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Plasma free amino acid contents in healthy Thai subjects
P Sirichakwal1, B Feungpean, K Tontisirin
1Institute of Nutrition, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
Insights
Plasma amino acid levels in healthy individuals aged 1-45 years reveal lower essential amino acids in toddlers. The essential amino acid to non-essential amino acid ratio remains normal across all age groups.
Area of Science:
- Biochemistry
- Human Physiology
- Nutritional Science
Background:
- Plasma amino acid concentrations are crucial indicators of metabolic health.
- Age-related variations in amino acid profiles are not fully characterized.
- Establishing reference ranges is vital for diagnosing metabolic and nutritional disorders.
Purpose of the Study:
- To determine plasma amino acid concentrations in healthy individuals across different age groups.
- To compare essential amino acid (EAA) and non-essential amino acid (NEAA) ratios across age cohorts.
- To provide reference data for clinical and research applications.
Main Methods:
- Plasma amino acid levels were measured in 136 healthy subjects.
- Subjects were stratified into four age groups: 1-3, 4-11, 12-19, and 20-45 years.
- Data were compared with existing literature from diverse populations.
Main Results:
- Younger children (1-3 years) exhibited slightly lower essential amino acid concentrations.
- The ratio of essential to non-essential amino acids (EAA:NEAA) was lower in the youngest group but within normal limits (>0.5).
- Mean plasma amino acid values were generally higher than in other studies, except for cystine.
Conclusions:
- Plasma amino acid profiles show subtle age-related differences in healthy individuals.
- The EAA:NEAA ratio is consistently normal across all studied age groups.
- These findings establish a reference range for plasma amino acids and EAA:NEAA ratios in healthy subjects.
Abstract:
This preliminary investigation determined the plasma amino acid concentrations in 136 healthy subjects. The subjects were divided into four groups according to their ages: gr 1; 1-3 years, gr 2; 4-11 years, gr 3; 12-19 years and gr 4; 20-45 years. Comparing among the groups, the results showed that in younger children (age 1-3 years) the essential amino acids were slightly lower than the other groups. A wide range for most amino acids were observed. The ratio of essential (EAA): non-essential amino acid (NEAA) in very young children (1-3 years) was lower than children, adolescents and adults. These ratios were normal (> 0.5). The data have been compared with those from several studies performed in normal healthy subjects of different age groups, races and dietary habits. The results showed that most of the mean values of individual amino acid were higher than others except cystine. The EAA:NEAA ratio of each age group was comparable with other reports. The mean values of plasma amino acids and EAA:NEAA ratio in healthy subjects were determined for diagnosis, follow-up and prognosis of malnourished condition, abnormal amino acid metabolism and as a reference for other purposes.
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