Lysine
Lysine is one of the nine essential amino acids and the limiting amino acid in most grain-based diets. It is critical for collagen synthesis, calcium absorption, and the production of carnitine, the molecule that shuttles fat into your mitochondria for energy.
Why It Matters
If you eat mostly rice, wheat, or oats, lysine is the amino acid you are most likely to fall short on. That is why traditional food pairings (rice with beans, hummus with pita) exist: legumes are lysine-rich and balance the deficit. For lifters, lysine matters because it is required to make carnitine, build collagen for tendons and ligaments, and support proper immune function.
Pea protein is unusually high in lysine for a plant source, which is one reason it became the go-to vegan powder. Rice protein on its own is low in lysine, which is why most premium vegan blends pair pea and rice together.
How to Spot It on a Label
Lysine is listed on the amino acid panel of any quality whey or vegan tub. Whey isolates deliver around 2.5g lysine per 25g protein. Pea isolate is similar. Pure rice protein typically lists below 1.5g, which is why blended formulas exist.
Examples from real products
Related Terms
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