Mary Bodzo’s daughter Krista is now 27. Born with spinal muscular atrophy (SMA), her condition is stable, and Bodzo attributes that to the amino acid diet that Krista began at age 5.
“We completely believe that changing her diet was what kept her stable,” Bodzo said in an interview with SMA News Today.
At the age of 8 months, Krista was diagnosed with Type 2 SMA. As she neared her fifth birthday, she was losing her ability to swallow. That’s when Bodzo, a mother of five who lives in Ocala, Florida, decided to try a nutritional approach now known as the amino acid diet.
This diet substitutes milk and soy formulas with a low-fat, elemental, free-form amino acid formula, made from nutrients in their most broken-down form that requires very little digestion.
The diet is not an exact science. Children with SMA seem to react badly to the protein and fat in dairy and soy formulas. But when the protein and fat are replaced with free-form amino acids and reduced fat, they can breathe more easily and have fewer metabolic complications, Bodzo wrote in a description of the diet posted in 2011 on the website Sophia’s Cure.
Children with Type 1, the most severe form of SMA, who begin the diet often see an immediate reduction in airway secretions, she wrote. They are less likely to be constipated, and some actually improve their strength and regain some function.
SMA is caused by a deficiency of the survival motor neuron (SMN) protein, according to the Muscular Dystrophy Association (MDA). In many cases, although not all, it results from mutations of chromosome 5 in the SMN1 gene. The primary symptoms of SMA are weakness of the muscles closest to the body’s core — the shoulders, back, hips and thighs. Muscles controlling breathing and swallowing can also be affected.
Bodzo described SMA as an inherited disease that reduces muscle mass, which prevents proper absorption and storage of amino acids and fat.
The MDA is less certain of dietary benefits, as it states on its website, Medical Management. “Many people wonder if a special diet will affect the course of SMA. … So far, there’s little evidence to suggest that any particular type of diet is useful against SMA — and in fact, some diets may be harmful.”
“For example,” the page continues, “special formulas made up of broken-down protein components called amino acids — so-called ‘elemental diets’ — actually may cause problems for children with SMA who may have little muscle tissue. Some experts say blood levels of these amino acids can become too high if there isn’t enough muscle tissue to properly use them.”
Cure SMA, which posts a document describing the diet and offered by four medical professionals, is neutral toward it. The four end their description with a “strong recommendation” that any dietary plan for a child with SMA be done under the guidance of a registered dietitian or nutritionist.
According to Bodzo, the AA diet, as it’s called, adjusts for this lack of skeletal muscle. “You don’t metabolize nutrients the same,” Bodzo said. “That’s just a basic fact of biochemistry. Overfeeding and overloading is one of the biggest issues.” Intact proteins, for reasons unknown, seem to cause problems, she said. “The more affected a child is with SMA, the more reactive they’re going to be to dairy and animal-based proteins.”
Tolerex and Pediatric Vivonex, both made by Nestle Health Science, are two common used products that form the basis for the diet. Additional ingredients might include water, almond milk, white grape juice and Pedialyte mixes with ingredients that may range from safflower oil and MiraLAX, to cornstarch and levocarnitine. Bodzo says that supplements should be determined based on “personal tolerance and nutritional lab result.”
Some children take the diet orally, others use a gastrostomy tube or G-tube. Vitamins and supplements should also be given, but fats like safflower oil, evening primrose oil or an omega-3 supplement should be added based on the individual as determined by tolerance and lab tests, she says. Some SMA patients can eat solid foods along with the amino acid diet; some parents mix breast milk into the liquid.
Bodzo said she noticed Krista reacted badly when she took her daughter off breast milk at six months of age and began feeding her dairy. “That’s when she went downhill,” she told us.
After the SMA diagnosis, she tried feeding Krista formulas based on soy, goat’s milk, and breast milk. Finally, she met another mom of an SMA patient who put her in touch with a gastrointestinal doctor who introduced Bodzo to elemental formulas, which means there’s no food source for the protein.
“I educated myself as much as a lay person can,” she said. “It’s more of a vegan-based diet.” From then on, it was trial and error to see what worked best for Krista.
All SMA patients need an individualized plan when trying the AA diet, Bodzo said. She did receive guidance from professionals while educating herself about Krista’s dietary needs, she said. The AA diet doesn’t supply complete nutrition — and that’s where nutritional guidance is needed, she said.
Parents who want to try the AA diet may have to do their own digging for information, Bodzo said. Beside the Cure SMA site, it’s also listed by Support SMA. The University of Maryland Medical Center discusses facets of the amino acid diet at its Muscular Dystrophy website, under the heading “Complementary and Alternative Therapies.”
No published studies have investigated the diet, according to Bodzo. The National Institutes of Health (NIH) reviewed the practice in a nutritional survey of 44 caregivers of SMA Type 1 children whose average age was 5, The 2014 survey, published in the Journal of Child Neurology, did find that most families were feeding their children, largely via a gastrostomy tube, an “elemental” — or amino acid-free — diet.
“Although formal studies are not available … to assess the potential benefits and risks of using such formulas, caregivers … list a number of potential benefits and observed improvements in their child with spinal muscular atrophy after switching to an elemental or semi-elemental formula,” the researchers wrote, recommending that research begin into such diets to support “better management” of SMA children.
Melissa Bowerman, a lecturer at Keele University in Staffordshire, England, is studying the use of amino acid supplements in SMA patients. Bowerman said in an email that she is investigating how nutritional support, such as the AA diet, may help these patients. Preliminary work, she added, suggests that AA supplementation may counteract components of AA processing that are hyperactivated in SMA muscles and other tissues. Bowerman’s work is being funded, in part, by SMA Angels.
Many families, however, work without the guidance of a registered dietitian, Bodzo said. Creating evidence-based nutritional guidelines would encourage more families to work with professionals to create a diet for their child, she added.
Bodzo began making the amino acid diet public because of the results she saw in Krista, who uses a wheelchair to get around. Krista’s muscle deterioration slowed after starting the AA diet, her mother says. When Bodzo began feeding her daughter the diet, Krista was having trouble swallowing. Today, she can eat by mouth.
“I’m just paying it forward,” Bodzo said. “I’m not getting paid. If it didn’t work, there are plenty of other things I could do with my time.”
She hopes the diet will be researched more fully, especially as advances in SMA are made. She even hopes that, one day, such attention to diet may no longer be necessary. Krista, she noted, begin receiving Spinraza in May, the only U.S. Food and Drug Administration-approved therapy for the disease.
“Things are changing with SMA because we have this treatment and more treatments are in the pipeline,” Bodzo said. “As treatments are given at birth, a lot of these metabolic issues may not be as critical.”
The NIH clinical trials website lists more than two dozen studies now underway into potential treatments or a better understanding of SMA.