Deakin University research suggests vitamin C screening key to diabetes complications

Eating more of one particular food could help control complications from diabetes, a comprehensive review suggests.

Deakin University has published a comprehensive review which suggests vitamin c levels might be connected to complications with diabetes.

COULD it be that an orange a day keeps the complications of diabetes at bay?

Deakin University researcher Dr Shaun Mason has published a comprehensive review of evidence that suggests if screening for vitamin C levels was a regular part of the clinical management of diabetes, it could help control complications of the condition where there is too much glucose in the blood.

Dr Mason, from the university’s Institute for Physical Activity and Nutrition, says regardless of whether a person has type 1, type 2 or gestational diabetes, their levels of vitamin C should be regularly screened the same way doctors test now for vitamin D deficiencies in a routine blood test.

He did a small study of Victorians with type 2 diabetes and found they were at high risk of vitamin C deficiency. Next, Dr Mason says, a large clinical trial is needed to “kick up a notch” the evidence.

Shaun Manson is a Deakin Uni researcher who wants to see screening of vitamin C levels become a routine part of clinical diabetes management. Picture: Rob Leeson.

“There are a lot of smaller studies that are very promising,” he says. “We have some good evidence, but we need evidence from a robust randomised clinical trial that can really answer the question on a convincing level.

“I am pushing for a national study and we have applied, unsuccessfully so far, for funding. We would need around $1 million to $2 million, but there is a lot of clinical interest.”

Dr Mason says his research indicates the reason people with diabetes, particularly type 2, have vitamin C deficiency is because they have higher body needs from oxidative stress, poorer uptake of the vitamin into cells, excessive losses via the kidneys and insufficient dietary intake.

“Oxidative stress is when our bodies produce excess chemicals that can oxidise and potentially damage cell tissue and cause DNA damage,” he says.

“People with diabetes have high levels of these oxidising chemicals so we wanted to understand if it was possible to neutralise them with antioxidants like vitamin C. It sounds like an easy solution, but at the end of the day it is not an all-encompassing solution. It is an addition to an existing armoury to help people improve outcomes.”

Health outcomes of diabetes that Dr Mason believes may be helped by improved levels of the vitamin include problems with blood sugar control, high blood pressure and complications such as foot ulcers and heart disease.

Dr Manson did a small study of Victorians with type 2 diabetes and found they were at high risk of vitamin C deficiency. Picture:Rob Leeson.

He says vitamin C is a relatively safe antioxidant that can be taken at modest oral doses without significant adverse effects.

“And despite previous concerns that vitamin C might interfere with blood sugar testing in diabetes patients, there is no convincing evidence for any interference in these tests when oral vitamin C supplements are taken at recommended doses.”

Dr Mason urged people to seek advice from their medical doctor before adding vitamin C supplements to their daily healthcare routine.

He says further research is needed to determine the optimal levels required to protect against diabetes-related risks, but says it is likely that regular use at modest doses such as a couple of fresh oranges a day or 500-1000mg through a daily over-the-counter supplement, could be safely added to diabetes therapies.

“Any citrus-rich foods including Kiwi fruit, berries, and vegetables such as broccoli, cauliflower and cabbage are foods that can be eaten in moderation as part of a well-balanced diet to reduce the risk of vitamin C deficiency,” Dr Mason said.

“These beneficial effects might relate to vitamin C supplementation correcting vitamin C deficiency as well as through the antioxidant effects of vitamin C.”