{"id":24479,"date":"2026-07-20T14:25:43","date_gmt":"2026-07-20T12:25:43","guid":{"rendered":"https:\/\/metax.org\/lnaas-in-pku-explained-simply\/"},"modified":"2026-08-17T13:12:46","modified_gmt":"2026-08-17T11:12:46","slug":"lnaas-in-pku-explained-simply","status":"publish","type":"page","link":"https:\/\/metax.org\/en\/phenylketonuria\/lnaas-in-pku-explained-simply\/","title":{"rendered":"Understanding LNAA therapy for PKU"},"content":{"rendered":"<p><div class=\"fusion-fullwidth fullwidth-box fusion-builder-row-1 fusion-flex-container has-pattern-background has-mask-background nonhundred-percent-fullwidth non-hundred-percent-height-scrolling fusion-custom-z-index\" style=\"--awb-background-position:left center;--awb-border-sizes-top:0;--awb-border-sizes-bottom:0px;--awb-border-sizes-left:0px;--awb-border-sizes-right:0px;--awb-border-color:var(--awb-color4);--awb-border-radius-top-left:0px;--awb-border-radius-top-right:0px;--awb-border-radius-bottom-right:0px;--awb-border-radius-bottom-left:0px;--awb-z-index:6000;--awb-padding-right-small:10px;--awb-padding-left-small:10px;--awb-margin-top:40px;--awb-margin-bottom:0px;--awb-margin-top-medium:0px;--awb-margin-top-small:53px;--awb-flex-wrap:wrap;\" ><div class=\"fusion-builder-row fusion-row fusion-flex-align-items-flex-end fusion-flex-align-content-flex-end fusion-flex-justify-content-center fusion-flex-content-wrap\" style=\"max-width:1248px;margin-left: calc(-4% \/ 2 );margin-right: calc(-4% \/ 2 );\"><div class=\"fusion-layout-column fusion_builder_column fusion-builder-column-0 fusion-flex-column\" style=\"--awb-padding-top:4px;--awb-overflow:hidden;--awb-bg-color:var(--awb-color1);--awb-bg-color-hover:var(--awb-color1);--awb-bg-size:cover;--awb-box-shadow:6px 6px 9px -7px var(--awb-color8);;--awb-border-color:var(--awb-custom_color_7);--awb-border-top:1px;--awb-border-right:1px;--awb-border-bottom:1px;--awb-border-left:1px;--awb-border-style:solid;--awb-border-radius:5px 5px 5px 5px;--awb-width-large:45%;--awb-margin-top-large:0px;--awb-spacing-right-large:4.2666666666667%;--awb-margin-bottom-large:20px;--awb-spacing-left-large:4.2666666666667%;--awb-width-medium:45%;--awb-order-medium:0;--awb-spacing-right-medium:4.2666666666667%;--awb-spacing-left-medium:4.2666666666667%;--awb-width-small:100%;--awb-order-small:0;--awb-spacing-right-small:1.92%;--awb-spacing-left-small:1.92%;\"><div class=\"fusion-column-wrapper fusion-column-has-shadow fusion-flex-justify-content-flex-start fusion-content-layout-column\"><div class=\"fusion-title title fusion-title-1 fusion-sep-none fusion-title-center fusion-title-text fusion-title-size-one\" style=\"--awb-margin-top-small:10px;--awb-margin-right-small:0px;--awb-margin-bottom-small:10px;--awb-margin-left-small:0px;--awb-font-size:30px;\"><h1 class=\"fusion-title-heading title-heading-center fusion-responsive-typography-calculated\" style=\"margin:0;font-size:1em;--fontSize:30;line-height:1.2;\">LNAA Therapy for PKU<\/h1><\/div><\/div><\/div><\/div><\/div><div class=\"fusion-fullwidth fullwidth-box fusion-builder-row-2 fusion-flex-container has-pattern-background has-mask-background nonhundred-percent-fullwidth non-hundred-percent-height-scrolling\" style=\"--link_color: