When what you’ve been taught is wrong: a dietitian’s path to evidence based practice and deregistration.

Before my deregistration by the Dietitians Association of Australia (DAA) in April 2015, I had been a dietitian for over 35 years. It was only for the last 10-12 years of practice that restricting carbohydrate became a primary intervention for clients with type 2 diabetes and insulin resistance. In this blog, I will take you through the triggers that shifted my practice to include lower carbohydrate approaches.

 

When I graduated in 1979, much of our dietetic training was based on a set of non-referenced, unsubstantiated and untested guidelines, put out by the Australian Dietitians Association, now known as the DAA, in a little pamphlet called “Stop and Think Before You Eat and Drink”. Link to prev blog We were taught that these guidelines formed the basis of a healthy diet for everyone and as far as I remember they were not questioned openly by the nutrition community in Australia back then. And certainly we were not encouraged to do so as students .

We weren’t taught the origins of “beliefs” such as “atherosclerosis is caused by the deposition of cholesterol in arteries”, “saturated fat increases blood cholesterol levels” and that “weight gain or loss is entirely due to energy balance”. We were taught these as facts. And that is a big disadvantage when you come face to face with different facts or opposition. It’s difficult to discuss, consider and assimilate other ideas if you don’t know the strengths and weaknesses of your own.

Basically we went to work as university trained “experts”, to educate people about nutrition with a set of “beliefs” that we didn’t know the background to and could therefore not defend, nor even discuss, rationally and logically. I’m not sure that much has changed and unfortunately often see challenges to our still unsubstantiated and untested diet guidelines being met with emotion and defensive behaviour, which is the usual resort when support from facts, logic or science isn’t available.

1980: entry into the workforce 

After graduating, my first position was at a large teaching hospital in Melbourne, predominately with the diabetes unit. At that time, diet advice to people with type 2 diabetes included recommending daily ‘portions’ of carbohydrate foods; specifically, 12 portions for weight maintenance and 10 portions for weight loss. At that time, one portion was equivalent to 10 gm carbohydrate, which translated into diets containing 100 to 120 gm carbs a day.

Then, in the early 80s, with the flick of a pen, one portion suddenly became 15 gm of carbs and overnight people with type 2 diabetes were advised to up their carb intake by 50%. The main reason for this change appears to be for continuity between Australian States and Territories. It was also considered easier for Australians to translate one portion of carbohydrate into food serves, as 15 gm was closer to the amount of carbohydrate in a regular slice of bread.

Also at this time, the only way patients could monitor their blood glucose was in a clinical setting. Blood-glucose machines had become available in hospitals but being big, expensive, and taking 2 minutes to get one reading, regular monitoring of blood glucose at home was impractical. This left measuring the amount of glucose that had spilled into the urine as the main monitoring practice, and of course was so imprecise that, unlike now, no connection between diet and BGLs could be accurately made.

Break from dietetics

After 3 years of advising patients on the “recommended dietary advice” of that time, as I’d been taught, I took a break from dietetics to start a family. We moved to the country for what we considered a good lifestyle for children; home grown/ home cooked vegetarian meals, little processed foods, plenty of outside play and TV time limited to what my now adult children refer to as “deprivation levels”.

Two of my children thrived in this environment—healthy, energetic and lean—but my middle daughter, Jeanne, was different. She gained weight around the tummy at an early age, seemed to have less energy than her siblings, was a mouth-breather, suffered with reflux and could be moody at times: all signs I now recognise as relating to insulin resistance.

At around 12 years of age she gained a lot of weight quite quickly and by age 14 was borderline obese. And I was at loss to explain why.

I am forever grateful that I was in the right place at the right time to meet a GP whose family situation was remarkably similar to mine; 3 slim, high energy, eat-what-they-like children and one with a weight problem. After hearing about the presence of insulin resistance in young, seemingly healthy children, and not just in people with diabetes as she had been taught, this GP had her daughter tested and suggested the same for Jeanne, who was 14 years old at this time.

A two-hour Glucose Tolerance Test with the addition of 5 insulin measures showed normal blood glucose levels but a high insulin response, fitting the diagnostic criteria for insulin resistance.

My knowledge about insulin resistance was limited to “a connection with type 2 diabetes” but my daughter was not diabetic. How insulin resistance fitted as a diagnosis for a 14 year old with normal blood glucose levels was a mystery to me.

Real learning begins (finally)

A Google search for insulin resistance today brings up over 49 million entries. My first search nearly 20 years ago brought up just over 1 million entries, still enough to elicit the question: “Why hadn’t I been taught any of this?” My nutritional biochemistry lectures had focused primarily on kwashiorkor and marasmus; the aetiology of insulin resistance would have been a useful addition.

And it should have been part of the curriculum because insulin resistance is not a recent discovery. Professor Gerald Reaven and others were investigating carbohydrate intolerance and insulin resistance in the 1960s. Reaven established the importance of insulin resistance in human disease, not only in type 2 diabetes but also in nondiabetic individuals, making the connection between the role of insulin resistance/compensatory hyperinsulinemia and a range of symptoms.

