Phenylketonuria (PKU) - Aspartame

Phenylketonuria (PKU) is a rare, inherited metabolic disease that results in mental retardation and other neurological problems when treatment is not started within the first few weeks of life. When a very strict diet is begun early and well-maintained, effected children can expect normal development and a normal life span.

Elevations of blood phenylalanine are dangerous for those with PKU, and require treatment and modification. A child with a level less than 6 mg/dl does not need to be on a special diet and is not risk for mental retardation, but should avoid aspartame at all cost due to the 50% phenylalanine levels.

Scientists have been able to show that carriers had higher phenylalanine levels in their urine than non-carriers.

Aspartame Detoxifcation:

Phenylalanine Hydroxylase

The disease arises from the absence of a single enzyme (phenylalanine hydroxylase). This enzyme normally converts the essential amino acid, phenylalanine, to another amino acid, tyrosine. Failure of the conversion to take place results in a buildup of phenylalanine. Through a mechanism that is not well understood, the excess phenylalanine is toxic to the central nervous system and causes the severe problems normally associated with PKU. Not every child has the same degree of enzyme deficiency, however; some have enough enzyme activity that the diet can be quite liberal, while others must have the very strict diet. The nature of the diet for an individual child must be determined by an experienced PKU treatment program.

Phenylketonuria is carried through a "recessive" gene. The incidence of carriers in the general population is approximately one in fifty people. Although PKU affects only one out of every approximately 10,000 babies born in the US, there are several hundred babies diagnosed and put on a strict diet each year.

Phenylketonuria Diet

The diet for the most severe form of phenylketonuria eliminates all of the very high protein foods since all protein contains phenylalanine. This means that all concentrated sources of protein must be eliminated from the diet in order to limit the amount of phenylalanine. Except in rare circumstances, the diet does not allow consumption of meat, fish, poultry, milk, eggs, cheese, ice cream, legumes, nuts, or many products containing regular flour. A synthetic formula is used as a nutritional substitute for the eliminated foods.

Phenylketonuria Means NO Aspartame!

In the early days of treating PKU, clinicians believed that the PKU diet could be stopped at an early age around 6-10 years. However, it is now known that stopping the diet can result in a variety of serious problems. These include drops in IQ, learning disabilities, behavior problems such as hyperactivity and irritability, neurological problems such as tremors, eczema and other skin disorders, and personality disorders including schizophrenia, panic attacks and agoraphobia – all symptoms of aspartame. As a result of the problems that have developed in young people who have discontinued the diet, it is believed that the diet should be maintained for a lifetime.

It is also now believed that keeping blood phenylalanine levels in the range of 2-6 mg/dl is the safest, especially in infancy and early childhood. Frequent blood monitoring to achieve this goal is critical. All individuals, male or female, who have stopped the diet, would be wise to return to the diet under the supervision of a PKU treatment program.

Phenylketonuria and Aspartame

This sugar substitute, sold commercially as Equal and NutraSweet, was hailed as the savior for dieters who for decades had put up with saccharine's unpleasant after taste. There are quite a few problems with aspartame. The first is phenylketonuria (PKU). One out of 20,000 babies is born without the ability to metabolize phenylalanine, one of the two amino acids in aspartame. Toxic levels of this substance in the blood can result in mental retardation. Beyond PKU, several scientists believe that aspartame might cause altered brain function and behavior changes in consumers. And many people have reported the following side effects from aspartame:

  • Fibromyalgia Syndrome and symptoms of Fibromyalgia
  • Multiple Sclerosis symptoms
  • Dizziness
  • Headaches
  • Menstrual problems

Are You A Carrier?

Scientists have been able to show that carriers had higher phenylalanine levels in their urine than non-carriers. As far as I am aware, more than 100 different mutations have now been found with corresponding enzyme activities ranging from zero to normal. So, it’s better to be safe than sorry. Avoid aspartame’s levels of phenylalanine and protect yourself and your children’s health.

Phenylketonuria Links



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