var(--awb-color2);--awb-border-sizes-top:0;--awb-border-sizes-left:0;--awb-border-sizes-right:0;--awb-border-color:var(--awb-custom_color_2);--awb-border-radius-top-left:0px;--awb-border-radius-top-right:0px;--awb-border-radius-bottom-right:0px;--awb-border-radius-bottom-left:0px;--awb-padding-top:15px;--awb-padding-right:70px;--awb-padding-bottom:3px;--awb-padding-left:70px;--awb-margin-top:-40px;--awb-margin-bottom:0px;--awb-background-color:var(--awb-color1);--awb-background-size:cover;--awb-flex-wrap:wrap;\" ><div class=\"fusion-builder-row fusion-row fusion-flex-align-items-center fusion-flex-content-wrap\" style=\"max-width:1248px;margin-left: calc(-4% \/ 2 );margin-right: calc(-4% \/ 2 );\"><div class=\"fusion-layout-column fusion_builder_column fusion-builder-column-1 fusion_builder_column_1_1 1_1 fusion-flex-column\" style=\"--awb-max-height:500px;--awb-bg-size:cover;--awb-width-large:100%;--awb-margin-top-large:40px;--awb-spacing-right-large:1.92%;--awb-margin-bottom-large:20px;--awb-spacing-left-large:1.92%;--awb-width-medium:100%;--awb-order-medium:0;--awb-spacing-right-medium:1.92%;--awb-spacing-left-medium:1.92%;--awb-width-small:100%;--awb-order-small:0;--awb-spacing-right-small:1.92%;--awb-spacing-left-small:1.92%;\"><div class=\"fusion-column-wrapper fusion-column-has-shadow fusion-flex-justify-content-flex-start fusion-content-layout-column\"><div class=\"fusion-image-element\" style=\"text-align:center;--awb-margin-right-small:-50px;--awb-margin-left-small:-50px;--awb-max-width:5000px;--awb-caption-title-font-family:var(--h2_typography-font-family);--awb-caption-title-font-weight:var(--h2_typography-font-weight);--awb-caption-title-font-style:var(--h2_typography-font-style);--awb-caption-title-size:var(--h2_typography-font-size);--awb-caption-title-transform:var(--h2_typography-text-transform);--awb-caption-title-line-height:var(--h2_typography-line-height);--awb-caption-title-letter-spacing:var(--h2_typography-letter-spacing);\"><span class=\" fusion-imageframe imageframe-none imageframe-1 hover-type-none\"><img loading=\"lazy\" decoding=\"async\" width=\"1797\" height=\"638\" title=\"Smiling woman consulting with female doctor about health\" src=\"https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_2011947814-scaled-e1784546018262.jpeg\" alt class=\"img-responsive wp-image-24465\" srcset=\"https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_2011947814-scaled-e1784546018262-200x71.jpeg 200w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_2011947814-scaled-e1784546018262-400x142.jpeg 400w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_2011947814-scaled-e1784546018262-600x213.jpeg 600w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_2011947814-scaled-e1784546018262-800x284.jpeg 800w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_2011947814-scaled-e1784546018262-1200x426.jpeg 1200w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_2011947814-scaled-e1784546018262.jpeg 1797w\" sizes=\"auto, (max-width: 640px) 100vw, 1200px\" \/><\/span><\/div><\/div><\/div><\/div><\/div><div class=\"fusion-fullwidth fullwidth-box fusion-builder-row-3 fusion-flex-container has-pattern-background has-mask-background nonhundred-percent-fullwidth non-hundred-percent-height-scrolling\" style=\"--link_color: var(--awb-color2);--awb-border-color:var(--awb-color1);--awb-border-radius-top-left:0px;--awb-border-radius-top-right:0px;--awb-border-radius-bottom-right:0px;--awb-border-radius-bottom-left:0px;--awb-padding-top:0px;--awb-padding-right:90px;--awb-padding-bottom:90px;--awb-padding-left:90px;--awb-padding-right-small:15px;--awb-padding-left-small:15px;--awb-margin-bottom:30px;--awb-background-color:var(--awb-color1);--awb-flex-wrap:wrap;\" ><div