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Phenylketonuria

Also indexed as:Folling’s Disease, PKU
Early diagnosis is key to treating PKU, a rare genetic disorder that results in an amino acid imbalance in the body. According to research or other evidence, the following self-care steps may be helpful.
SupplementAmountWhy
Branched-Chain Amino Acids
Take under medical supervision: 150 mg daily per 2.2 lbs (1 kg) of body weight each of valine and isoleucine, and 200 mg daily per 2.2 lbs (1 kg) of body weight of leucine2 stars[2 stars]
Regular use of branched-chain amino acids (BCAAs) may improve mental functioning.
Fish Oil
125 mg of oil or 15 mg of docosahexaenoic acid per 2.2 lbs (1 kg) of body weight daily2 stars[2 stars]
The PKU diet is low in fatty acids, some of which are essential for proper brain development. Supplementing with fish oil may improve the deficiency.
L-Tyrosine
Consult a qualified healthcare practitioner2 stars[2 stars]
Supplementing with L-Tyrosine may help prevent a deficiency caused by the PKU diet and improve behavoir.
Selenium
Adolescents and adults: 55 mcg daily; for infants and children: 15 to 40 mcg daily, according to age2 stars[2 stars]
Selenium deficiency may develop on the PKU diet, and supplementation may help correct this.
Vitamin K
Refer to label instructions 1 star[1 star]
People with PKU may be deficient in vitamin K, due to the restricted PKU diet. Supplementing with vitamin K may correct a deficiency.
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Our proprietary “Star-Rating” system was developed to help you easily understand the amount of scientific support behind each supplement in relation to a specific health condition. While there is no way to predict whether a vitamin, mineral, or herb will successfully treat or prevent associated health conditions, our unique ratings tell you how well these supplements are understood by some in the medical community, and whether studies have found them to be effective for other people.

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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.