Diet

Leucine

introduction

Leucine is an essential amino acid that the body cannot make itself. Leucine must therefore be taken in through food. Leucine is also one of the three branched chain amino acids (BCAA = branched chain amino acids). Due to the special structure of leucine, it differs significantly from the other amino acids in terms of its function and effect. In recent years, leucine, together with the other two branched-chain amino acids valine and isoleucine, has come more and more into focus, as it has positive effects on muscles and fat burning not only in weight training.

Read more on the topic: Amino acids and exercise

Function and effect

Leucine fulfills many important functions and tasks in the body. It owes its diverse effects to its special structure and the cooperation with the other two BCAA's valine and isoleucine. The effects of leucine include:

Energy supply of the cells (especially in the muscles and the liver)
Promotion of fat metabolism
Preventing muscle breakdown
positive effect on the growth hormone somatotropin: the hormone promotes height growth especially in childhood and adolescence, but also has other positive effects on muscles and bones, for example. Somatotropin also plays an important role in stressful situations or with increased stress
Promotion of wound healing, as leucine is involved in the development of new tissue
Regulation of the insulin balance: Leucine stimulates the release of insulin from the pancreas, which controls the blood sugar level and at the same time reduces the release of the stress hormone cortisol
Building block of glutamic acid

Overall, leucine is involved in many important processes that take place in the body, which is why the amino acid is not only interesting for athletes but also for other groups of people such as diabetics, obesity patients, people with liver diseases and others.

Read more on the topic: Supplements for building muscle

Leucine as a Dietary Supplement - Who Is It For?

In order for leucine to have a therapeutic effect as a dietary supplement, a daily intake of at least 1000mg is necessary. Thanks to its special properties, leucine can have positive effects on a variety of complaints and clinical pictures as well as on muscle building and endurance sports. For the following groups of people, leucine can therefore be regarded as useful as a supplement:

diabetes
athlete
Obesity patients to assist with diet
depressions
States of exhaustion
Muscle breakdown

Overall, the individual leucine requirement and the question of whether supplementation is necessary must always be decided on a case-by-case basis and preferably with the involvement of a doctor.

Read more on the topic: Lose weight with amino acids

For muscle building

Leucine is used by many athletes in the area of muscle building. Due to its special properties, the amino acid has a positive influence on protein biosynthesis and thus prevents, for example, the breakdown of proteins in the body after physical exertion, which leads to the maintenance of the muscles and an increased protein balance as a result. Leucine is one of the ketogenic amino acids, which means that a ketone body is formed when the amino acid is broken down. In contrast, the non-ketogenic amino acids are involved in the formation of new glucose. Leucine inhibits the breakdown of glucose in the body during training and thus has positive effects on the body's own energy production, so that with sufficient leucine intake, a sustainable increase in performance is the result.

Through this mechanism of action, leucine also prevents the release of other amino acids that would otherwise be used for gluconeogenesis, the formation of new glucose and thus for energy production. Through this effect, leucine prevents muscle catabolism, the breakdown of muscle mass.

Another effect of leucine is the stimulation of insulin secretion. If the body's own leucine concentration increases, the pancreas secretes insulin in larger quantities. Among other things, insulin is used by the body to transport amino acids and glucose into the body's cells. Leucine then gives the muscle cells in particular more amino acids for building muscle. At the same time, leucine also has an effect on cortisol levels. This is lowered by the amino acid, which also counteracts muscle breakdown.

As already mentioned, leucine also has an influence on the release of growth hormones. In childhood and adolescence, these primarily ensure length and bone growth; in adulthood, however, they promote muscle growth, as they have a positive effect on the relationship between muscle tissue and fat cells.

Because of this, leucine is particularly suitable during a diet or definition phase. The amino acid has been shown to increase the basal metabolic rate.

In summary, leucine plays a special role in building muscle, as it not only maintains muscle mass, but also provides more energy for training and increases performance.

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When should it be taken?

When supplementing with leucine, the time of intake also plays a special role. This is especially the case when leucine is used as a dietary supplement in sports. With the mode of action of leucine in mind, it makes sense that leucine should be taken before exercise. The reason for this is the preservation of glucose and amino acid stores, which are quickly emptied when exercising. Conversely, the more carbohydrate-rich food is consumed before training, the lower the leucine dose required. As a guideline, 5-10g leucine can be given before intensive training units.