class=\"fusion-builder-row fusion-row fusion-flex-align-items-flex-start fusion-flex-content-wrap\" style=\"max-width:1248px;margin-left: calc(-4% \/ 2 );margin-right: calc(-4% \/ 2 );\"><div class=\"fusion-layout-column fusion_builder_column fusion-builder-column-2 fusion_builder_column_1_1 1_1 fusion-flex-column\" style=\"--awb-bg-color:var(--awb-color1);--awb-bg-color-hover:var(--awb-color1);--awb-bg-size:cover;--awb-width-large:100%;--awb-margin-top-large:0px;--awb-spacing-right-large:1.92%;--awb-margin-bottom-large:20px;--awb-spacing-left-large:1.92%;--awb-width-medium:100%;--awb-order-medium:0;--awb-spacing-right-medium:1.92%;--awb-spacing-left-medium:1.92%;--awb-width-small:100%;--awb-order-small:0;--awb-spacing-right-small:1.92%;--awb-spacing-left-small:1.92%;\"><div class=\"fusion-column-wrapper fusion-column-has-shadow fusion-flex-justify-content-flex-start fusion-content-layout-column\"><div class=\"fusion-text fusion-text-1\" style=\"--awb-content-alignment:justify;\"><h3 class=\"\" style=\"--fontsize: 24; line-height: 1.25; --minfontsize: 24;\" data-fontsize=\"24\" data-lineheight=\"30px\">Explained Simply \u2013 Effects, Benefits and Uses at a Glance<\/h3>\n<p>Large Neutral Amino Acids (LNAAs) are a group of large neutral amino acids that occur naturally in our bodies and perform important functions. They are components of proteins and play a role in various metabolic processes. Examples of LNAAs include tryptophan, tyrosine, leucine, isoleucine, valine, and phenylalanine.<sup>1<\/sup><\/p>\n<p>A natural diet includes the intake of LNAAs. Even people with PKU obtain these, with the exception of phenylalanine, through their amino acid mixture. In LNAA therapy, these amino acids are administered in higher amounts.<sup>2<\/sup><\/p>\n<\/div><div class=\"accordian fusion-accordian\" style=\"margin-top:20px;margin-bottom:10px;--awb-margin-top:20px;--awb-margin-bottom:10px;--awb-border-size:1px;--awb-icon-size:16px;--awb-content-font-size:var(--awb-typography4-font-size);--awb-icon-alignment:right;--awb-hover-color:var(--awb-color2);--awb-border-color:var(--awb-color3);--awb-background-color:var(--awb-color1);--awb-divider-color:var(--awb-color3);--awb-divider-hover-color:var(--awb-color3);--awb-icon-color:var(--awb-color1);--awb-title-color:var(--awb-color2);--awb-content-color:var(--awb-custom_color_3);--awb-icon-box-color:var(--awb-color2);--awb-toggle-hover-accent-color:var(--awb-color3);--awb-title-font-family:var(--awb-typography1-font-family);--awb-title-font-weight:var(--awb-typography1-font-weight);--awb-title-font-style:var(--awb-typography1-font-style);--awb-title-font-size:24px;--awb-content-font-family:var(--awb-typography4-font-family);--awb-content-font-weight:var(--awb-typography4-font-weight);--awb-content-font-style:var(--awb-typography4-font-style);\"><div class=\"panel-group fusion-toggle-icon-right fusion-toggle-icon-boxed\" id=\"accordion-24479-1\"><div class=\"fusion-panel panel-default panel-7bee8a6c61806729f fusion-toggle-has-divider\" style=\"--awb-title-font-size:20px;--awb-title-color:var(--awb-color2);--awb-content-color:var(--awb-custom_color_3);\"><div class=\"panel-heading\"><h4 