What is beta-alanine?

In one line

Beta-alanine is an amino acid that the body uses to make carnosine in muscle, which helps slow the muscle from turning acidic during very hard exercise.

What is beta-alanine?
The ingredient that makes you tingle
You often see the name beta-alanine on the labels of supplements taken before workouts. It is also well known as the ingredient that makes your face or hands tingle after you take it. Let's go step by step through what it is, what it does in the body and why it tingles.
In one line
The raw material for 'carnosine' in muscle
Beta-alanine is a kind of amino acid that the body uses as raw material for a substance in muscle called 'carnosine'. Carnosine helps muscles not tire as quickly during very hard exercise. Taking beta-alanine raises the carnosine in your muscles.
First, what are amino acids?
Beta-alanine is an amino acid that does not build protein
A protein is a long chain of tiny beads called 'amino acids', which come in 20 kinds. But some amino acids are not among these 20 and are not used to build protein. Beta-alanine is one of them, and the body makes small amounts of it in the liver.
What is carnosine?
Beta-alanine linked with histidine
Carnosine is a small substance made of two amino acids linked together: beta-alanine and one called 'histidine'. Most of the body's carnosine is in muscle. Of the two ingredients, beta-alanine is the one that tends to run short, so how much carnosine is made depends on how much beta-alanine there is.
What carnosine does
It soaks up the acid made during hard exercise
During very hard exercise, the inside of the muscle gradually turns acidic, toward the sour side. Muscle turning acidic is one of the reasons muscles tire. Carnosine soaks up this acid inside the muscle and slows the change toward acidic.
Where it comes from
The body makes a little, and meat provides some
The liver makes a little beta-alanine, and you also get it from eating chicken and other meat. The carnosine in meat is broken apart in the body before it reaches the muscle, and this releases beta-alanine. Muscle then uses that beta-alanine to make carnosine again.
Taking it as a supplement
Muscle carnosine rose sharply in 4 weeks
In studies, people took 4 to 6 g of beta-alanine a day, split into several doses. After 4 weeks of this, muscle carnosine rose to as much as about 1.6 times its starting level. It is not a one-time dose; it works by taking it steadily for several weeks to build it up in muscle.
Exercise where it helped
Very hard exercise lasting 1 to 4 minutes
Beta-alanine most clearly raised how long people could keep going in very hard exercise lasting about 1 to 4 minutes. This is exercise where a lot of acid builds up in the muscle. There was no difference in short efforts finished within 1 minute or in repeated short all-out sprints.
Tingling, or 'paresthesia'
Caused by skin nerves reacting
Taking a large amount of beta-alanine at once makes the face, neck and backs of the hands tingle; this is called 'paresthesia'. It happens because sensory nerves that run to the skin react to beta-alanine. It usually goes away within 1 to 1 and a half hours, and no harm from it has been reported.
Common misconception
Does it have to tingle to work?
The tingling is just skin nerves reacting to a large single dose. The effect comes from the carnosine built up in muscle over several weeks. In fact, a slow-release product caused no more tingling than a fake powder, yet it still raised muscle carnosine.
Summary
The raw material for carnosine, which soaks up muscle acid
Beta-alanine is an amino acid used to make carnosine in muscle, and carnosine soaks up the acid made in muscle during very hard exercise. The tingling is not a sign that it is working; it is a reaction of skin nerves. Related terms: carnosine, creatine, amino acids