Table 1.
Results of laboratory quantification of 5-methyltetrahydrofolate (5-MTHF) in sampled food supplements and conformity with regulatory requirements.
| Sample ID | Labeled Amount of 5-MTHF per Dosage a | Analytically Determined Amount of 5-MTHF per Dosage | % Labeled Content b |
Comment c |
|---|---|---|---|---|
| NUT20/F/1 | 400 µg | 587 ± 6 µg | 147% | |
| NUT20/F/2 | 100 µg | 0 µg | 0% | Below limit of quantification. Below 80% limit. |
| NUT20/F/3 | 400 µg | 302 ± 13 µg | 76% | Below 80% limit |
| NUT20/F/4 | 400 µg | 587 ± 25 µg | 147% | |
| NUT20/F/5 | 300 µg | 290 ± 11 µg | 97% | |
| NUT20/F/6 | 400 µg | 1120 ± 35 µg | 280% | Above 150% limit. Above UL level. d |
Note: a Folate in the form of (a) calcium-l-methylfolate or (b) glucosamine salt of (6S)-5-methyltetrahydrofolic acid. b Percentage (%) of the laboratory-determined content of 5-MTHF in comparison with the content provided by manufacturer on labeling. c According to European Commission guidance document [30], an acceptable content is within the interval of 80–150% of the labeled content. d The tolerable upper level (UL) for intake of folate is 1000 µg [43].