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ECA

ECA stands for Ephedrine, Caffeine and Aspirin; these compounds were found to be synergistic for fat loss, and isolating ephedrine from the Ephedra Sinicus plant and putting it into ECA appears to be quite an effective method of fat loss and neural stimulation.

Our evidence-based analysis on eca features 20 unique references to scientific papers.

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Summary of ECA

Primary information, health benefits, side effects, usage, and other important details

The ECA stack is a commonly used fat burning stack consisting of Ephedrine, Caffeine, and Aspirin.

The main component, Ephedrine, is the main active ingredient for weight loss and the caffeine augments its efficacy. The aspirin is added to prevent blood clotting (which may be a side effect of ephedrine) and to aid in the signal transduction of ephedrine via prostaglandin inhibition.

Some proponents of the ECA stack recommend replacing the Aspirin in the stack with either Fish Oil or White willow bark, as Aspirin is linked to various organ side effects and the previous two compounds share the same anti-clotting mechanisms.

Studies have shown that the combination of Ephedrine and Caffeine is superior for fat loss than taking each individually.[1][2][3] As ephedrine can increase heart rate and caffeine may increase blood pressure (in a naive user), the combination tends to have an additive rather than synergistic toxicological profile.[4]

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Human Effect Matrix

Unlocked for Examine members

The Human Effect Matrix summarizes human studies to tell you what effects ECA has on your body, how much evidence there is, and how strong these effects are.

Full details are available to Examine members.
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-c Notable Very High See 2 studies
The increase in metabolic rate seen with ephedrine is augmented with the inclusion of both aspirin and caffeine, hence its notable efficacy
grade-c Notable - See study
Due to both the increase in metabolic rate and reduction in appetite reported, there are notable weight reductions with the ECA stack
grade-c Minor - See study
Due to the ephedrine component, ECA may also reduce nasal congestion
grade-c Minor - See study
At least in persons with upper respiratory tract infections, a possible analgesic effect of ephedrine with aspirin exists
grade-c - - See study
No significant alterations in blood glucose noted with ECA supplementation
grade-c - - See study
No significant alterations in long term blood pressure, although acute spikes are possible due to the ephedrine and caffeine components
grade-c - - See study
Heart rate at rest is not affected by ECA supplementation and may indirectly be lowered secondary to weight loss. However, an acute increase in heart rate is possible from the stimulatory effects of ephedrine
grade-c - - See study
No significant alterations in fasting insulin reported
grade-c - - See study
No significant influence on total cholesterol levels

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Frequently Asked Questions and Articles on ECA

Do I need to cycle ephedrine?
Surprisingly, ephedrine does not appear to need cycling for the fat burning aspect of it (it may for neurological stimulation and appetite suppression). If using an ECA stack, however, the caffeine may need to be cycled

Things to Note

Primary Function:

Also Known As

Ephedrine/Caffeine/Aspirin, ECA Stack, EC Stack

Caution Notice

The ECA stack is a classical example of combining synergistic stimulants, and thus should be proceeded with caution in somebody not used to either stimulant in these doses.

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Click here to see all 20 references.