class=\"panel-title toggle\" id=\"toggle_7bee8a6c61806729f\"><a aria-expanded=\"false\" aria-controls=\"7bee8a6c61806729f\" role=\"button\" data-toggle=\"collapse\" data-parent=\"#accordion-24479-1\" data-target=\"#7bee8a6c61806729f\" href=\"#7bee8a6c61806729f\"><span class=\"fusion-toggle-icon-wrapper\" aria-hidden=\"true\"><i class=\"fa-fusion-box active-icon fa-arrow-alt-circle-up fas\" aria-hidden=\"true\"><\/i><i class=\"fa-fusion-box inactive-icon fa-arrow-alt-circle-down fas\" aria-hidden=\"true\"><\/i><\/span><span class=\"fusion-toggle-heading\">How do LNAAs work in PKU?<\/span><\/a><\/h4><\/div><div id=\"7bee8a6c61806729f\" class=\"panel-collapse collapse \" aria-labelledby=\"toggle_7bee8a6c61806729f\"><div class=\"panel-body toggle-content fusion-clearfix\">\n<p>In people with PKU, the enzyme phenylalanine hydroxylase (PAH) does not function properly. As a result, the amino acid phenylalanine can not be broken down properly, causing it to accumulate in the blood. Some of the excess phenylalanine from the blood then enters the brain, where it can cause significant damage.<sup>1<\/sup><\/p>\n<p>To enter the brain, phenylalanine uses a specific transporter (LAT1) in the blood-brain barrier. The LNAAs also use this transport pathway. If a large amount of LNAAs is ingested, they compete with phenylalanine for the same transport. As a result, less phenylalanine enters the brain, while at the same time more of the other amino acids can be absorbed.<sup>1<\/sup><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-25062\" src=\"https:\/\/metax.org\/wp-content\/uploads\/22633_EN_SaFo_XPhe_LNAA_minis_Blut-Hirn-Schranke.jpg\" alt=\"\" width=\"600\" height=\"318\" srcset=\"https:\/\/metax.org\/wp-content\/uploads\/22633_EN_SaFo_XPhe_LNAA_minis_Blut-Hirn-Schranke-200x106.jpg 200w, https:\/\/metax.org\/wp-content\/uploads\/22633_EN_SaFo_XPhe_LNAA_minis_Blut-Hirn-Schranke-300x159.jpg 300w, https:\/\/metax.org\/wp-content\/uploads\/22633_EN_SaFo_XPhe_LNAA_minis_Blut-Hirn-Schranke-400x212.jpg 400w, https:\/\/metax.org\/wp-content\/uploads\/22633_EN_SaFo_XPhe_LNAA_minis_Blut-Hirn-Schranke-600x318.jpg 600w, https:\/\/metax.org\/wp-content\/uploads\/22633_EN_SaFo_XPhe_LNAA_minis_Blut-Hirn-Schranke-768x407.jpg 768w, https:\/\/metax.org\/wp-content\/uploads\/22633_EN_SaFo_XPhe_LNAA_minis_Blut-Hirn-Schranke-800x424.jpg 800w, https:\/\/metax.org\/wp-content\/uploads\/22633_EN_SaFo_XPhe_LNAA_minis_Blut-Hirn-Schranke-1024x543.jpg 1024w, https:\/\/metax.org\/wp-content\/uploads\/22633_EN_SaFo_XPhe_LNAA_minis_Blut-Hirn-Schranke-1200x637.jpg 1200w, https:\/\/metax.org\/wp-content\/uploads\/22633_EN_SaFo_XPhe_LNAA_minis_Blut-Hirn-Schranke-1536x815.jpg 1536w, https:\/\/metax.org\/wp-content\/uploads\/22633_EN_SaFo_XPhe_LNAA_minis_Blut-Hirn-Schranke.jpg 1559w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/p>\n<p>You can think of the transporter as a door through which only a few people can pass at a time. Both phenylalanine and the other large neutral amino acids are waiting in front of this door. They all want to get through. When there are many LNAAs in front of the door, they occupy the passageway more frequently. This makes it harder for phenylalanine to get through the door.