‘I’m an RD, and Here’s How To Eat More Lysine, an Amino Acid That Boosts Your Mood and Immunity' (2024)

The cold, flu, and cold sore season is upon us, which means it’s time to fill your refrigerator with foods that will help keep both your immune system and your mood up. Enter lysine, a component of protein that has been proven to improve health in a multitude of ways. Here we’ll learn about the key ways that lysine benefits your body and where you can find it naturally in foods.

What is lysine?

Lysine is an essential amino acid, or building block of protein in our bodies. There are 20 known amino acids and of those, there are nine that cannot be created by the body and must be consumed. These are considered to be essential amino acids. Interestingly, our bodies don’t store excess amino acids, so it’s crucial that we consume them every day through foods. Without amino acids, your body start to break down muscle tissues to extract the amino acids it needs to carry out vital functions.

Health benefits of lysine

Beyond being a vital building block of protein, lysine has so many unique health benefits. At the cellular level, lysine is essential in carnitine production. Carnitine is a nutrient that converts fatty acids into energy and also helps to lower cholesterol.

Lysine can also aid in the absorption of calcium in the body, helping to prevent osteoporosis. Plus, it helps to form collagen, supporting all the connective tissues in the body, like muscle, tendons, and ligaments, while speeding up wound healing.

Lysine has also been found to be effective in reducing anxiety and cortisol levels. Cortisol is our main stress-hormone and circulation of excess cortisol in the body can have cascading effects, from slowed metabolism to reduced immune system function.

One of the more notable benefits of lysine is its effect on herpes simplex virus (HSV)—both types 1 and 2, otherwise known as cold sores or genital herpes. One study found that lysine consumption of over three grams per day improved participants’ recovery time during a flare. The herpes virus feeds on arginine, another amino acid, and lysine is an antimetabolite of arginine. This means that with increased lysine intake, arginine-fueled viral growth is limited. Those who are wanting to take hold of their HSV symptoms through diet should focus on both increasing sources of lysine in their diet while limiting sources of arginine as much as possible. Arginine is essential for viral replication of any kind throughout the body, so these benefits span to all viruses. Plus, lysine helps produce vital hormones and other immune cells like antibodies.

Translation? Lysine is a big player in your overall immune health, and it's a key part of maintaining your mental health and mood, too. Bonus lysine benefits include potential for improved blood sugar and blood pressure control.

8 lysine foods to stock up on

Most people don’t get enough lysine in their diet. Because it’s an essential amino acid, symptoms associated with deficiency can include fatigue, anemia, nausea, dizziness, decreased appetite, agitation, and slowed growth and healing. The daily recommended intake for lysine is generally somewhere between 2,000 and 3,000 mg per day but a good rule of thumb is to shoot for at least 1,000 mg every day. Here are some of the best food sources to help you get your daily dose.

1. Chicken

Chicken is not only a great source of lean protein, but it really delivers when it comes to lysine. A mere three ounces of boneless, skinless chicken breast provides 2,621 mg of lysine. As if you needed another reason to make chicken tikka masala this weekend…

2. Tofu

A tasty plant-based protein, tofu is an incredible vegan option for meeting your daily lysine needs. One cup of firm tofu contains 2,225 mg of lysine, giving meat a real run for its money.

3. Seafood

Oysters, shrimp, tuna, and even king crab are all packed with lysine. Just one king crab leg will pretty much knock out your lysine needs for the day, containing a whopping 2,257 mg of lysine, while three ounces of tuna offers an equally impressive 2,335 mg.

4. Spirulina

If you haven’t yet heard of this buzzworthy superfood, spirulina is a kind of blue-green algae that flourishes in both fresh and saltwater. It is absolutely packed with antioxidants and nutrients, including lysine. Just two tablespoons provides 420 mg of lysine.

5. Dairy products

While many have written off dairy for one reason or another, there’s no arguing that these products contain many of the different amino acids, including lysine. An eight ounce glass of milk boasts 691 mg of lysine, low-fat ricotta cheese provides a noteworthy 1,678 mg per half cup, and cream cheese offers 2,859 mg per two ounces.

6. Legumes

Legumes are great meatless protein options that also provide a hefty dose of fiber and micronutrients. They also contain amounts of lysine that will help you meet your daily goals. For example, per cup, canned navy beans contain 1,381 mg, green peas have 502 mg, and lentils have about 1,300 mg.

7. Eggs

With 452 mg of lysine per one large egg, these conveniently-packaged protein bombs are great sources of lysine. There is lysine in both the yolk and the white, so to get the most bang for your buck, spring for the whole egg—duh.

8. Quinoa

Beyond being an incredible source of fiber and antioxidants that can help protect against chronic illness like heart disease and type 2 diabetes, quinoa also delivers in the lysine department. One cup gets you 452 mg closer to your daily needs.

Whether it be to soften anxiety, boost your immune system, or speed recovery from a cold sore, lysine is a great addition to your diet for so many reasons. These foods can help you meet your lysine goals both seamlessly and deliciously.