L-Cysteines

Cysteines are amino acids produced naturally by the body, but some people can further benefit from additional cysteine sources, such as through supplements and food. It is essential to promote good health, but it is classified as "non-essential" and derives from methionine, which is an essential amino acid. Its role in the structure of the protein within the body is to crosslink proteins to increase their rigidity and resistance. In general, cysteines enhance the body's ability to create antioxidants. It produces the antioxidant fluticasone and the amino acid taurine in addition to helping immune system cells communicate.

Cysteines are the only amino acid capable of forming covalent bonds, which means they share an electron between atoms . This distinction allows the protein to bend and fold, which contributes to granting it the traits that are taken advantage of in the food industry. This trait is also why it is considered the first base for many important structural proteins in connective tissue. One of the other nutrients it can convert to is taurine, which aids the nervous, digestive, and vascular systems. Almost every amino acid occurs in two different isomeric forms — depending on whether it is a left- or right-handed configuration — so naturally, there are two different variants of cysteines.

L-cysteine is a common food additive. D-cysteine, on the other hand, is not an additive in food or flavoring agents. It is more common in bacteria, but it can still maintain a presence in trace amounts within processed foods. The two kinds of cysteines are mirror images of one another. However, most living organisms keep their cysteines configured to the L-cysteine format, n-acetylcysteine. Once that organism dies, the body can no longer keep their cysteines configured accordingly, and it converts to the D-cysteine version. This conversion is a process called racemization .

Manufacturers collect these natural and abundant protein resources and dissolve them in hydrochloric acid. L-cysteine is then isolated through chemical processes that separate the compound, which is then shipped to producers of processed foods.

Some methods forego using anything derived from the human body. For instance, certain food and nutrition laboratory services have developed formulation solutions that directly synthesize cysteines. Cysteine synthesizes from serine, which synthesizes from phosphoglycerates that form during glycolysis. In addition, one natural production method for natural L-cysteine is Wacker Chemie 's fermentation in a production fermenter. With this process, a microorganism strain is cultured in a fermentation medium. The L-cysteine is controlled in a targeted way by an iron concentration. Completing this process chemically instead of using human bi-products may mean a bit slower of a manufacturing cycle, but it omits the need to use products that might make some consumers uneasy. It has been reported by the Vegetarian Resource Group that only 10 percent of products that incorporate this amino acid use the synthetic approach. Finding reputable manufacturers that use this strategy makes it possible for vegans, vegetarians, and others to take advantage of the benefits of L-cysteine by using a synthetic version. Thankfully, the FDA requires that the use of L-cysteine be labeled , and it is usually preceded by "dough conditioner" or referred to as "E920." The only circumstance that means companies can omit the inclusion of L-cysteine is when it is considered a "reaction flavor," which entails heating a protein source combined with sugar to create a mixture of chemicals that produce specific flavors. Using this process can enhance flavors, particularly in meat, when they are undergoing a particular reaction.

As discussed, common applications for L-cysteine are as a dough conditioner and preservative , among other uses. However, it also delivers many health perks to those who take supplements or eat diets rich in it. A variety of different people can benefit from diets filled with L-cysteine, including:

• Infants — through their mother's breast milk — to promote body growth
• Men wishing to start families by increasing fertility
• Elderly adults — through diet and supplementation —by improving vascular health, immune system, cognitive function, inflammation, and more
• Psychiatric patients by lessening symptoms of illnesses, such as obsessive-compulsive disorder and bipolar disorder
• Patients suffering from chronic diseases, including cataracts and arthritis
• Nightlife enthusiasts by dampening the severity of hangovers

This non-essential amino acid has numerous benefits to a large pool of people because the digestive system is notorious for compromising some of the absorptions of nutrients and is not the most optimized function in your body. This fact is particularly true to those who are in a weakened state, such as individuals with medical issues, older adults, young children, and those who may have consumed too much alcohol the night before.

Despite the numerous benefits L-cysteine poses to consumers, it is commonly used to extend the shelf life of the foods you most commonly use. Another typical use is as a dough conditioner and strengthener that makes it possible for pizza and bakery crust to stretch out, becoming the perfect surface for several ingredients. The most common application by far for L-cysteine, however, is in the aforementioned development of savory flavors via reaction flavors.