<\/p>\n<\/div><\/div><\/div><div class=\"fusion-panel panel-default panel-c14a451485cdd84ca fusion-toggle-has-divider\" style=\"--awb-title-font-size:20px;\"><div class=\"panel-heading\"><h4 class=\"panel-title toggle\" id=\"toggle_c14a451485cdd84ca\"><a aria-expanded=\"false\" aria-controls=\"c14a451485cdd84ca\" role=\"button\" data-toggle=\"collapse\" data-parent=\"#accordion-24479-1\" data-target=\"#c14a451485cdd84ca\" href=\"#c14a451485cdd84ca\"><span class=\"fusion-toggle-icon-wrapper\" aria-hidden=\"true\"><i class=\"fa-fusion-box active-icon fa-arrow-alt-circle-up fas\" aria-hidden=\"true\"><\/i><i class=\"fa-fusion-box inactive-icon fa-arrow-alt-circle-down fas\" aria-hidden=\"true\"><\/i><\/span><span class=\"fusion-toggle-heading\">Do LNAAs lower blood phenylalanine levels? <\/span><\/a><\/h4><\/div><div id=\"c14a451485cdd84ca\" class=\"panel-collapse collapse \" aria-labelledby=\"toggle_c14a451485cdd84ca\"><div class=\"panel-body toggle-content fusion-clearfix\">\n<p>The goal of LNAA therapy is not to lower the level of phenylalanine in the blood. Instead, LNAAs primarily act where they compete with phenylalanine for transport into the brain \u2013 at the \u201cgateway\u201d to the brain. As a result, fewer phenylalanine molecules can enter the brain despite unchanged high blood levels.<sup>1<\/sup> Since lower phenylalanine levels in the brain are not easily detectable, it is difficult to verify the success of this therapy.<\/p>\n<\/div><\/div><\/div><div class=\"fusion-panel panel-default panel-ca0e42ca457d12978 fusion-toggle-has-divider\" style=\"--awb-title-font-size:20px;\"><div class=\"panel-heading\"><h4 class=\"panel-title toggle\" id=\"toggle_ca0e42ca457d12978\"><a aria-expanded=\"false\" aria-controls=\"ca0e42ca457d12978\" role=\"button\" data-toggle=\"collapse\" data-parent=\"#accordion-24479-1\" data-target=\"#ca0e42ca457d12978\" href=\"#ca0e42ca457d12978\"><span class=\"fusion-toggle-icon-wrapper\" aria-hidden=\"true\"><i class=\"fa-fusion-box active-icon fa-arrow-alt-circle-up fas\" aria-hidden=\"true\"><\/i><i class=\"fa-fusion-box inactive-icon fa-arrow-alt-circle-down fas\" aria-hidden=\"true\"><\/i><\/span><span class=\"fusion-toggle-heading\">Who are LNAAs suitable for? <\/span><\/a><\/h4><\/div><div id=\"ca0e42ca457d12978\" class=\"panel-collapse collapse \" aria-labelledby=\"toggle_ca0e42ca457d12978\"><div class=\"panel-body toggle-content fusion-clearfix\">\n<p>Because treatment success is difficult to measure, the current European PKU guidelines do not recommend the routine use of LNAAs.<sup>3<\/sup><\/p>\n<p>LNAAs are suitable for:<\/p>\n<ul>\n<li>Adults with PKU who find it difficult to follow the traditional low-phenylalanine diet long-term.<\/li>\n<li>Adults with PKU for whom other treatment options are not an option or who do not respond to them.<\/li>\n<li>Adults with PKU that was treated late or inadequately, for whom protecting the brain is a particular priority.<\/li>\n<\/ul>\n<p><strong>Important:<\/strong> LNAAs may be an alternative to the traditional PKU diet for these adult patients. The decision on whether treatment is appropriate should always be made in consultation with the treating metabolic center and the patient.<\/p>\n<p><b>LNAA therapy is not recommended for children and adolescent due to insufficient data. It\u00b4s not allowed to use it during pregnancy.