Essential amino acid
Lysine
The one plant-based eaters actually need to watch.
30 mg/kg/dayAbout 2.10 g a day at 70 kg
What it builds
Lysine is structural. It is a required input for collagen (working alongside proline), which means connective tissue, skin, tendon and bone matrix. It is also the raw material for carnitine, the molecule that ferries fatty acids into your mitochondria to be burned, and it plays a direct role in calcium absorption and in antibody structure.
Nothing on that list is exotic. That is rather the point: lysine is used everywhere, constantly, and unlike the glamorous amino acids it has no supplement industry talking about it.
Where lysine actually comes from
Animal foods are uniformly rich. Among plants, legumes are the heavyweights and grains are the weak spot, which is the entire reason the classic pairings exist.
Ranked by a realistic portion rather than per 100 g, because nobody eats 100 g of pumpkin seeds. Figures are digestibility-adjusted, so these are the amounts the app credits you with, not the amounts printed on the packet. Computed live from the 72 foods in the AminoLens recommender pool.
All foods
Every food in the pool, animal and plant.
| Food | Portion | Per portion |
|---|---|---|
| Chicken breast | 120 g breast | 3.01 g |
| Beef (eye of round) | 120 g | 2.85 g |
| Lamb leg | 120 g | 2.84 g |
| Pork tenderloin | 120 g | 2.77 g |
| Chicken thigh | 120 g | 2.67 g |
| Turkey breast | 120 g | 2.53 g |
Plant-based only
Vegan foods only. The list most people actually need.
| Food | Portion | Per portion |
|---|---|---|
| Soybeans | 120 g cooked | 1.21 g |
| Tempeh | 100 g | 826 mg |
| White beans | 150 g cooked | 822 mg |
| Lentils | 150 g cooked (1 cup) | 775 mg |
| Pinto beans | 150 g cooked | 775 mg |
| Black beans | 150 g cooked | 748 mg |
Signs you might be short
Outright lysine deficiency is not something that happens to people eating enough food in a developed country. Do not let a content farm convince you otherwise.
The realistic case is duller and far more common: a grain-centric plant-based day. Porridge, a sandwich, pasta, rice. Every one of those is lysine-poor, and a day built from them very often shows lysine as the limiting line in AminoLens, however respectable the protein total looks.
Pairs well with
Grains. Rice and beans, hummus and pita, dal and rice, beans on toast. Grains are low in lysine and decent in the sulphur amino acids; legumes are the exact mirror. Traditional cuisines solved this centuries before anyone had a word for it.
See your lysine coverage
Photograph a meal and watch where the protein actually goes.
Analyse a meal