We diligently check the carb counts on food packaging, and do the carb-counting guess-math in our heads any time we’ve got food in front of us on the table.
But as any PWD (person with diabetes) knows, carb counting is not a perfect science.
Just ask anyone with diabetes who’s eaten pizza or a fat-heavy meal and tried to gauge how to dose insulin correctly over an extended length of time. We try and try to count the precise amounts of carbs in food, but often just can’t find the magic number to keep our glucose levels in check.
So is carb-counting really the best method for a PWD to live by? Maybe not… Researchers are now exploring just how beneficial it really is, and what alternatives or “hybrid methods” might be used to best help PWDs match insulin to what is being eaten.
This topic emerged at the American Diabetes Association’s Scientific Sessions this past June, with several different research teams presenting data — including a team from Australia that’s leading the charge on a possible alternative way to calculate insulin doses.
“For people with diabetes, the message is that carbohydrate counting is not the gold standard standard that we thought it was,” said Professor Jennie Brand-Miller of the University of Sydney in Australia, one of the researchers studying this issue. “Perhaps it gets a bronze medal, but we are still looking for the gold standard.”
Kind of mind-blowing for those of us who’ve lived by the gospel of carb counts for so long, no?
Hello, Fat & Protein
A meta-analysis published in the late October edition of the new Lancet Diabetes & Endocrinology journal analyzed more than 300 studies on different methods of insulin-dosing for food in about 700 PWDs — 599 adults and 104 kids with type 1. The two methods were carb counting and other “general or alternative dietary advice,” which the researchers tell us basically involved general healthy eating tips and sometimes low glycemic food education. Brand-Miller was a lead doctor on the study, along with Kirstine Bell who’s a dietician and D-educator at the University of Sydney.
Overall, there wasn’t any “significant improvement” in A1C for those who counted carbs, compared to the others in this randomized study, Bell tells us. But that isn’t to say carb counting lacks any merit; it just may not be the full picture and there isn’t any research out there showing otherwise.
“For some people, they may find that carbohydrate counting may not give the complete picture when it comes to determining mealtime insulin doses,” Bell wrote to us in an email response. “There may be other factors that are also affecting how much insulin is needed to cover meals, including fat and protein. If you are having trouble managing your blood glucose levels despite accurate carbohydrate counting, we would recommend talking to your diabetes team.”
Interestingly, Bell and other researchers involved in related studies are not suggesting NOT using carb counting; rather, they say it can’t stand on its own and should be combined with other methods like factoring in fat, protein, and just overall timing of how long food stays in the system. The researchers say current education lacks because so many PWDs and families are only being taught to rely on carb counting alone.
OK, but how else can we approach dosing decisions?
A New Food Insulin Index (FII)
One option that Bell and Brand-Miller say could have potential is called the Food Insulin Index (FII), an investigational algorithm that can be used to measure how much insulin is best used for a particular food. The FII includes about 130 foods ranging from bread, apples, yogurt, chicken and beef. The index uses a formula based on 100g of food, measuring the impact over the course of 120 minutes after eating.
Brand-Miller says the index isn’t any more complicated than carb counting –it’s just another set of numbers to learn. If PWDs can be taught that a slice of bread is 15g of carb, then they can be taught that a similar slice of bread is worth 20 points on the index.
“The FII is a more logical way of estimating insulin doses, but it’s still in the early stages of development. If further studies are successful, then its practical use would be as simple as carbohydrate counting at present,” she said. “If we can develop satellite navigation and Google maps, we can develop an FII.”
The Australian researchers say they’re now conducting a 12-week pilot study comparing FII use with carb counting, and that more foods are being tested and added to the database. They’re also creating an iPhone app that could be used, and if the results of the pilot study prove successful they’ll plan for a 12-month study.
Re-Envisioning Meal Dosing
Of course, this new idea of an FII has its critics — including those who tend to agree that carb counting isn’t best used as a stand-alone option. Dr. Howard Wolpert of Joslin Diabetes Center believes that both the FII and carb counting have their faults by themselves, and can only be considered as part of a larger picture. He’s also been looking into the effectiveness of carb counting and possible alternatives, and suggests that “alternative insulin dosing algorithms for higher-fat meals” are needed.
He presented at our DiabetesMine D-Data ExChange event a few weeks ago, and the description of his short talk stated: “The shortcomings of this approach – which assumes that carbohydrate is the only dietary macronutrient that needs to be considered in mealtime insulin dose calculation – are further highlighted by our recently completed closed-loop research studies indicating that higher-fat meals require considerably more insulin coverage than lower-fat meals with identical carbohydrate content.”
“It’s hugely challenging and most people don’t get it right,” Wolpert said about carb counting. “Most people learn experientially what they need.”
Wolpert thinks a hybrid of the old exchange system and the current carb counting system is a way forward, possibly with the FII mixed in. He sees limits on the index because it’s only designed to look at the first 120 minutes past a meal, and many high-fat or protein-heavy meals last longer stay in the body longer than that.
“Anyone living with diabetes knows that food doesn’t just say in the system for such a short period,” he said.
This whole topic brings up images from my own past, when I was forced to use those rigid ADA exchange plans that limited what I could eat. That was back when I was growing up in the 80s and 90s, when looking at proteins and fats was part of my complicated meal-planning routine. Honestly, I was hugely relieved when I eventually went on an insulin pump and started using carb counting to achieve more flexibility in my diet. (I still do factor in non-carbs for setting extended boluses, as about 50% of protein grams and about 10% of fat grams turn into carbs over several hours.)
Thankfully, no one seems to be suggesting going all restrictive again, and whatever new approach may replace carb counting is still being worked out. But it’s fascinating to see that this now-established method is being second-guessed.
“I don’t favor going back to the old days when it was too restrictive, because controlling your diabetes meant losing motivation and people gave up,” Wolpert says. “But we were so limited by insulins of those days, and tech that wasn’t as mainstream as it is now. We have a better way to do this now, and a more structured or hybrid approach is needed for diabetes education.”
The idea of this new FII index is intriguing, but it doesn’t seem very practical, IMHO. Yes, fat and protein amounts are also listed on food labels, but it seems like the “algorithm” to cross-reference those with the carb amounts is going to require more D-math than most of us can handle… We’re talking about revamping an entire way of life for PWDs here, and something that big is never easy.
A penny for your thoughts, Fellow PWDs!