DWQA QuestionsCategory: QuestionsVlcadd- dietary restrictions
Sylvia Bellemans asked 5 years ago
My son has vlcadd (3yrs), is not symptomatic and is on high carb/low fat diet & MCT supplementation. 
Very long chain fatty acids start at C22 and up. Many natural oils have a chain length up to C18. What’s the rationale behind the dietary restrictions of limiting the Long chain fatty acids fr non-symptomatic vlcadd people?
In the Netherlands (Utrecht), they are loosening these dietary restrictions fr non symptomatic vlcadd people as it doesn’t prevent cardiac issues or rhabdomyolysis. 
What is your take on this? 

1 Answers
INFORM Physician answered 5 years ago
No one knows the real answer to this question. Fats aren’t toxic in FAODs in the same way other foods are toxic in some diseases (for example, protein in PKU). The fats that we eat are not metabolized directly by the body, but stored, then used when the body is fasting or needs extra energy. So the amount of long chain fat in your diet isn’t really a concern because of toxicity. Rather, if you are giving 20 % of your calories from MCT oil and don’t cut back on natural fats, the diet becomes to heavily weighted toward total fat. Since you need 10% of calories from long chain fat to meet essential fatty acid requirements, I usually tolerate up to 20% from long chain fats. The total fat (40%) is a bit higher but the MCT works a bit differently than long chain fat. Hope this helps. Dr. Vockley