Genetic deficiencies in the creatine biosynthetic pathway lead to various severe neurological defects. Clinically, there are three distinct disorders of creatine metabolism. Deficiencies in the two synthesis enzymes can cause L-arginine:glycine amidinotransferase deficiency caused by variants in GATM and guanidinoacetate methyltransferase deficiency, caused by variants in GAMT. Both biosynthetic defects are inherited in an autosomal recessive manner. A third defect, creatine transporter defect, is caused by mutations in SLC6A8 and inherited in a X-linked manner. This condition is related to the transport of creatine into the brain.
There is a genetic condition known as gyrate atrophy of the choroid and retina, which is associated with a high level of Ornithine in the blood and a relative decrease in Arginine, which causes a relative creatine deficiency due to L-arginine being required to make creatine and because high ornithine can suppress creatine synthesis (AGAT) in the glial cells of the retina. This condition can be attenuated by either reducting ornithine in the diet or by supplementing creatine, which is, in this instance, therapeutic.
Healthy sources of fat include: cold water oily fish (such as salmon, mackerel, and sardines), extra-virgin olive oil, peanuts (unsalted), avocado, pecans, almonds, hazelnuts, walnuts or flaxseed. Nuts (any sort, just make sure they are unsalted) are a great food to snack on if you're having trouble gaining weight, as they are not only high in calories, but they contain monounsaturated fats, a good source of protein, fibre and contain a number of essential minerals that are needed for health. For those not consuming any oily fish, you may want to consider taking a fish oil supplement, such as cod liver oil or flaxseeds.
A big clue is digestion. He does occasional cleanses. (“There’s no planes that week,” he said. “And no judgment at home.”) The slightest change in a muscle, just a stripe in a striation, is noticed. And while Heath does most workouts alone, he has a trainer, Hany Rambod, who is based in California. They see each other about once a month. In between, Heath sends photos and receives workout and dietary advice in return.
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