CLA "Wow Give Me Some Of That!"
Conjugated linoleic acid (CLA) is quite possibly the supplement
of choice when looking for that weight-loss miracle pill. One
group of overweight women lost 9% body fat in one year's time
even though they didn't change their lifestyle or eating habits
in any way.
This is the first time CLA has been researched for it's effects
on body composition an the results are clearly remarkable.
Never heard of CLA?
CLA is a naturally occurring fatty acid found in meat and dairy
products. It is a popular dietary supplement benefiting people
who want to lose fat, maintain weight loss, lower blood
pressure, boost their immune system, retain lean muscle mass,
and control type 2 diabetes - the type of diabetes that is often
associated with obesity.
CLA comes in different concentrations. Products containing 80%
CLA are recommended to get maximum weight-loss results.
CLA has been shown to prevent heart disease and several types of
cancer. It also appears to enhance the immune system.
One study involving 180 overweight men and women, all between 25
and 30 BMI (body mass index). A BMI -- an indicator of body fat
-- over 25 has been linked to an increased risk of heart disease
and other medical problems, such as diabetes. The volunteers
were mostly female -- 149 women and 31 men.
Volunteers were assigned to three groups. The two groups taking
CLA got either the typical off-the-shelf pills (4.5 grams of 80%
CLA) daily or the syrup formulation (3.6 grams of 76% CLA
disguised in a capsule) daily. The third group took a placebo
capsule filled with olive oil daily.
Participants were not required to change their diet or exercise
habits. However, a nurse did give dietary and exercise advice
upon request. Daily calorie intake was similar among the three
groups; all volunteers reduced their calorie intake a little
during the study. All got about the same amount of exercise.
This strongly suggests that the observed effects of CLA on body
composition were independent of diet. The decreased calorie
intake may be partly due to the supplements and/or a reduced
appetite. Also, because volunteers kept a food diary, they
learned to cut food intake.
Several times during the 12-month study period, the study group
came to a clinic to have their weight, BMI, and blood checked.
They also completed questionnaires on their diet and exercise in
the previous two weeks.
At the end of one year:
Both CLA groups lost weight -- about 4 pounds; the placebo
group stayed the same.
The CLA syrup group had a 9% body fat loss; the CLA pill group
had 7% loss; the placebo group had no body fat loss.
Both CLA groups had similar improvements in muscle mass.
Regarding other risk factors:
The CLA pill group had slightly higher LDL bad cholesterol.
The CLA syrup group had slightly lower HDL good cholesterol.
Both CLA groups had higher lipoprotein levels, a marker of
inflammation and heart disease.
Both CLA groups had higher levels of leptin, a hormone thought
to be a heart disease marker.
Both CLA groups had higher white blood cell counts, which could
trigger damaging artery inflammation.
The CLA groups had only modest changes in blood sugar levels, a
marker for diabetes.
The results of this study corroborate and expand on the findings
of the previous short-term studies. Results show that the effect
is greatest in those with highest body mass index, especially
women with a 25 to 30 BMI.
As far as the heart disease risk factors, the variations seen in
the CLA groups are within normal physiological range. Increased
white blood cells may reflect the heightened immune response
that other studies have shown. In studies in Holland, CLA has
been shown to prevent some viral infections.
The mechanism(s) by which CLA decreases body fat mass and
increases lean muscle mass is not completely understood. CLA is
known to accumulate in tissues of animals and humans where it is
readily metabolized. CLA may trigger fat cell death, shrink fat
cells, or it may speed up metabolism to promote weight loss.