Type 1 Diabetes Prevention 'Better Than Cure'
A Winnipeg doctor wants to give newborns at high risk of Type 1 diabetes a vitamin to try to prevent them from developing the disease.
Dr. Shayne Taback is a pediatric endocrinologist. He and his team in other locations say it is time to rigorously test the idea that high doses of vitamin D could prevent children from getting Type 1 diabetes — children like Katrina Tobin.
The nine-year-old's daily routine includes needles before meals and blood glucose tests. Tobin was diagnosed when she was a preschooler, and since then she’s had more than 1,000 needle pricks each year. She is required to test her blood sugar levels before her insulin injections.
"Sometimes at two or three in the morning, one of us will get up and we will test her and see where her blood sugar level is," said her mother, Donna Tobin. "You always think about it."
Katrina is one of the nearly 300,000 children in Canada diagnosed with Type 1, which is on the rise in northern countries.
Researchers know that the incidence of diabetes is higher farther from the equator. One theory is that there's a direct relationship between an insufficiency of vitamin D and the onset of Type 1 diabetes.
Type 1 diabetes is considered an autoimmune disease in which the body makes little or no insulin to regulate blood sugar levels. It's different from Type 2 diabetes, which tends to affect adults and is often a complication of being overweight or obese.
Finland has one of the highest known rates of Type 1 diabetes. Taback's proposal would not be the first time investigators probe the link to vitamin D. In 2001, Finnish researchers published a study on vitamin D supplementation and Type 1 diabetes rates in a group of babies who were followed for three decades.
Vitamin D doses
"As has been suggested for adults, discussions for increasing the current allowance of vitamin D for infants and children might be indicated," Elina Hyppönen and her co-authors concluded in the medical journal The Lancet.
"Any changes in the recommendations must be made with caution. We suggest that, before any changes are made, health workers ensure that all infants are receiving at least the amount of vitamin D indicated in the current recommendations."
Taback expects to find out this month if he's allowed to go ahead with a clinical trial. He's submitted a proposal seeking $10 million in research funding over the next three years to give babies at high risk of Type 1 diabetes up to 2,000 IU a day of vitamin D as a preventive strategy.
"In many ways prevention would be much better than cure as it spares people from having to go through the disease itself," said Taback.
The idea of giving vitamin D to prevent the autoimmune disorder arose after scientists found that both the immune system and the insulin-secreting beta cells in the diabetic pancreas have receptors for the vitamin, said Taback's Belgian colleague, Dr. Chantal Mathieu.
Mathieu calls vitamin D a "simple, harmless intervention" that could counter a common nutritional deficiency in northern areas of the world.
Pregnant women and newborns are already given vitamin D doses to prevent rickets and foster healthy bones. But Mathieu and Taback believe those amounts are too low to interfere with the development of diseases such as Type 1 diabetes.
"My advice is very simple for everyone with Type 1 diabetes or any other autoimmune disease in the family," Mathieu said in an interview.
"I would suggest avoiding vitamin D deficiency at a young age. At present, that means just taking the regular [amounts] that are being advised by your national guidelines."
Researchers still need to show whether giving high doses of vitamin D to babies is safe and effective, Taback cautioned.
Health Canada advises 400 IU of vitamin D for babies.
Taback and his colleagues estimate they'll need to screen up to 60,000 newborns and then enrol about 5,000 infants considered at genetic risk of developing Type 1 in the vitamin D study.
Those children will be followed to track any changes in rates of Type 1 diabetes.
Katrina's mother knows that Taback's research won't change her daughter's life. But she said knowing that it was research like his that led to the discovery of insulin makes her want to wish him every success with the test.
This week CBC News reports on the search for cures for aging, Type 1 diabetes, the common cold, obesity and cancer on CBC Radio One, CBC News Network, The National and at cbc.ca/news/health/.