hamman RF
Department of Preventive Medicine and Biometrics, University of
Colorado School of Medicine, Denver, USA.
A geographically based sample of 1069 Hispanic and
non-Hispanic white persons aged 20-74 years, living in
southern Colorado and who tested normal on an oral glucose
tolerance test (World Health Organization criteria) were
evaluated to determine associations of dietary factors with
fasting serum insulin concentrations. Subjects were seen for
up to three visits from 1984 to 1992. A 24-h diet recall and
fasting insulin concentrations were collected at all visits.
In longitudinal data analysis, lower age, female gender,
Hispanic ethnicity, higher body mass index, higher waist
circumference, and no vigorous activity were significantly
related to higher fasting insulin concentrations. High total
and saturated fat intake were associated with higher fasting
insulin concentrations after adjusting for age, sex,
ethnicity, body mass index, waist circumference, total energy
intake and physical activity. Dietary fibre and starch intake
were inversely associated with fasting insulin
concentrations. No associations with fasting insulin
concentrations were observed for monounsaturated fat,
polyunsaturated fat, sucrose, glucose and fructose intake.
Associations were similar in men and women and for active and
inactive subjects, though associations of fibre and starch
intake with insulin concentrations were strongest in lean
subjects. These findings support animal studies and a limited
number of human population studies which have suggested that
increased saturated and total fat intake and decreased fibre
and starch intake increase fasting insulin concentrations and
may also increase insulin resistance. These findings, which
relate habitual macronutrient consumption to
hyperinsulinaemia in a large population, may have
implications for studies attempting primary prevention of
non-insulin-dependent diabetes mellitus.
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