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Fat Oxidation

Fat Oxidation is the percentage of caloric expenditure that is derived from fatty acids (the alternative being mostly from glucose); it is independent of actual metabolic rate.

Research analysis led by Kamal Patel.
All content reviewed by the Examine.com Team. Published: Dec 12, 2012
Last Updated:

Human Effect Matrix

The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what supplements affect fat oxidation
Grade Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
Notes
grade-a Minor Very High See all 8 studies
There appears to be a slight but unreliable increase in fat oxidation (percentage of overall calories used coming from fatty acids rather than glucose) associated with consumption of green tea catechins
grade-b Minor Low See all 3 studies
In prolonged exercise and somewhat related to the antifatigue effects, an increase in fat oxidation is noted with BCAA supplementation; this is thought to be related to the glycogen preserving effects of BCAAs.
grade-b Minor Very High See all 3 studies
An increase in fat oxidation appears to be apparent (assessed via increased serum glycerol and free fatty acids) which is thought to be secondary to increases in adrenaline
grade-b Minor High See all 3 studies
There is a possible increase in fat oxidation rates seen during rest, with one study confirming it during exercise; this may not coincide with an increase in metabolic rate.
grade-b - Very High See all 3 studies
Colostrum does not influence fat oxidation rates or glucose expenditure during exercise any differently than other protein sources such as whey.
grade-b - High See all 3 studies
Rates of fat oxidation appear unaffected following carnitine supplementation
grade-c Minor - See study
Some biomarkers of hepatic fat oxidation increased at rest, no indication as to the potency of this relative to reference drugs.
grade-c Minor - See study
May influence fat oxidation, but more evidence is required.
grade-c Minor Very High See 2 studies
Some studies have noted an increase in fat oxidation during exercise; no current studies conducted at rest
grade-c Minor - See 2 studies
An increase in fat oxidation has been noted at rest with supplemental sodium bicarbonate which contributed solely to the increase in metabolic rate
grade-c Minor - See study
Nothing remarkable in the one study on fat oxidation rates during exercise.
grade-c Minor - See study
There may be a reduction in fat oxidation rates when pharmacological doses of niacin are consumed by otherwise healthy subjects, although no changes in the metabolic rate occur due to an increase in the rate of glucose oxidation.
grade-c - - See study
grade-c - - See study
grade-c - Very High See 2 studies
Fat oxidation (percent of energy derived from fatty acids relative to glucose) does not appear to be influenced following supplementation of chromium.
grade-c - Very High See all 3 studies
The rate of fat oxidation relative to carbohydrates does not appear to be altered in response to supplementation of cocoa flavanols.
grade-c - - See 2 studies
grade-c - - See study
When nicotine increases metabolic rate, there is no change in rates of fat or glucose oxidation.
grade-c - - See study
Rates of fat oxidation during exercise appear unchanged
grade-c - - See study
No significant influence on fat oxidation during exercise
grade-c - - See study
No significant alterations in fat oxidation noted with quercetin supplementation
grade-c - - See study
Resting fat oxidation does not appear to be altered when 150mg resveratrol is taken shortly after exercise.
grade-c - - See study
grade-c - Very High See 2 studies
No significant influence on fat oxidation
grade-d Minor - See study
An increase in fat oxidation (percentage of energy being taken from fat tissue) has been noted with fish oil supplementation
grade-d Minor - See study
Appears to increase the percentage of calories derived from lipids in obese persons; no comparator.
grade-d - - See study
Despite improvements seen in VO2 max and endurance capacities in this study, the respiratory exchange ratio (indicative of fat oxidation) was not significantly influenced.