Once I’d narrowed down my search a little and started reading, I found answers to all the pieces of the puzzle and explanations for many of Jeanne’s symptoms: her mouth breathing and snoring; why the weight went on predominantly around her tummy; why she seemed not to have an off-switch when it came to eating at times; her mood swings, reflux and lack of energy.

If the aetiology of insulin resistance had been part of the dietetic curriculum instead of teaching the Australian Dietary Guidelines, I would have been able to offer appropriate advice to clients with type 2 diabetes and known how to improve my daughter’s health at least a decade earlier than was the case.

Carbohydrates and insulin insulin resistance 

After researching insulin resistance and Jeanne’s symptoms, it became clear that higher than normal insulin levels were to blame and that a diet designed to reduce these levels is what was needed. It was also clear that a reduced carbohydrate diet was the way to go. We started experimenting with different diet approaches, and with instant feedback available from what I jokingly called my ‘live-in guinea pig’, I learnt more than would ever be possible from just the literature or in a clinical setting. This experience was invaluable.

The diet we settled on was very low carb during the day, but allowing some carbs in the evening meal. For Jeanne, the eating plan was generally eggs, bacon, tomato, avocado for breakfast; protein and salad at lunch; protein and low carb veggies for the evening meal with some carbohydrate in the form of a small amount of fruit, plain yoghurt or dark chocolate.

This worked well; no excessive hunger, good energy levels, even moods, no reflux and easily maintained healthy weight. Jeanne has now been eating this way for many years and has maintained all those positive changes. She doesn’t think of herself as being ‘on a diet’, because as she says, “This is just the way I eat”.

Advising clients on lower carbohydrate diets

Before I started advising clients on a lower carb approach for insulin resistance and type 2 diabetes, I anticipated the ‘fat’ problem. One of the main arguments against low carb diets is that such diets are higher in fat, particularly saturated fat, which is believed to increase cholesterol levels and lead to heart disease.

Although this is not borne out in multiple clinical trials, where an improvement in lipid profiles is generally observed on low carb diets, observations from the Framingham Heart Study, a long-term and influential research project developed to identify risk factors of cardiovascular disease,should have squashed the misconconception that saturated fat and dietary cholesterol raise serum cholesterol levels before it ever took hold.

Study director Dr. William P. Castelli reported, that “……in Framingham, Mass, the more saturated fat one ate, the more cholesterol one ate, the more calories one ate, the lower the person’s serum cholesterol.” Arch Intern Med. 1992;152(7):1371-1372.

Even with this evidence, I recognised that I didn’t yet know enough to support a case for a higher fat lower carb diet if I had to “argue my case in court” (my benchmark).

To be fully confident in recommending my new lower carb diet approach to clients, I started researching what I, and I believe no dietitians who have qualified since, have been taught; the basis for the diet/heart hypothesis.

The end result of my investigation was the publication of my paper: Flaws, Fallacies and Facts: Reviewing the Early History of the Lipid and Diet/Heart Hypotheses, published in 2014 in the journal of Food and Nutrition Science.

http://www.scirp.org/journal/Home.aspx?IssueID=5519#50455

and confidence that the diet/heart hypothesis is so flawed that it should never have been used as the basis of diet recommendations.

I cautiously introduced the idea of my new approach to GPs in my area in around 2005. I explained in writing, personal discussions and presentations my plan to advise carbohydrate restriction to people who fit the diagnostic criteria of Metabolic Syndrome and were therefore likely to be insulin resistant (high triglycerides, elevated BGLs, central weight, low HDL and high BP); asked that recent biochemistry be provided and rechecked after 3 months to assess effects of the diet; that medications, especially blood pressure and blood glucose lowering medications, be monitored and reduced if required. 

Many GPs supported this new approach, some tentatively at first, and then with more enthusiasm as a result of the positive feedback from clients and the excellent results (weight loss, improved BGLs and reduction in medications) that were seen.

A stand out example of the benefits of carb reduction was reported in one of our patients – a male with type 2 diabetes. After 7 weeks on a lower carb diet he had stopped taking insulin, lost 13 kg and reduced his HbA1c from 10.7 to 7.7 mmol/l. My medical colleagues found this remarkable! As did I.

Charged with Using a “Non-Evidence-Based” Dietary Approach

For over 10 years, GPs referred patients to me because of the diet approach I used and the results they saw in their patients.

In July 2014 a dietitian initiated “an inquiry” into my use of low carb diets in the management of diabetes with my workplace and informed the DAA office of this. The complaint was regarding what the dietitian considered “..the use of non-evidence based Medical Nutrition Therapy”, specifically, the recommendation of “…….very low carbohydrate diets for the treatment of metabolic syndrome, pre-diabetes and obesity.”

In September 2014 the DAA wrote that they were “in receipt” of a complaint, with a specific area of concern being that my “recommendation of a very low carbohydrate diet for type 2 diabetes management was inconsistent with Evidence Based Practice”.

I was confident that the verdict from these investigations would be in my favour, not only because of the positive results clients were achieving, the substantial body of evidence from clinical trials supporting low carb approaches but also because I WAS following the latest guidelines from the American Diabetes Association, as was the DAA recommended practice for dietitians in Australia at that time.

How naïve to think that evidence was all that was required!

Next instalment: Evidence based Nutrition Therapy: who decides?