<\/b><sup>3<\/sup><\/p>\n<\/div><\/div><\/div><div class=\"fusion-panel panel-default panel-d7464c11c892e5192 fusion-toggle-has-divider\" style=\"--awb-title-font-size:20px;\"><div class=\"panel-heading\"><h4 class=\"panel-title toggle\" id=\"toggle_d7464c11c892e5192\"><a aria-expanded=\"false\" aria-controls=\"d7464c11c892e5192\" role=\"button\" data-toggle=\"collapse\" data-parent=\"#accordion-24479-1\" data-target=\"#d7464c11c892e5192\" href=\"#d7464c11c892e5192\"><span class=\"fusion-toggle-icon-wrapper\" aria-hidden=\"true\"><i class=\"fa-fusion-box active-icon fa-arrow-alt-circle-up fas\" aria-hidden=\"true\"><\/i><i class=\"fa-fusion-box inactive-icon fa-arrow-alt-circle-down fas\" aria-hidden=\"true\"><\/i><\/span><span class=\"fusion-toggle-heading\">What are the benefits of taking LNAAs? <\/span><\/a><\/h4><\/div><div id=\"d7464c11c892e5192\" class=\"panel-collapse collapse \" aria-labelledby=\"toggle_d7464c11c892e5192\"><div class=\"panel-body toggle-content fusion-clearfix\">\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-24463 alignright\" src=\"https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_1113672429-scaled.jpeg\" alt=\"\" width=\"340\" height=\"194\" srcset=\"https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_1113672429-200x114.jpeg 200w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_1113672429-300x171.jpeg 300w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_1113672429-400x229.jpeg 400w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_1113672429-600x343.jpeg 600w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_1113672429-768x439.jpeg 768w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_1113672429-800x457.jpeg 800w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_1113672429-1024x585.jpeg 1024w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_1113672429-1200x686.jpeg 1200w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_1113672429-1536x878.jpeg 1536w, https:\/\/metax.org\/wp-content\/uploads\/AdobeStock_1113672429-scaled.jpeg 1797w\" sizes=\"auto, (max-width: 340px) 100vw, 340px\" \/>Taking LNAAs can be an alternative to traditional dietary management involving amino acid mixtures and a low-protein diet. They help ensure the body receives essential amino acids and inhibit the uptake of phenylalanine into the brain.<sup>1<\/sup><\/p>\n<p>Possible benefits of LNAA therapy may include:<\/p>\n<p style=\"padding-left: 40px;\"><strong>\u2192 Support for brain function:<\/strong> LNAAs provide important amino acids that are needed, among other things, for the production of neurotransmitters in the brain.<\/p>\n<p style=\"padding-left: 40px;\"><strong>\u2192 Improved concentration and attention:<\/strong> Some people with PKU report a positive change, but the effect varies from person to person.<\/p>\n<p style=\"padding-left: 40px;\"><strong>\u2192 Dietary Supplement:<\/strong> LNAAs can help provide certain amino acids that are consumed in smaller amounts on a low-phenylalanine diet.<\/p>\n<p style=\"padding-left: 40px;\"><strong>\u2192 More freedom:<\/strong> Depending on the individual treatment plan, taking LNAAs may allow for a less restrictive low-phenylalanine diet. Whether and to what extent the diet can be adjusted should be determined in consultation with the treating metabolic center.