{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,18]],"date-time":"2025-11-18T01:18:24Z","timestamp":1763428704441,"version":"build-2065373602"},"reference-count":21,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2023,7,6]],"date-time":"2023-07-06T00:00:00Z","timestamp":1688601600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Society for Phenylketonuria (NSPKU)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>In phenylketonuria (PKU), a previous intervention study assessing the patients ability to tolerate fruits and vegetables containing phenylalanine 76\u2013100 mg\/100 g without limit or measurement, found that an extra 50 mg\/day phenylalanine, but not 100 mg\/day, was tolerated from these fruits and vegetables. In a further 6-month extension study, we examined the effect of the \u2018free\u2019 use of this group of fruits and vegetables on blood phenylalanine control. For 6 months, the patients ate fruits and vegetables containing phenylalanine 76\u2013100 mg\/100 g without limit or measurement. Three-day diet diaries and the patients\u2019 weights were collected monthly. Blood phenylalanine spots were collected weekly aiming for blood phenylalanine levels &lt;360 \u03bcmol\/L. Retrospective blood phenylalanine was collected 6 months pre-trial. All 16 patients (69% females) from the intervention study took part in the extension study. Most of the patients (n = 14\/16) had classical PKU with a median age of 10.5 years (range: 6\u201313). There was no statistically significant difference in the median blood phenylalanine pre-study (270, range: 50\u2013760 \u03bcmol\/L) compared to the 6-month extension study (250, range: 20\u2013750 \u03bcmol\/L) (p= 0.4867). The patients had a median of 21 and 22 bloodspots, pre- and post-trial, respectively. In the extension study, the patients had an actual mean intake of 11 g\/day (4\u201337) natural protein and 65 g\/day (60\u201380) protein equivalent from a protein substitute. The mean phenylalanine intake was 563 mg\/day (200\u20131850) with only 19 mg\/day (0\u2013146) phenylalanine from fruits and vegetables containing phenylalanine 76\u2013100 mg\/100 g. The weight z-scores remained unchanged (1.52 vs. 1.60, p = 0.4715). There was no adverse impact on blood phenylalanine control when fruits and vegetables containing phenylalanine 76\u2013100 mg\/100 g were eaten without limit or measurement. However, the fruits and vegetable portion sizes eaten were small (60 g\/week). Further longitudinal work is necessary to examine the \u2018free\u2019 use of fruits and vegetables containing phenylalanine 76\u2013100 mg\/100 g on metabolic control in patients with PKU.<\/jats:p>","DOI":"10.3390\/nu15133046","type":"journal-article","created":{"date-parts":[[2023,7,6]],"date-time":"2023-07-06T00:41:27Z","timestamp":1688604087000},"page":"3046","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Preliminary Data on Free Use of Fruits and Vegetables Containing Phenylalanine 76\u2013100 mg\/100 g of Food in 16 Children with Phenylketonuria: 6 Months Follow-Up"],"prefix":"10.3390","volume":"15","author":[{"given":"Alex","family":"Pinto","sequence":"first","affiliation":[{"name":"Birmingham Women\u2019s and Children\u2019s Hospital, Birmingham B4 6NH, UK"},{"name":"School of Health Professions, Faculty of Health, University of Plymouth, Plymouth PL4 8AA, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2579-8699","authenticated-orcid":false,"given":"Anne","family":"Daly","sequence":"additional","affiliation":[{"name":"Birmingham Women\u2019s and Children\u2019s Hospital, Birmingham B4 6NH, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4977-8345","authenticated-orcid":false,"given":"J\u00falio C\u00e9sar","family":"Rocha","sequence":"additional","affiliation":[{"name":"Nutrition and Metabolism, NOVA Medical School, Faculdade de Ci\u00eancias M\u00e9dicas, NMS, FCM, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal"},{"name":"CINTESIS@RISE, Nutrition and Metabolism, NOVA Medical School, Faculdade de Ci\u00eancias M\u00e9dicas, NMS, FCM, Universidade NOVA de Lisboa, 1169-056 Lisboa, Portugal"},{"name":"Reference Centre of Inherited Metabolic Diseases, Centro Hospitalar Universit\u00e1rio de Lisboa Central, 1169-045 Lisboa, Portugal"}]},{"given":"Catherine","family":"Ashmore","sequence":"additional","affiliation":[{"name":"Birmingham Women\u2019s and Children\u2019s Hospital, Birmingham B4 6NH, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7654-3621","authenticated-orcid":false,"given":"Sharon","family":"Evans","sequence":"additional","affiliation":[{"name":"Birmingham Women\u2019s and Children\u2019s Hospital, Birmingham B4 6NH, UK"}]},{"given":"Richard","family":"Jackson","sequence":"additional","affiliation":[{"name":"Cancer Research UK Liverpool Cancer Trials Unit, University of Liverpool, Liverpool L69 3GL, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7996-0095","authenticated-orcid":false,"given":"Mary","family":"Hickson","sequence":"additional","affiliation":[{"name":"School of Health Professions, Faculty of Health, University of Plymouth, Plymouth PL4 8AA, UK"}]},{"given":"Anita","family":"MacDonald","sequence":"additional","affiliation":[{"name":"Birmingham Women\u2019s and Children\u2019s Hospital, Birmingham B4 6NH, UK"},{"name":"School of Health Professions, Faculty of Health, University of Plymouth, Plymouth PL4 8AA, UK"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1417","DOI":"10.1016\/S0140-6736(10)60961-0","article-title":"Phenylketonuria","volume":"376","author":"Blau","year":"2010","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1186\/s13023-020-01391-y","article-title":"PKU dietary handbook to accompany PKU guidelines","volume":"15","author":"MacDonald","year":"2020","journal-title":"Orphanet J. 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