L-lysine, or simply lysine, is one of the building blocks of protein and is essential for maintaining a healthy body and keeping systems functioning at an optimal level. Lysine helps the body repair itself, and deficiency can lead to fatigue, hair loss, muscle soreness, and a decreased immune system. Increasing one's lysine consumption through diet or supplements can help improve the symptoms of severe chronic conditions.
The herpes simplex-1 virus (HSV-1) causes cold sores, chronic fluid-filled blisters that develop on and around the lips and tongue. The amino acid arginine encourages the flare-up of HSV-1 and subsequent breakouts. Lysine can combat this effect of arginine. Topically applying creams containing lysine to the lips when cold sore symptoms first appear can help minimize the blister. Furthermore, supplementing the diet with lysine may keep the balance between these two amino acids in check, reducing the occurrence of cold sores. Foods that are high in lysine and low in arginine, such as fish, meats, and dairy, are recommended to prevent outbreaks of HSV-1.
Collagen is an essential compound responsible for building cartilage, bones, and connective tissue. Lysine helps in the formation of cartilage and collagen, while also preventing the breakdown and excretion of collagen during digestion. Calcium and collagen function in conjunction with each other to prevent bone loss. In a diet low in lysine, the formation of calcium and collagen slows. This is one reason why many people with lysine deficiencies have fragile bones.
Some studies suggest that lysine may help treat clinical anxiety and disorders such as schizophrenia. Especially in the latter, lysine may reduce severe anxiety-like symptoms when added as a supplement to conventional therapy. Based on research studies, it appears that lysine works by lowering the stress hormone cortisol and can be used either alone or in combination with the amino acid arginine. Lysine also shows potential to improve digestive problems triggered by stress, such as diarrhea associated with irritable bowel syndrome (IBS).
Certain compounds in the body called advanced glycation end products (AGEs) are created when protein or fat combine with sugar in the blood. When in excess, they exacerbate cell aging and deterioration, and people with diabetes have a higher concentration of AGEs. Scientists speculate that higher blood sugar levels may encourage the formation of these proteins, which are implicated in many diabetes-related complications such as nerve, eye, kidney, and heart diseases. Researchers are studying therapies that aim to stop AGEs from collecting in large numbers. Lysine may help reduce the formation of AGEs, thereby reducing the risk of diabetes complications.
In addition to decreasing AGEs, lysine can lower fasting blood glucose levels and reduce inflammation of the pancreas, both of which help people with diabetes manage blood sugar levels. Controlling blood sugar to avoid peaks and valleys allows better symptom management. Although more research is needed, some studies show lysine can increase insulin concentration and secretion; the intake of a lysine-glucose mixture led to more insulin than the absorption of glucose alone.
Lysine can influence the levels of LDL (low density) cholesterol in the bloodstream. LDL cholesterol accumulates around the arteries, leading to hardened artery walls and reduced blood flow. A diet rich in lysine inhibits the build-up of LDL cholesterol and keeps the cardiovascular system working properly. Plaque build-up in the arteries can increase one's risk of heart disease, stroke, and erectile dysfunction. Furthermore, the anti-inflammatory properties of lysine reduce high blood pressure and help manage hypertension.
Calcium helps build strong bones, but a healthy amount of lysine can improve absorption and reduce the amount of calcium excreted during digestion, helping bones use calcium and other minerals more efficiently. This is particularly important for older women to reduce the risk of osteoporosis.
Some studies into natural cancer treatments show lysine has a rebuilding effect on damaged DNA, which can lead to cancerous growths. Lysine helps repair damaged parts of the cells, reducing the likelihood of the cells becoming cancerous. Furthermore, lysine can help chemotherapy act more efficiently, with fewer harmful side effects. Preliminary studies conducted in animal models even suggest lysine could help kill cancerous growths.
The anti-inflammatory properties of lysine are especially helpful in regulating the digestive system and reducing the effects of leaky gut, characterized by an increased intestinal permeability; it is a digestive condition in which bacteria and food particles "leak" through the intestinal wall. This causes food sensitivities, low energy, joint pain, autoimmune diseases, and thyroid disease. A specific form of lysine, poly-L-lysine, has specific anti-inflammatory effects on the lining of the stomach and intestines. Regular consumption can ease the inflammation from leaky gut and other conditions such as IBS.
Many foods are rich in L-lysine. Lean beef, fish, and lamb are especially good sources, and turkey and chicken are fairly high in this amino acid, as well. Parmesan cheese, white beans, and eggs are excellent vegetarian options for lysine, critical for vegetarians who have a harder time acquiring all types of amino acids from the diet.
Many types of meat are high in l-lysine. Beef, chicken, and pork are particularly good choices when trying to increase intake because they are also good sources of other amino acids that are not produced naturally in the body, such as leucine, methionine, and tryptophan. There are health drawbacks to eating large amounts of red meat, however. Emphasize poultry in most meals, and eat red meat only occasionally to get the benefits of l-lysine without the potential drawbacks.
Tuna, salmon, and many other fish are rich in l-lysine. In addition to providing this important amino acid, fish offer a range of nutritional benefits. Regular consumption of fish ensures people are getting enough omega-3 fatty acids and may reduce the risk of arrhythmias, strokes, heart attacks, and help stave off the mental decline that is a common part of the aging process.
Getting enough l-lysine can be a challenge for those who don't eat meat. Ricotta cheese is a good alternative, with 80 percent of the recommended daily intake in a 1/2 cup serving. Research has shown that the fat in dairy products does not have the same impact on the cardiovascular system as that of meat. Even full-fat dairy products seem to reduce, rather than raise, the risk of heart disease. In addition to being an excellent source of l-lysine, ricotta is also a good source of protein.
Green peas are another good source of l-lysine for those who don't eat meat. At 24 percent of the recommended daily intake for this amino acid, green peas are not as high on the list as some other options, but still provide plenty of l-lysine, as well as other health benefits. They offer a balance of vitamins and minerals and are a good source of fiber.
Tempeh and tofu, along with many other soy products, are excellent plant sources of l-lysine. Firm tofu has 106 percent of the reference daily intake of l-lysine. Even snacking on a handful of roasted soybeans can add up to 35 percent of the RDI of this amino acid. Along with l-lysine, soy products are a good source of protein, calcium, and fiber. Anyone eating a plant-based diet should consider using these products to consume important nutrients. For those who eat meat, adding tofu and tempeh to the diet offers an easy and inexpensive way to increase protein while lowering saturated fats.
This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other healthcare professional.