The Low-Carb Diet Controversy in Patients With Diabetes

How cool is this? Today’s Dietitian’s RD Lounge! I am so excited about this blog—a place where I can read about and solicit the opinions and insights of my fellow colleagues. In fact, I’m interested in your opinion on the controversy surrounding low-carbohydrate diets for people with diabetes.

In the August 2016 issue of Today’s Dietitian I wrote an article titled “Low-Carb Diets and Diabetes.” In the article I discuss carbohydrate recommendations over the past century—which have ranged from low to high. Before the discovery of insulin, diets for people with diabetes were low in carbohydrate and high in fat. After the discovery of insulin, carbohydrate recommendations began to increase reaching a high of 65% of total calories per day in 2004. Moreover, the American Diabetes Association’s (ADA) 2004 nutrition guidelines stated that low-carbohydrate diets with less than 130 g per day weren’t recommended. And finally, in the latest ADA nutrition guidelines for people with diabetes issued in 2013, we were told that there was no conclusive evidence of an ideal amount of carbohydrate intake for people with diabetes. Furthermore, after a review of current evidence in 2015, the Academy of Nutrition and Dietetics’ Evidence Analysis Library concurred that there’s no ideal amount of carbohydrate intake for people with diabetes, and collaborative goals should be developed with the person who has diabetes based on individualized assessment of current eating patterns, preferences, and metabolic goals.

Yet, as I browse through various diabetes LISTSERVs, Twitter feeds, and websites, conduct interviews, and review books about diabetes, it’s clear, despite the guidelines and expert advice, that low-carbohydrate diets for people with diabetes remain a source of controversy among nutrition professionals and patients. Why? Do you think it’s personal bias?

I recently conducted an online survey of people with diabetes. One of the questions I asked was “What ticks you off most about your diabetes educator or dietitian/nutritionist?” Here are a few of the responses:

• “Why has every CDE and dietitian I’ve seen attempt to cajole me into eating more carbohydrates?”
  
• “Only consult [endocrinologists]. Hate dietitians—too self righteous.”
  
• “She is a strict believer in ADA guidelines.”
  
• “They always ‘forget’ what diabetes is like in real-life situations. Never understand that each situation is always different.”
  
• “They know little that’s actually helpful. It’s harsh, but I’ve been hearing the same exact recommendations for the 18 years I’ve had [type 1 diabetes] and the recommendations are not even remotely helpful—usually too starch and fruit heavy, which would lead to huge [blood glucose] roller coasters for me.”
  

Do you think these survey respondents received individualized care?

One of the arguments against low-carbohydrate diets is that they’re unsustainable long term. However, Richard K. Bernstein, MD, a well-known proponent of low-carbohydrate diets and who has type 1 diabetes, has followed a very low-carbohydrate diet—30 g per day—for more than 40 years. He maintains normal blood glucose and lipid levels and has no diabetes-related complications. Granted, he’s one individual, and the carb count is very low, but doesn’t his case speak to sustainability? I think it also speaks to the need for individualization and monitoring outcomes. Bernstein has a large number of followers—particularly in the online community, also touting the benefits of low-carbohydrate diets.

In my article for Today’s Dietitian, I also reference a retrospective study in which individuals with type 1 diabetes were instructed to consume 70 to 90 g of carbohydrate per day for up to four years. Those with good adherence experienced a significant decrease in HbA1c, a dramatic reduction in hypoglycemic episodes, and improvement in lipid profiles. Bernstein attributes a reduction in hypoglycemia to what he calls the law of small numbers. He says it’s easier to match a small amount of carbohydrate with the appropriate amount of insulin in a way you can’t with a large amount of carbohydrate.

I think we all can agree that both the quantity and type of carbohydrate in a food influence blood glucose levels, and the total amount of carbohydrate patients eat is the primary—emphasis on primary—predictor of glycemic response. Research scientist Maggie Powers, PhD, RD, CDE, at the International Diabetes Center at Park Nicollet in Minneapolis, and president of health care and education at the ADA, says “The best guidance is to use glucose pattern management to assess the glycemic impact of a particular food plan and discuss next steps if target goals aren’t met. For some, this may be a decrease in carbohydrate, for some a redistribution of carbohydrate …”

As nutrition professionals, we must embrace both the art and science of diabetes management. It requires an open-minded approach, remembering that the best diet for our patients is the one they will follow. We shouldn’t assume it will be too difficult for the patient to follow. We must review the current evidence and provide patients with the pros and cons of low-carbohydrate diets. Then, together, decide on the approach—low-carbohydrate or otherwise—monitor the outcome, and make adjustments accordingly.

What are your thoughts?

Constance Brown-Riggs, MSEd, RD, CDE, CDN, is past national spokesperson for the Academy of Nutrition and Dietetics, specializing in African American nutrition, and author of The African American Guide to Living Well With Diabetes and Eating Soulfully and Healthfully With Diabetes.

http://rdlounge.com/2016/12/15/the-low-carb-diet-controversy-in-patients-with-diabetes/