The use of free form amino acids to support or treat addictions to sugar or refined carbohydrates is primarily justified by a limited body of scientific evidence, though some practices are influenced by tradition or integrative medicine theories. Amino acids such as L-tyrosine, L-glutamine, and 5-HTP (a precursor of serotonin) are sometimes recommended based on the hypothesis that imbalances in brain neurotransmitters—specifically dopamine and serotonin—may drive cravings and addictive behaviors, including those for sugar and carbohydrates.

Some small clinical studies and preclinical research suggest that supplementation with certain amino acids may help modulate neurotransmitter levels and reduce cravings. For instance, L-glutamine has been studied for its potential to reduce sugar cravings, and L-tyrosine is thought to support dopamine production, which may be depleted in addictive states. However, the quality and quantity of evidence are limited, with most studies being small, short-term, or lacking rigorous controls. Systematic reviews and large-scale clinical trials are generally lacking, and the mechanism by which free form amino acids would specifically reduce cravings for sugar or refined carbohydrates remains largely theoretical.

In summary, while there is some preliminary scientific rationale and a few supportive studies, the evidence base is not robust, and the use of free form amino acids for treating sugar or refined carbohydrate addiction should be considered experimental. More high-quality research is needed to establish efficacy and safety.