To promote anabolism, another 5-10g of leucine can be taken after the workout. According to various studies, dividing the leucine dose over the day does not lead to the desired success.

Read about this too: Dosage and intake of BCAA

dosage

The dosage of leucine depends on the intended use of the amino acid. Since leucine is an essential amino acid, certain amounts have to be ingested through food every day. Normally, the body needs around 1.2 kg of leucine per day. This results in the following dosing options when leucine is used as a supplement:

Training-free days: 1g leucine
Training days: 2-3g leucine
with very intensive training or increased stress: max. 10g as a single dose (guideline value 0.1g / kg body weight)

Basically, at the beginning of a supplementation with leucine, the full dose should not be taken directly, but the body slowly gets used to the additional administration of leucine. The purpose is to avoid possible side effects such as gastrointestinal problems.

In order to strengthen and support the effect of leucine, it is recommended to combine it with other supplements. In addition to the other BCAA's, this also includes vitamin B6 and creatine.

Side effects

Side effects when using amino acids such as leucine are very rare. This is because the amino acids are substances that the body needs anyway. However, there are a few things to consider before taking leucine to avoid potential side effects:

Drug interactions. Under certain circumstances, the simultaneous administration of leucine and drugs can reduce or increase their effect (for example, when taken at the same time with insulin, levodopa or glimepriden)
Leucine should be crept in, which means slowly increasing the dose so that the body can better adjust to it
For people with a sensitive gastrointestinal tract, it is advisable to give leucine after meals
Some circumstances are contraindications to the consumption of leucine. These include, for example, hypersensitivity, an existing pregnancy or liver dysfunction

Basically, before taking it, it should always be clarified which dosage is appropriate and whether the general state of health and age allow supplementation.

Read more on the topic: BCAA - side effects

What is the difference between leucine and isoleucine?

On a chemical level, leucine and isoleucine are very similar. The two amino acids are isomers. This means that they have the same molecular formula, but differ in the structure of the molecule. This difference leads to some different properties of the two amino acids. Isoleucine, for example, is used for gluconeogenesis, which is the formation of new glucose. It is also an integral part of human medicine as part of an amino acid infusion solution for parenteral nutrition. Leucine and isoleucine together are two of the three amino acids that are commonly grouped together as BCAA's and are often taken in combination with the 3rd amino acid (valine). The desired synergetic effects of BCAA's include, for example:

Regulation of the hormonal balance
Increase in performance
Improve concentration
Increase in the rate of protein synthesis

Read more on the topic: Areas of application of BCAA

Foods with leucine

Leucine is found in large quantities in many foods. Below are some foods with the respective amount of leucine per 100g:

Millet 1350mg
Spelled flour 1023mg
Wheat flour 860mg
Soybeans 2840mg
Peas 2340
Kale 250mg
Potato 140mg
Strawberry 44mg
Avocado 197mg
Peanuts 2030mg
Cashew nuts 1440mg
Parmesan 3500mg
Camembert 2250mg
Buttermilk 350mg
Chicken Egg 1260mg
Beef liver 1990mg
Lamb 1690mg
Tuna 2170mg
Sardine 1870mg
Trout 1770mg

Products

In addition to many foods, leucine can of course also be supplemented directly. There are various forms of administration of the amino acid: powder, capsules and tablets.

Leucine powder: Leucine powder is available as a pure monopreparation or in the popular combination with valine and isoleucine, the other two branched-chain amino acids. The advantages of the powder are that it is easy to dose and can be stirred into food and drinks. In terms of price, too, the leucine powder is usually much cheaper than other forms of administration. One disadvantage, however, is that it is impractical to take with you on the go.
Leucine capsules or tablets: In capsule or tablet form, the great advantage is that the desired dose can be easily taken on the go. This form of administration is therefore very easy to handle and avoids any inherent taste of the powder. Capsules and tablets already have a predetermined dose, so they are not as individually adaptable as leucine powder. The capsules / tablets can also be a problem for people with swallowing difficulties or children. Due to the special production method, they are usually significantly more expensive than the leucine powder.

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