The Importance Of Lysine + The Top High-Lysine Foods To Eat

Lysine is an important micronutrient with many health benefits. But how can you be sure you're getting enough of this essential amino acid in your diet? To find out, we spoke with nutrition experts who share the best sources of lysine, the benefits of eating lysine-rich foods, how to get enough as a vegetarian, and more.

If you remember back to high school biology class, amino acids are the building blocks of protein—one of the three macronutrients in the human diet, along with carbohydrates and fats.

Both plant and animal proteins are made up of 20 amino acids1. The human body needs all of them to produce the proteins required for optimal health.

Eleven of these amino acids are "nonessential" and are produced in sufficient quantities by your body. The remaining nine are "essential," meaning they must be acquired through diet since your body doesn't produce adequate amounts.

Among the essential amino acids are lysine and the branched-chain amino acids (BCAAs) leucine, isoleucine, and valine. BCAAs are well-researched and championed nutrients by the fitness community for their role in muscle protein synthesis (MPS)2 and recovery3.

"The building and repair of tissue proteins is termed protein synthesis," Eric Williamson, Ph.D., R.D., a registered dietitian, exercise nutrition expert, and founder of Unlocked Fitness and Nutrition, tells mindbodygreen. "This process allows our body to replace damaged or dysfunctional organ tissues. It's also important to build muscle proteins in response to exercise for gains in muscle mass, strength, speed, and endurance."

"As soon as you turn on protein synthesis, then you need all 20 [amino acids]," Don Layman, Ph.D., a leading amino acid researcher at the University of Illinois at Urbana-Champaign, previously explained on the mindbodygreen podcast.

Clearly, each of the 20 amino acids has unique properties, benefits, and roles. Like all other amino acids, lysine is essential for healthy growth, development, and functioning4. In addition, lysine is crucial for producing carnitine5, a vital compound in energy production that converts fat into energy.

An older study from 20076 found that most healthy adults require around 14 milligrams (mg) of lysine per pound (30 milligrams per kilogram) of body weight daily.

For a 160-pound person, this equates to 2,240 mg (2.24 grams) of lysine per day. Another study7 suggested that the optimal lysine concentration for adults is 45 mg per gram of protein intake, the second highest amino acid concentration behind leucine.

Lysine is an essential nutrient that offers several health benefits, including:

Lysine helps your body absorb calcium8, which is vital for strong, healthy bones. Also, lysine aids in the formation of collagen, a protein critical for bones and connective tissues.

In a recent human-based study9, certain essential amino acids, including lysine, were associated with decreased bone loss that naturally occurs from aging.

Lysine helps produce various hormones, enzymes, and antibodies to support the immune system. In addition, it offers antiviral properties that may protect against the herpes simplex virus, with some research10 indicating it improves nutrient balance in the body to inhibit the spreading of the virus.

Lysine plays a pivotal role in skeletal muscle growth by increasing protein uptake in muscles and MPS, according to one animal study11. 

Research12 shows that lysine is typically lower in plant-based proteins than animal-based ones. That's because most animal proteins are complete proteins (contain sufficient amounts of all nine essential amino acids), while many plant proteins lack some amino acids.

But that doesn't mean vegetarians and vegans can't get adequate lysine in their diet.

Strategically pairing plant-based proteins13 that complement one another's amino acid profiles to form complete proteins can help ensure you get enough of each essential amino acid, including lysine.

Additionally, supplementing with a high-quality vegan protein powder can help you meet your daily lysine intake.

"Vegans and vegetarians can obtain adequate lysine for protein synthesis by ensuring they pair low-lysine plant proteins with high-lysine foods in the same meal," explains Williamson. "For example, the lack of lysine in rice can be made up for by consuming lentils, which have a high lysine content."

If you need some inspiration for getting more lysine in your diet, consider trying the following sample meal plan:

Lysine is an essential amino acid required for proper growth, bodily functions, and energy production. It can also support bone health, boost the immune system, and promote muscle growth.

While lysine is typically found in animal proteins, plant-based eaters can get enough by combining high-lysine plant-based foods with other plant proteins. This will help ensure the consumption of complete protein sources and meet daily lysine requirements without any extra effort.

Whether you're a meat eater or vegan, meeting your daily protein needs with healthy protein sources will go a long way in ensuring that you're not low in lysine.