Because L-histidine is an essential amino acid, the body doesnt make it naturally.
However, there is very little evidence to support the efficacy of histidine supplementation.
That means some supplement products may not contain what the label says.
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No supplement is intended to treat, cure, or prevent disease.
An older study found no benefit overall from L-histidine supplementation.
Heart Disease Prevention
There is not enough evidence that L-histidine supplementation alone will prevent heart disease.
L-histidine is one amino acid that makes up the dipeptide carnosine.Carnosinesupplementation has been studied in heart disease prevention.
L-Histidine Deficiency
An L-histidine deficiency is possible but rare.
A negative nitrogen balance represents net protein breakdown in the body.
L-histidine-deficient individuals have low plasma levels of histidine and may experience atopic dermatitis.
They may also have low hemoglobin levels andanemia.
Amino acid profiles in the blood can be measured, but this is rarely done.
Any suspected single amino acid deficiencies can be corrected with adequate protein intake.
What Are the Side Effects of L-Histidine?
If consumed in excess, more side effects may occur.
Some have reported lower levels offolic acid, anorexia or reduced appetite, and a greater loss of zinc.
Taken in proper doses, L-histidine is considered safe for most people.
For supplementation, there is not enough information to recommend a specific dose.
Most people consume more histidine than required through diet alone.
What Happens if I Take Too Much L-Histidine?
There are no reports of L-histidine toxicity.
Also, there is no tolerable upper limit (TUL) established.
How to Store L-Histidine
It is best to follow manufacturer directions for proper storage of supplements.
As always, store medications and supplements out of the reach of children and pets to prevent accidental consumption.
Since amino acids combine to form proteins, any protein supplement or powder will also provide L-histidine.
Be sure to read supplement fact labels to know how much L-histidine you are taking from all sources.
When looking for supplements, look for ones that have been independently tested.
Supplements with seals from USP, ConsumerLabs, and NSF have been independently tested.
Summary
L-histidine is an essential amino acid.
Assuming adequate protein intake, deficiency is rare, and single amino acid supplementation is usually not needed.
You will get enough L-histidine if you consume the right amount of protein.
L-histidine supplementation has been marketed for several conditions, but not enough research supports its use.
Therefore, using L-histidine supplements to self-treat any health condition is not recommended.
Always consult your healthcare provider before starting a new supplement.
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Thalacker-Mercer AE, Gheller ME.Benefits and adverse effects of histidine supplementation.J Nutr.
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doi:10.1093/jn/nxaa229
National Library of Medicine.Protein and Amino Acids.In: Recommended Dietary Allowances.
