Lysine acts as a building block for proteins found in muscles, connective tissues and enzymes, and it’s needed for the production of some hormones. A serious lack of lysine can contribute to making you feel a bit anxious or blue, although deficiency is not common because many foods contain this amino acid. Since mood is dependent on many factors, adding lysine to your diet is no guarantee of happiness. Consult your doctor if you experience chronic depression.
Lysine is probably best known for building muscle fibers and collagen, the elastic-like compound in your skin. Lysine is a supplement commonly taken by bodybuilders and other athletes who want to look stacked and improve their strength. Lysine is also sometimes taken to combat the herpes virus because it inhibits viral growth.
Lysine and Serotonin
Lysine affects serotonin, a neurotransmitter and the main “feel good” hormone within your brain. The control of serotonin in your brain is the primary action of most antidepressant medications. In addition to mood, serotonin is also involved in regulating appetite, sleep, memory and learning. Lysine works to reduce the impact of stress and related feelings of anxiety and depression. A chronic dietary deficiency of lysine can lead to mood imbalance as well as poor appetite, insomnia, fatigue and faulty short-term memory.
Animal-based foods such as beef, poultry, fish and dairy products are the richest sources of lysine and are also the most digestible. Lysine is found in many veggies, but it’s not as easily metabolized and absorbed by your body when you obtain it from those sources, which is why vegetarians are most at risk of deficiency. The best vegetarian sources of lysine include spinach, kale, alfalfa, wheatgrass, cauliflower, celery, soy products, kidney beans, green beans, lentils, pears, papayas, apricots, bananas, almonds and cashews.
Mood imbalance and depression have a variety of causes, so you shouldn’t assume that a lack of lysine is the prime suspect. Many other dietary deficiencies and hormone issues affect the brain and trigger depression, so talk to your doctor or a mental health professional to properly understand and diagnose your condition. Supplementing with lysine is safe and causes no side effects up to about 1,500 milligrams daily. If you take more than that in a day, you may suffer from nausea, diarrhea and increased blood cholesterol levels. More research is needed before lysine supplements can be recommended to treat stress-related mood problems such as anxiety or depression.
- Compendium of Pharmaceuticals and Specialties; Canadian Pharmacists Association
- Human Biochemistry; Charles Dreiling
- Encyclopedia of Human Nutrition; Benjamin Caballero et al.
- PDR for Nutritional Supplements; Sheldon Hendler and David Rorvik
Sirah Dubois is currently a PhD student in food science after having completed her master's degree in nutrition at the University of Alberta. She has worked in private practice as a dietitian in Edmonton, Canada and her nutrition-related articles have appeared in The Edmonton Journal newspaper.