<sup>4<\/sup><\/p>\n<\/div><\/div><\/div><div class=\"fusion-panel panel-default panel-161dae9fe87bf68d5 fusion-toggle-has-divider\" style=\"--awb-title-font-size:20px;\"><div class=\"panel-heading\"><h4 class=\"panel-title toggle\" id=\"toggle_161dae9fe87bf68d5\"><a aria-expanded=\"false\" aria-controls=\"161dae9fe87bf68d5\" role=\"button\" data-toggle=\"collapse\" data-parent=\"#accordion-24479-1\" data-target=\"#161dae9fe87bf68d5\" href=\"#161dae9fe87bf68d5\"><span class=\"fusion-toggle-icon-wrapper\" aria-hidden=\"true\"><i class=\"fa-fusion-box active-icon fa-arrow-alt-circle-up fas\" aria-hidden=\"true\"><\/i><i class=\"fa-fusion-box inactive-icon fa-arrow-alt-circle-down fas\" aria-hidden=\"true\"><\/i><\/span><span class=\"fusion-toggle-heading\">The Most Important Points at a Glance<\/span><\/a><\/h4><\/div><div id=\"161dae9fe87bf68d5\" class=\"panel-collapse collapse \" aria-labelledby=\"toggle_161dae9fe87bf68d5\"><div class=\"panel-body toggle-content fusion-clearfix\">\n<ul>\n<li>LNAAs are large neutral amino acids.<\/li>\n<li>LNAAs act primarily at the blood-brain barrier: They compete with phenylalanine for transport into the brain and can thereby reduce the uptake of phenylalanine into the brain.<\/li>\n<li>LNAAs do not lower blood phenylalanine levels.<\/li>\n<li>LNAAs may be an alternative to the traditional PKU diet.<\/li>\n<li>Whether LNAA therapy is an option is determined on a case-by-case basis in consultation with the Metabolic Center.<\/li>\n<li>LNAA therapy is <strong>not recommended<\/strong> for <strong>children<\/strong> and <strong>must not be used during pregnancy<\/strong>.<\/li>\n<li>The effects of LNAAs vary: Some people benefit more than others.<\/li>\n<\/ul>\n<\/div><\/div><\/div><div class=\"fusion-panel panel-default panel-719dbf00a2b556a13 fusion-toggle-has-divider\" style=\"--awb-title-font-size:20px;\"><div class=\"panel-heading\"><h4 class=\"panel-title toggle\" id=\"toggle_719dbf00a2b556a13\"><a aria-expanded=\"false\" aria-controls=\"719dbf00a2b556a13\" role=\"button\" data-toggle=\"collapse\" data-parent=\"#accordion-24479-1\" data-target=\"#719dbf00a2b556a13\" href=\"#719dbf00a2b556a13\"><span class=\"fusion-toggle-icon-wrapper\" aria-hidden=\"true\"><i class=\"fa-fusion-box active-icon fa-arrow-alt-circle-up fas\" aria-hidden=\"true\"><\/i><i class=\"fa-fusion-box inactive-icon fa-arrow-alt-circle-down fas\" aria-hidden=\"true\"><\/i><\/span><span class=\"fusion-toggle-heading\">XPhe LNAA minis \u2014 When the PKU Diet Needs New Approaches<\/span><\/a><\/h4><\/div><div id=\"719dbf00a2b556a13\" class=\"panel-collapse collapse \" aria-labelledby=\"toggle_719dbf00a2b556a13\"><div class=\"panel-body toggle-content fusion-clearfix\">\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-23902 alignright\" src=\"https:\/\/metax.org\/wp-content\/uploads\/metax_xphe_lnaa_minis.png\" alt=\"XPhe LNAA minis with large neutral amino acids for PKU\/HPA patients aged 18 and older\" width=\"380\" height=\"239\" srcset=\"https:\/\/metax.org\/wp-content\/uploads\/metax_xphe_lnaa_minis-200x126.png 200w, https:\/\/metax.org\/wp-content\/uploads\/metax_xphe_lnaa_minis-300x189.png 300w, https:\/\/metax.org\/wp-content\/uploads\/metax_xphe_lnaa_minis-320x202.png 320w, https:\/\/metax.org\/wp-content\/uploads\/metax_xphe_lnaa_minis-400x252.png 400w, https:\/\/metax.org\/wp-content\/uploads\/metax_xphe_lnaa_minis.png 540w\" sizes=\"auto, (max-width: 380px) 100vw, 380px\" \/><a href=\"https:\/\/metax.org\/en\/phenylketonuria\/xphe-in-tablet-form\/xphe-lnaa-minis\/\">XPhe LNAA minis<\/a> are a food for special medical purposes (balanced diet) intended for dietary management of phenylketonuria (PKU) or hyperphenylalaninemia (HPA). They are enriched with a high content of large neutral amino acids (LNAAs).