In an effort to address these issues, Norris et al in their study on obese
post menopausal women with Type 2 Diabetes Mellitus analyzed the effects of
dietary conjugated linoleic acid (CLA) and
safflower oil (SFA) on body composition.
Safflower oil is
a commonly used cooking oil and conjugated linoleic acid is a compound
naturally found in meat and dairy foods. CLA has
been found to reduce weight and adipose tissue in various clinical trials and
has been extensively promoted as a weight loss supplement.
Both the dietary oils and dairy products are
composed of polyunsaturated fatty acids, which are considered as "good fats"
and are associated with various health benefits. They are rich in the essential
omega - 6 fatty acids (linoleic acid). A commercial mixture of CLA oil is used
in most studies as the naturally occurring CLA from ruminant meats and dairy
products is low in its adipose-lowering isomer. Safflower oil is a very popular
cooking medium in the west.
study, fifty-five postmenopausal women less than 70 years with Type 2 Diabetes
Mellitus were recruited. The goal
of the study was to compare the effects of CLA and SAF on body weight,
body composition, and adipose tissue distribution.
were randomly assigned to 2 groups in order to
determine which supplement they would be taking first (CLA or SAF). The
initial diet period was of 16 wk, followed by a 4-wk washout period and a
second 16-wk diet period.
Subjects consumed 8 dietary oil capsules daily. Each CLA capsule
contained 1.0 g CLA-80 oil and each SAF capsule contained 1.0 g SAF oil. A
total of 8g dietary oil was consumed daily by all subjects.
continued with their hypoglycemic drugs throughout the study. Women were asked
to fast and abstain from taking the diabetes medications and treatment capsules
the morning of each study visit. Dual-energy X-ray absorptiometry was used to
assess the body composition.
With CLA supplementation a significant
decrease in BMI was observed during the last half of each diet period. Total
adipose mass was seen to significantly decrease with no effect on fasting
On the other hand SAF significantly
reduced trunk adipose mass and increased lean tissue.. SAF also significantly
decreased the fasting glucose.
Weight gain, increase in the body fat levels and
abdominal fat accumulation are common post menopause. These changes increase
the risk of developing heart ailments and metabolic syndrome. This
particular study remains the first to show that even a modest amount (1-2/3
teaspoon or 8 mL) of linoleic acid-rich oil can have a significant effect on
body composition. Postmenopausal women are at
risk of losing lean tissue mass. But supplementation with CLA and safflower oil
on the contrary did not cause a loss of the same. Rather SAF was seen to
increase the total lean tissue.
women are at a risk of developing central obesity and insulin resistance.
However with SAF supplementation the study reported decreased trunk adipose
mass and lowered glycemia.
aside the study limitations and the unfavorable events, the findings clearly
suggest that dietary supplementation with oils rich in n−6 linoleic acid helps
to positively affect body composition and improve glycemic control
significantly. The study thus brings forth various important findings that
could help manage the debilitating lifestyle related health threats.
Discovering and implementing dietary methods to reduce the risk of heart
disease, diabetes and its comorbidities can be a boon to the community.
The study suggests that even a modest dose of 6.4
g/d, CLA can have a significant effect on body weight and fat mass.
Use of lower doses of CLA over a period of time can
actually prove to be an effective weight-loss aid.
study, CLA did not appear to affect the fat burning hormones, whereas SAF
increased the hormone called as adiponectin which might have been responsible
for burning dietary fats. Previously conducted
work on animals suggests that in the case of CLA, the fatty acid allows the
body to burn calories in a heat producing way.
add that long term use of any supplements that lower body fat brings forth
various safety issues and questions. They suggest, that if the fat that leaves
fat tissues is not utilized, then it deposits in the liver or muscles leading
to insulin resistance and diabetes. Therefore the exact mechanism behind the
fat burning and channelizing further needs to be understood.
CLA and the linoleic acid in safflower oil
cannot be produced by the human body and must be obtained from food, or dietary
- Conjugated Linoleic Acid
- Safflower oil
Norris LE et
al. Comparison of dietary conjugated linoleic acid with safflower oil on body
composition in obese postmenopausal women with type 2 diabetes mellitus. The American Journal of Clinical Nutrition, 2009.