Other industries use L-cysteine as well. It is used for pharmaceutical purposes in medicine and hospitals as well as personal care products to achieve a longer shelf life. Hairdressers and barbers also put them to good use to create a certain hairstyle, such as a perm. Keratin — the main structural element in hair that is often applied as a supplement to keep locks healthy — improves through the addition of cysteine, which breaks up disulfide bonds and grants your hair greater elasticity and strength.

Some foods are naturally high in L-cysteine and do not have to undergo any chemical processes. To incorporate these natural sources of L-cysteine in combination with other important amino acids, make sure you are eating enough of the following foods in conjunction with other healthy choices to ensure a well-rounded diet. These foods high in L-cysteine cover a multitude of different food groups and preferences, so you can likely take advantage of their benefits while finding something you actually enjoy consuming.

• Soy: Soy products, such as roasted soybeans and tofu, contain up to 638 mg of cysteine, which is more than double the regular daily intake of the amino acid. Consuming soy is an outstanding way to increase your intake of plant protein, which has cardiovascular functions like lowering blood pressure . Soy-based foods also do not contain cholesterol and are very low in saturated fats.
• Beef and lamb: Cuts of meat like beef and lamb contain up to 460 mg of cysteine, which puts you well over the recommended daily intake. These meats are also an excellent source of many other vitamins and minerals , such as iron, B12, and zinc. Because of these added nutrients and being a rich source of protein, beef and lamb promote the growth and performance of muscles in the body.
• Nuts and seeds: Similarly to beef and lamb, most nuts and seeds will get you well over your recommended daily intake of cysteines at around 451 mg. The best seeds for upping your cysteine intake include watermelon, sesame, flax, pumpkin, and chia seeds. The best nuts consist of pistachios, brazil nuts, and pine nuts.
• Chicken and turkey: These meats do not quite contain the recommended daily intake of beef and lamb, but they are still a good source, containing 423 mg. Chicken generally includes a bit more than turkey, but both are great sources of cysteine and other vital minerals, such as vitamin B12. Overall, these foods can help combat several health issues , including obesity, cardiovascular disease, Type 2 diabetes, cancer, and more.
• Oats: Oat and rice bran, wheat germ, and oatmeal are all good sources of cysteine (408 mg RDI). This group of foods contains a lot of soluble fiber that aids digestion and contributes to lowering cholesterol. Oat products are also abundant in protein, iron, calcium, zinc, magnesium, and other quality nutrients.
• Pork: Pork tenderloins are another excellent source of cysteine, containing 388 mg. Other pork-based foods — such as bacon, ham, pork chops, roasts, and ribs — are above the RDI and are not bad choices either. The abundance of amino acids and other vitamins and minerals make it a quality food choice.
• Fish: If you are a fan of the sea, you can turn to fish and shellfish to get your recommended daily intake of cysteine without a problem. Include seafood catches like tuna, mussels, salmon, shrimp, and other nutrient-rich fish in your regular diet. In general, fish are some of the healthiest sources of food on the planet and are a great source of vitamin D.
• Dairy: Dairy products, such as cheeses, eggs, yogurt, and milk, are all quality sources of cysteine. Cysteine is most prevalent in swiss cheese, but natural yogurts and other cheeses like parmesan are the next best things. In general, dairy choices should make you reach your recommended daily intake.
• Legumes: Legumes are certain plants that are high in cysteine and include chickpeas, kidney beans, and lentils. This source is inferior to most others on this list, but legumes are still a good option to shake things up. In addition to amino acid prevalence, they are high in B-group vitamins and are particularly helpful for woman around child-bearing age .
• Whole grains: Pairing cysteine-rich meats such as beef, lamb, chicken, and turkey with a whole grain option such as wild rice, couscous, or quinoa will really help you reach your recommended levels and have a nutrient-dense meal. These foods are vastly superior to plain white rice and other less healthy options. Making the switch to whole grain alternatives is a positive step in reaching the level of health you are looking for.

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