<\/p>\n<p>Thanks to their tablet form, <a href=\"https:\/\/metax.org\/en\/phenylketonuria\/xphe-in-tablet-form\/xphe-lnaa-minis\/\">XPhe LNAA minis<\/a> can be easily incorporated into your daily routine.<\/p>\n<p>For more information on the use and dosage of <a href=\"https:\/\/metax.org\/en\/phenylketonuria\/xphe-in-tablet-form\/xphe-lnaa-minis\/\">XPhe LNAA minis<\/a>, please see <strong><a href=\"https:\/\/metax.org\/wp-content\/uploads\/metax_de_patinfo_xphe_lnaa_minis.pdf\">here<\/a><\/strong>.<\/p>\n<\/div><\/div><\/div><div class=\"fusion-panel panel-default panel-d5694ced59937f070 fusion-toggle-has-divider\" style=\"--awb-title-font-size:20px;\"><div class=\"panel-heading\"><h4 class=\"panel-title toggle\" id=\"toggle_d5694ced59937f070\"><a aria-expanded=\"false\" aria-controls=\"d5694ced59937f070\" role=\"button\" data-toggle=\"collapse\" data-parent=\"#accordion-24479-1\" data-target=\"#d5694ced59937f070\" href=\"#d5694ced59937f070\"><span class=\"fusion-toggle-icon-wrapper\" aria-hidden=\"true\"><i class=\"fa-fusion-box active-icon fa-arrow-alt-circle-up fas\" aria-hidden=\"true\"><\/i><i class=\"fa-fusion-box inactive-icon fa-arrow-alt-circle-down fas\" aria-hidden=\"true\"><\/i><\/span><span class=\"fusion-toggle-heading\">References <\/span><\/a><\/h4><\/div><div id=\"d5694ced59937f070\" class=\"panel-collapse collapse \" aria-labelledby=\"toggle_d5694ced59937f070\"><div class=\"panel-body toggle-content fusion-clearfix\">\n<ol>\n<li>Pietz et al. (1999) Large neutral amino acids block the transport of phenylalanine into brain tissue in patients with phenylketonuria<\/li>\n<li>van Spronsen et al. (2010) Large neutral amino acids in the treatment of PKU: From Theory to Practice<\/li>\n<li>van Wegberg et al. (2025) European Guidelines on the Diagnosis and Treatment of Phenylketonuria: First Revision<\/li>\n<li>Ahring (2009) Large Neutral Amino Acids in Daily Practice<\/li>\n<\/ol>\n<\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/p>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":21,"featured_media":25069,"parent":18587,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-24479","page","type-page","status-publish","has-post-thumbnail","hentry"],"_links":{"self":[{"href":"https:\/\/metax.org\/en\/wp-json\/wp\/v2\/pages\/24479","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/metax.org\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/metax.org\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/metax.org\/en\/wp-json\/wp\/v2\/users\/21"}],"replies":[{"embeddable":true,"href":"https:\/\/metax.org\/en\/wp-json\/wp\/v2\/comments?post=24479"}],"version-history":[{"count":11,"href":"https:\/\/metax.org\/en\/wp-json\/wp\/v2\/pages\/24479\/revisions"}],"predecessor-version":[{"id":25067,"href":"https:\/\/metax.org\/en\/wp-json\/wp\/v2\/pages\/24479\/revisions\/25067"}],"up":[{"embeddable":true,"href":"https:\/\/metax.org\/en\/wp-json\/wp\/v2\/pages\/18587"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/metax.org\/en\/wp-json\/wp\/v2\/media\/25069"}],"wp:attachment":[{"href":"https:\/\/metax.org\/en\/wp-json\/wp\/v2\/media?parent=24479"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}