Lysine as the 1st Limiting amino acid in cereals

Many people around the world consume cereal-based diets, either for economic, religious or ethical reasons. In most cases such diets, supplemented with vegetables and legumes, are sufficient to provide essential amino acids needed by our bodies for grow and/or sustenance. In some cases, though, one or several essential amino acids can be severally limited. Most notable case is lysine, which is by far the most limiting amino acid in cereal diets.

Fortification with lysine to improve the protein value of diets have been supported well through several intervention trials conducted in developing regions. Among others, see:


While the WHO/FAO recommendations call for at least 39 mg of lysine per person per day, some poor populations eat diets that do not reach such levels. It is therefore not a major surprise that even short (3-month-long) fortifications with lysine triggered some substantial improvements in growth of children, immune parameters and overall nutritional status of the tested populations. Adding lysine alone diminished the overall protein deficiency by as much as 50% - making it an effective and very affordable way to tackle protein intake issues.

Of course, the improvement of dietary quality must be the long-term aim with several approaches. Over the last several decades, increases have occurred in the availability of food energy and total protein even in developing countries. However, for the very poorest developing countries over the same period, changes have been almost nonexistent, and the values for some nutritional indicators have even declined due to political unrest. This adds to the significance of reaching out to affected populations, especially growing children, with immediate and effective solutions in a form of fortifications.

In the case of lysine, the issue is further strengthened by the indications that the lysine benefits go far beyond purely nutritional support. Data obtained from Syria, Bangladesh and Ghana and indicated that dietary lysine provided benefits that were no fully linked to nutrition. It reduced morbidity caused by diarrhea and improved mental health of the tested subjects. Considering that poor populations ingest diets poor in lysine from very early age, the results are shocking and call for immediate enforcement of dietary policies.

Finally, no relevant tests have been conducted in rich countries among vegetarians or elderly who avoid meat products. But, the message is clear; essential amino acid content of your diet, and especially a diet of your small kids, is very important!